Strategic Management and Strategic Competitiveness Essay - 2

Strategic Management and Strategic Competitiveness - Essay Example Here it has to be mentioned that the organization chosen happens to be Wal-Mart. Wal-Mart is a publicly traded company since 1971 and the largest retailer in the country of U.S. Effect of Globalization and Technology Wal-Mart was founded by Sam Fulton in the year 1950 and in the year 1971 the company was listed as a publicly traded company. By 1990 the company had exhibited phenomenal success in the domestic market as it became the largest retailer in the nation. Wal-Mart went global for the first time in the year 1994 when the company decided to enter Canada and since then there has been no turning back. Today Wal-Mart has total of nine thousand and seven hundred units. Out of this more than five thousand units are international units. Globalization presented Wal-Mart the challenge of entering into new countries like China and Brazil having diverse cross cultural differences. But it also presented the opportunity to generate a lot more revenue and reach economies of scale. From the performance of the company it can be easily seen that the company has nullified the risks and utilized the opportunities to the fullest extent. The statistics speak for themselves. Today Wal-Mart is the largest retailer in the world. Globalization has helped the company to enter emerging markets like China, Brazil, etc. and take control of the untapped market. In short globalization has been one of the key reasons for the phenomenal success of the company (Wenderoth, 2009). Position Retailer Name 1 Wal-Mart 2 Carrefour 3 Tesco 4 Metro 5 Kroger Source: Deloitte Touche Tohmatsu Limited and STORES Media Another major change in the modus operand of the company has been the embracement of technology. It is quite needless to say that with the rise in the usage of energy round the globe, the world is likely to go through the phase of power shortage. Therefore, a lot of companies are looking to use renewable energy resources. This is also potential branding activity. Wal-Mart has been a pio neer in the usage of the modern day technology to take advantage of the use of renewable energy resources. Wal-Mart uses HVACS to reflect sunlight that reduces heat to cool the buildings. Another major change has been use of the internet. Due to rise of the use of internet, it has also become a potential marketing and sales channel. Wal-Mart has been able to develop strong digital presence both in terms of the website and social media platform. The company also provides opportunity for the customers to buy products online. Industrial organization and Resource Based model for Wal-Mart Industrial organization Model The industrial organization adds to the competitive model real life frictions such as the limited information, transaction cost and barrier to entry. Wal-Mart has been able to achieve economies of scale through the everyday low price model which has in turn acted as the potential barriers to entry. Also the globalization has helped the company a lot in becoming a market lea der. The Wal-Mart stores are also geared towards the low income customer groups (Henry, 2008). Resource Based model The resource based model of the company can be analyzed through the resource capability analysis using the VRINE model. The company has decided to focus on some capabilities such as international acquisitions, store design, supply chain and the introduction of analytics to create value for the customers. The

Contracts Coursework Example | Topics and Well Written Essays - 3000 words

Contracts - Coursework Example The consultant’s documents were submitted on time, planning permissions gained and quotes received from various contractors. The project was awarded under NEC3-ECC conditions of contract. The Project duration was agreed to be 26 months and payment to the contractor through interim valuations. The project was delayed due to late payment, lack of workmen on site, work behind schedule and late project administrator’s instructions. The contention between the parties was about payment, contractual standing of contractor’s program and principle guiding claim and dispute resolution. The project ran into great difficulties after the 10th month, accusation were exchanged, agreed payments not made and the workmen were pulled off site by the contractor which led to dispute. Table of Contents Executive Summary 1 Table of Contents 2 Introduction 3 General Principle of Construction contracts 4 Dispute resolution guidelines 5 Comparable Analysis of NEC3-ECC, JCTO5 SBC/Q 6 NEC3- ECC 8 JCTO5 SBC/Q 9 Clear Difference 10 Recommended Approach 11 References/Bibliography 14 Introduction AOS Development is a national housing development company in Edinburgh and has embarked on eighty housing units developments in Skye, Scotland. The consultant’s documents were submitted on time, planning permissions gained and quotes received from various contractors. ... The project ran into great difficulties after the 10th month, accusation were exchanged, agreed payments not made and the workmen were pulled off site by the contractor which led to dispute. It should be noted that the case did not specify the order in which the causes of delay accrued on the project site. Given the facts of the case each item will be taken in seriatim or in the order by which it was stated in the case. To illustrate: The case stipulated that the delay â€Å"was due to late payment, lack of workmen on site, work behind schedule and late project administrator’s instructions†. For purposes of this paper, it would be assumed that the delay in payment was the sole and primary reason for the lack of workmen on the site, since the amount that was due which would ideally be used to compensate the workers were not credited to the account of the contractor. This would leave the contractor no choice but to let go of the workers to prevent further losses in his co mpany. As a result of the delays in payment, which in turn resulted in the lack of workmen on the site, work will definitely be behind schedule. General Principle of Construction contracts Construction contracts define the relationship of all the parties concerned with the sole purpose and aim of completing the project on time or sooner while following the specification with fealty. In fine contracts not only define the relationship of all the parties concerned but contract also define the parameters of the obligation of each parties. As predicated contracts defines the relationship and the obligation of each party arising from the contracts (Savage & Jones Mitchell,

Crisis And Issues Faced By Toyota Business Essay

Crisis And Issues Faced By Toyota Business Essay This group project analyses the crisis and issues faced by Toyota Motor Corporation in late 2009 due to reports citing sudden unintended acceleration because incorrect floor mat placing and faulty accelerator that saw 9 million of their vehicles recalled worldwide. With these factors, we will look at what started the crisis and how it could have been prevented and solved. We will also put in a few of our recommendations that may help the crisis from happening again. COMPANY INTRODUCTION In 1933, being a division of Toyoda Automatic Loom Works was when Toyota started. The founder of Toyota was Kiichiro Toyoda, the son of Sakichi Toyoda. Under Kiichiro Toyoda, Toyota focused mostly on the production of automobiles. In his travels to Europe and the United States in 1929, Kiichiro Toyoda investigated various automobile production and begun his research on gasoline-powered engines in 1930. With the encouragement of the Japanese government, Toyodo Automatic Loom Works started to research and develop automobile production in hopes to increase sales of domestic cars. Toyota Motor Corporation was established as an independent and separate company in 1937. Toyota was committed to truck production for the Imperial Japanese Army during World War II. The trucks had a simple design such has having one headlight in the middle of the hood. Today, Toyota is the seventh largest company in the world with production facilities in 28 nations around the world. Worldwide, it is also the second largest manufacturer of automobiles. In June 2006, Toyota had 52 overseas manufacturing companies in 27 countries outside Japan. Toyota markets vehicles in more than 170 countries and regions. ORGANISATIONAL STRUCTURE The type of organizational structure adopted by Toyota Motors Corporation is divisional structure. Divisional Structure is made up of separate business units or divisions. Each of the divisions has a division manager who has authority over the unit and is responsible for performance. DESCRIPTION OF THE ORGANISATIONAL STRUCTURE Toyotas organizational structure is divided into four levels namely the Chairman, President, Executive Vice President and Senior Managing Directors Toyota Motors Corporation is headed by Fujio Cho, the Chairman of the Company. The President, Akio Toyoda, reports directly to the Chairman and has authority over the executive vice president. Each of the Executive Vice Presidents has different areas of responsibilities and has authority over their senior managing directors. These senior managing director report directly to the Executive Vice Presidents. Executive Vice President, Yukitoshi Funo is responsible for the operation in Asia, Oceania, Middle East, Africa and Latin America with the help of Senior Managing Director, Akira Okabe who is the chief officer (division manager). Executive Vice President, Atsushi Nilmi assumes responsibility over strategic production planning, production engineering and manufacturing. He oversees the operation in North America and China with the help of Akira Sasaki, Senior Managing Director, who is the chief officer (division manager) for the China operation group. Yoshimi Inaba is the Chief Officer for the North America operation group. Satoshi Ozawa will assume responsibility over Operation in Europe with the help of Senior Managing director, Yoshimasa Ishii who is the chief officer for the Europe Operation group. The organizational structure adopted by Toyota is relevant to the organization. As Toyota focus is very much on quality, dependability and value, the organizational structure of Toyota has enabled it to focus on both result and quality. The organizational structure also allows the headquarter staff to focus on long term strategic planning and improvement to product. DIAGRAM ORGANISATIONAL STRUCTURE COMPANY CULTURE One of Toyotas culture is outcome orientation. The organization has â€Å"strong beliefs in quality, dependability and value†which brings about the second culture of attention to detail. The organization depicts attention to detail by adopting â€Å"standardization of work in the manufacturing process. As the manufacturing processes are standardized, Toyota was able to focus their attention on the detail which helps to ensure quality.† 4This is in line with Toyotas culture of outcome orientation. The third culture is team orientation. â€Å"Toyota organized its workforce into teams and each team member is responsible for quality inspection, problem solving and generating ideas†4 for continuous improvement. The last culture of Toyota is innovation and risk taking. Throughout Toyotas history, the company has come out many types of motor vehicle. As the company involves itself in a certain level of risk taking, it has become one of the leading creators of motor vehicle. However, some of the Toyotas culture may be responsible for the crisis that happens in 2009. Because of standardization of work, the process of manufacturing gets repeated over and over again, making the job seem boring. This will cause the worker to lose concentration which resulted in a lapse of quality. The culture of continuous improvement may also have caused the crisis. As the company focuses on continuous improvement, they try out new ideas that have not been fully explored. For example to make a thing a certain way to improve the vehicle further, however, they fail to see that the improvement made to the vehicle might cause a problem. For this instance, the improper installation of the floor mat that result in the accelerator getting stuck and causing tragedy. In conclusion, Toyota still has a strong culture which has enable the company to become one of the most reputable companies for quality. THE CRISIS In late 2009, Toyota Motor Corporation saw 9 million of their vehicles recalled due to reports that several vehicles experienced unintended acceleration. The sudden unintended acceleration (SUA) was the main crisis that Toyota faced; causing a chain of reaction that resulted in a series of other problems. Sudden unintended acceleration (SUA) occurs when the vehicle accelerates from a stationary position without the drivers intention or control. The reasons for it happening vary from driver error to faulty car parts. However, in Toyotas case, it was assumed that due to a trapped accelerator pedal when the drivers floor mat was incorrectly placed that caused the SUA. This assumption initiated the first recall on 2 November 2009. 5.2 million vehicles were affected. It was later found that a mechanical sticking of the accelerator pedal caused the unintended acceleration. Another 2.3 million vehicles were recalled for that problem. 1.8 million vehicles were found to have both the problems and were promptly recalled as well. In February 2010, a recall was also made for the hybrid anti-lock brake software. Although this was a recall different from the initial incorrect placement of the floor mat, it affected Toyotas image and brand name worldwide. With the economic downturn in 2009, Toyota faced a further financial problem with the recalls of the faulty vehicles. This resulted in the numerous jobs lost and shares plummeting in value by 15%. On 28 August 2009, Mark Saylor, an off-duty California Highway Patrol Officer, was driving on the highway with his family when his car, a Lexus ES350 unexpectedly accelerated without control. Upon collision with another car, it descended down an embankment and caught fire. One of the passengers called 911 while the car was speeding at over 100mph, reporting that the car has â€Å"no brakes†. All four were killed in the crash. Reports from Toyota and local authorities showed that the Lexus may have the wrong floor mats installed, causing it to meddle with the gas pedal. (motortrend.com/features/†¦/index.html) Further complaints stated that other several vehicles also experienced the SUA. Reports showed that these vehicles had a defect acceleration pedal. The vehicles affected were the Prius, Prius Plug in, Sei and Lexus HS 250h. Following the reports of faulty vehicles, falling consumer confidence on the Toyota brand and the fact that Toyota was trying to recover from the economic crisis of 2009, the company faced declining sales and decided on the suspension of sales for models of the affected cars and closed down six factories. This resulted in the loss of more than 6000 jobs. PROBLEMS LEADING TO THE CRISIS It has been suggested that due to Toyotas rapid growth and need to be the top between year 2000 and 2009, was the root problem that lead to the faulty vehicles and subsequently, the recall. The rapid growth and building of 17 new production sites as well as the over reliance on technology caused Toyota to forgo quality checks for some of their cars. Managers must aware of fast technology like equipment, tools or operating method that are designed to make work more efficient. Wakatsuki, a former assembly worker related how Toyota tested the safety and quality of only 60% of the cars produced. In the past, every car went through stringent checks and testing. Toyota didnt look into customer complaints and acted too slow when safety complaints came in. There were suspicions that Toyota knew about the faulty vehicles as early as September 2009, however, they only acted on the problems in January 2010. The organization should demonstrate Social Responsible Actions. There are the Social Responsibility, Social Obligation and Social Responsiveness. Social responsibility mean if the corporation must admit the mistake if they done something wrong. Such as milk powder that was sold by China. As it added Melamine in the milk powder. ALTERNATIVESTO RESOLVE CRISIS The main crisis was faulty acceleration pedals. Toyota decided that the best way to rectify the problem was to have the faulty vehicles recalled for repairs and proper checking. However, the decision to recall was not made immediately when there were early reports about the problem. There were reports stating that Toyota knew of the problems in September 2009 although the recall was only initiated on January 2010. While we agree that the recall was a good solution, it would have been better for Toyota to tackle the faulty vehicles the moment complaints started coming in. The company should not have tried to hide the reports in order to save their branding. Rectifying the problem immediately would have definitely prevented further problems and possible accidents. It would have also restored consumer confidence knowing that Toyota was prompt in reporting a problem with the cars and had plans to fix the problem. It was good to know that Toyota suspended sales and productions of the vehicle models that were suspected to be faulty, preventing more complaints and declining consumer confidence. Toyota admitted that for the past few years, they have been expanding its business rapidly and this growth has proven to be too quick for them. They may have over looked the priority of safety, quality and volume. All these according to Toyota have made them become confused. 6 RECOMMENDATIONS Although Toyota were eager to expand their business and grow their production, its critical that they keep their quality and safety in check. To meet the growing demand of their cars, Toyota might choose to open a plant in a country that allows the company to save costs on production and manpower. However, they have to ensure that qualified and skilled technicians are recruited to affirm that the cars produced are of good quality and safe for driving. â€Å"The corporation must adopt Single-use Plan during this critical time. This is a one-time plan which specifically designed to meet the needs of a unique situation.† Toyota may rely on new technology to help with the production of the vehicles. Although it may be cost efficient, it may not always be the best choice. Over reliance on technology was what caused the faulty acceleration pedals as Toyota took for granted the safety of the cars. Technicians would have done proper testing and safety checks have been done prior to the sale of the vehicle. There might have been some oversight by the checks done by machines. Manually checking of the vehicles would ensure that nothing is out of place. As the company is steadily growing, it should not forsake the employees welfare and health. Should employees be overworked, especially those in the production line, human errors may occur that will compromise on the quality of the car. With the recalls, technicians will be kept busy with repairs on the numerous vehicles. Overworked, fatigue will set in causing occasional human errors that may have been avoidable. Managers need to ensure that employees are given the right amount of work load and clearly explain the expectations needed for the work. Managers should also arrange a discussion with the non-managerial employees for their feedback on their work load. Should the work load be too much for the technicians to handle, Toyota can look into employing workers on a contract basis. This allows the work load to be divided equally and when things are under control, the contract staff will be relieved of their duties. Toyota should have Family-Friendly Benefits that provide a wide range of scheduling that allow employees more flexibility at work and accommodation theirs needs for work and life balance. The various teams in Toyota should practice better interaction. This way, problems faced in one team can be shared and discussed to maximize on the plans to face the problems. Toyota should also make it a point not to have any secrets or hidden agenda between teams and realize that the different teams are working towards a common goal: making Toyota a successful company. Manager needs to know the Parochialism. Managers only see things through their own eyes and from their own perspective. Different countries have different values, morals, customs, political and economic systems and laws. All these can affect the managing of the business. If a team faces consumer complaints, they must be quick to address it and not hide from the upper management and other teams. This is to prevent the problem from escalating and turning it to another crisis. This is known as Social Responsibility. When the vehicle model is a success to the consumers, the company should reward the employees for the work done. The rewards can be in monetary forms or organizing activities such as sewing classes, sports activities or a short holiday trip. This not only allows employees to distress, it also enables bonding. The recognition of good work will motivate the employees to strive harder in their job to give their best for the company. This is known as Social Responsiveness. Managers of Toyota should set Goals and develop Plans. The Traditional Goals were set by top managers and flow down through the organization and become sub-goals for each organizational area. And it must be a short-term plan with a time frame of one year to solve the crisis.

The Mirrors :: English Literature Essays

The Mirrors It was a small, circular mirror. When Jake picked it up, he saw his crystal clear reflection, enhanced by the smooth, silver glass. He looked up out of the old boxes he was rummaging through to find the rest of his dimly lit garage. He could hear kids playing outside and he rubbed his hands together, trying to remedy the sting of the bitter, unrelenting cold. He picked up the mirror, and took it into his mansion of a house in a quiet, peaceful suburb. It was a Midwestern winter, and the days were short, bringing cold nights laced with the sounds of speeding cars flying down the highway. Jake heard the shrill call from his mother. "Jake, we're going to McDonald's. What do you want us to bring you back?" Jake thought about it a moment, and responded in his low, thick voice. "Im not hungry right now. Go ahead." "You really should eat!" she yelled back. He didn't respond. Instead, he went into his room, mirror in hand. Jake had long been obsessed with the paranormal, diving into books of ghosts, demons, angels, and reproductions of ancient cabalic documents. It was in these books that he learned of scrying, which is foretelling the future through the use of mirror glass. He remembered about the cool antique mirror graced with Celtic knotwork and a red runestone, and figured he would give the ancient art a shot. He opened up the book, looked at some procedures, and followed the instructions. He set out the fancy purple velour cloth on his desk and placed the circular mirror down upon it. He then eagerly looked into the book and slowly chanted the specified jargon in slow, broken Latin. With that, he blew out his candles, waiting as the book said, for the mirror's powers to unlock. Nothing happened. He got up from the chair in expectation that it wouldn't work, and proceeded to turn the lights on, when he was shocked by what he heard. It started off as a whisper barely audible, and as he listened in sheer terror it became louder and louder, till he could hear nothing else but the shrieking terror that plagued his ears. It reminded him of a dog growling as if it were intimidated, but this was much more low, and contained what could only be described as pure, clean, unadulterated evil.

Important of Tuition

Below is a free essay on â€Å"Importance Of Tuition Reimbursement† from Anti Essays, your source for free research papers, essays, and term paper examples. Importance of Tuition Reimbursement And Adult Learning Education is an important tool for individuals as well as companies. Tuition reimbursement and extra time for adult learning can benefit both an employee and an organization.Providing tuition reimbursement for employees will promote loyalty, smarter employees who will benefit the company by having employees who are more understanding of profits, inventory, and working with others, as well as create future managerial prospects to better companies as a whole. Loyal employees are a major asset to companies and play a significant role in the success, efficiency, and effectiveness that a company achieves. Loyal employees will go the extra mile to delight customers and are highly motivated in their work. These employees would also resist offers of other jobs and would recomm end their company to potential employees† (Prewitt, 2003). By promoting loyalty, employees are more likely to be on time, stay with the company at least until their education is finished and are likely to continue with the company and be promoted.The more motivation and morale employees have from taking advantage of tuition assistance, the better example they will be for other employees and the more other employees will look up to these motivated employees. Motivated employees get others motivated which can lead to higher self-esteem, which can result in higher productivity of the overall company. The more motivated employees are the more work that gets accomplished.Another benefit from companies providing tuition reimbursement for employees is to better the success of the company and to improve the overall performance of the company. â€Å"While employees are attending school, employers get the advantage of new knowledge and innovative ideas put into practice right in the wo rkplace. Employees, in turn, have the opportunity to apply their education to real business situations. And, their educational pursuits may†¦

Implications of Space and Time for Distributed Work Essay

The study conducted by Suprateek Sarker and Sundeep Sahay aims to understand the effects of differences in terms of space and time based on observations done on an information systems development (ISD) project conducted by a virtual team. To accomplish the task, the researchers and coordinators observed several US-Norwegian systems development teams and gathered communication logs from the teams observed, from which they identified both the associated problems and strategies in terms of time and space related issues involved in the function of virtual teams (Sarker and Sahay 7). In terms of space, the problems identified were difficulties in communication, connection, trust, culture adaptation, and issues related to technology (Sarker and Sahay 8, 11, 13). Of course, there were also various methods identified which were utilized by the members of the virtual teams to compensate for such problems. For one, problems in terms of communication, connection, and trust were minimized through the proper use of a chat program as well as work documentation shown by members (Sarker and Sahay 11). In terms of cultural differences, the members were able to minimize the conflicts by being culturally sensitive and building rapport (Sarker and Sahay 12). Lastly, problems based on technology related aspects such as differences in skills, language, and infrastructure were dealt with through compromises, alternative methods of representation, and positively taking diversity into context (Sarker and Sahay 14). As mentioned, not only was space taken into consideration in the study but time as well. In this sense, two general problems associated with time were identified. The first one was that differences in time zones resulted in confusion as well as varying levels of activity and productivity due to the differences in the biological clock of the members; this was addressed through time conversion methods, deciding upon a more efficient time for work, and task allocation (Sarker and Sahay 16). The second obstacle associated with time was that there were conflicts in archiving message logs. In response to these conflicts, the members utilized a common method of messaging, and some teams even used a single terminal for communication purposes (Sarker and Sahay 17). In general, the study conducted was successful in identifying several challenges and solutions utilized by virtual teams. The researchers, however, have pointed out that the members of the virtual teams in the studies were mainly students. Hence, they may not be a good representation of virtual teams in a corporate sense (Sarker and Sahay 18). Even so, given the lack of information regarding such details about the functional processes of a virtual team even with a generally praised concept (Sarker and Sahay 3), the findings derived in the study are definitely of importance especially for the further understanding of virtual teams. Work Cited Sarker, Suprateek and Sundeep Sahay. â€Å"Implications of Space and Time for Distributed Work: an Interpretative Study of US-Norwegian Systems Development Teams. † European Journal of Information Systems 13 (2004): 3–20.

Science Unit Conversion Humor

Science Unit Conversion Humor This is a list of funny, made-up scientific unit conversions. If you need help with real unit conversions, check out our collection of printable conversion worksheets and examples of worked unit conversion problems. 453.6 graham crackers 1 pound cakeExplanation: There are 453.6 grams in 1 pound.Ratio of an igloos circumference to its diameter Eskimo PiExplanation: Pi is the ratio of a circles circumference to diameter, while there is a stereotype that Eskimos dwell in igloos.2000 pounds of Chinese soup Won tonExplanation: A wonton is a type of Chinese dumpling. There are 2000 pounds in 1 ton.Time between slipping on a peel and smacking the pavement 1 bananosecondExplanation: Instead of expressing the unit in terms of nanoseconds, its bananoseconds because a banana caused the fall.1 millionth of a mouthwash 1 microscopeExplanation: This refers to the popular mouthwash, Scope. The metric prefix micro means one millionth.1 million bicycles 1 megacyclesExplanation: The metric prefix mega means 106 or one million.Weight an evangelist carries with God 1 billigramExplanation: This refers to the American evangelist Billy Graham.Time it takes to sail 220 yards at 1 nautical mile per hour Knotfurl ong 365.25 days of drinking low-calorie beer 1 Lite year16.5 feet in the Twilight Zone 1 Rod SerlingExplanation: The rod is a unit of length equal to 16.5 feet. Rod Serling is the American tv producer, screenwriter, and narrator responsible for The Twilight Zone.Basic unit of laryngitis - 1 hoarsepowerExplanation: One symptom of laryngitis is hoarseness.Shortest distance between two jokes - a straight lineExplanation: To deliver a joke as a straight line means its a short joke delivered with a straight face (like its not a joke at all).1 million microphones 1 megaphone365.25 days 1 unicycleExplanation: 365.25 days is one year or one cycle of the Earth around the Sun. Its especially clever because unicycle has another meaning. Its a bike with one wheel.Half a large intestine 1 semicolonExplanation: the large intestine is also called the colon. Since its only half a colon, its a semicolon, much like half a circle is a semicircle.2000 mockingbirds two kilomockingbirdsExplanation: To K ill a Mockingbird is a famous novel by author Harper Lee published in 1960. The kilo is the prefix for a thousand. So, 2000 is two kilo. 10 cards 1 decacardExplanation: Deca is the prefix for 10.52 cards 1 deckacardExplanation. There are 52 cards in a deck of playing cards.1,000,000 aches 1 megahurtzExplanation: There are one million (106) hertz in 1 megahertz. This is a play on words, substituting hurtz (like pain, but with a z) for hertz.1 millionth of a fish 1 microficheExplanation: The word microfiche is pronounced like micro-fish. The prefix micro means one millionth.2.4 statute miles of intravenous surgical tubing at Yale University Hospital 1 I.V. LeagueExplanation: Intravenous tubing is also called IV tubing. Yale is one of the Ivy League school, plus 2.4 statute miles is a length equal to 1 league.1 kilogram of falling figs 1 fig newtonExplanation: The newton is a unit force, which is mass under acceleration (such as youd get from falling figs). This play on words refers to the Nabisco cookie, the fig newton.1000 grams of wet socks 1 literhosenExplanation: Lederhosen are short breeches (not actually so cks). There are 1000 grams of water (more or less) in one liter. The liter is a unit of volume used for liquids, so wet socks are literhosen. 1 trillion pins 1 terrapinExplanation: The prefix terra means a trillion.10 rations 1 decarationExplanation: The prefix deca means 10.100 rations 1 C-rationExplanation: C is the Roman numeral for 100.2 monograms 1 diagramExplanation: Mono is the prefix for one, while dia means two.2 new dimes new paradigmsExplanation: Two dimes is a pair of dimes. A paradigm is a model or pattern. More Science Fun and Humor Looking for more science fun? Check out this collection of molecules with strange names, learn how to make a stink bomb, or trick your friends with disappearing ink.

A Response to Richard Vernons Article The Federal Citizen Essays

A Response to Richard Vernons Article The Federal Citizen Essays A Response to Richard Vernons Article The Federal Citizen Essay A Response to Richard Vernons Article The Federal Citizen Essay In this response I will attempt to prove that federalism is not an ideologically determined system, and that the basis of its structure is visible in all types of political orientation, such as the United States, the former Soviet Union and Canada. In this response to Richard Vernons article The Federal Citizen, I will attempt to prove that the essence of federalism is actually a general theme that is available for extraction in all levels of human interaction, from the individual in society to the highest level of supra-government. As Vernon concludes, the three conceptions which necessitate federalism as a constitutional entity are; democratic responsiveness, the openness of choice of identification, and the preservation of politics from (unqualified) nationalism.1 To begin an assessment of Vernons argument for federalism it is first necessary to have a working definition of what this system is and what the goals of its implementation are. It appears to be the idea of dual citizenship, which distinguishes the aspirations of federalism from other systems. This entails belonging to an upper-level national government as well as identifying oneself with a sub level provincial or territorial government. While this is generally agreed to be the goal of federalism, its implementation and even its purpose have been consequently stretched to all shades of the political spectre. Being a broad and loosely defined doctrine, I have chosen to divide my assessment of federalism into four sections, defined as an ideology, a political tool an individual modus operandi and as an economic model. Vernons own definition appears to fulfill the ideological perspective quite neatly and requires no further introduction. As a political tool, federalism attempts to strike a balance between the powers of governmental levels as well as providing representation for majority and minority groups simultaneously. For the individual, federalism can be viewed as a method of placing oneself in the context of ones community and nation simultaneously and separately. The economic view of the federal model is a theory for maximizing utility, in monetary and social forms, while minimizing the costs to create an optimally efficient entity. Two popular forms of federalism which can be inspected from these four perspectives are inter and intra-federalism. Inter-state federalism supports strong decentralized provincial governments where the upper level government serves to monitor the activities of the sub level governments and lead the pursuit of general common goals. From an ideological perspective, inter-state federalism avoids the problem of monarchies and empires that have a centralized structure, which makes them vulnerable to revolution or attack at a single geographical point, the Roman Empire would be a suitable example of such a system. The political analysis reveals that this breed of federalism can lead to an insulation of the individual provinces and, as in the case of Quebec, may cause individual provinces to seek secession from the federal government. It would also appear that minorities within the provinces themselves would not have as high a chance of assistance from the federal government, which would be effectively subservient to the combined powers of the provincial governments. From an individual point of view, a citizen would be more concerned with the political occurrences of her own province and feel a general apathy toward political action at the highest level as well as a disinterest in international politics. A modern example of one of the shortcomings of inter-state federalism is available in the American Civil Rights movement. A deadlock between state and federal government in Alabama meant that racial segregation policies in schools were not officially ratified until 1968, a substantially long time if one considers the date at which Abraham Lincoln officially freed African Americans. This example indicates the general problem of a lack of responsiveness by government to implement immediately the ideological principles it bases itself upon. An economic critique of inter-state federalism reveals that the lack of unification will lead to a dis-economy of scale, meaning that resources that might have been saved through mass, or national, production were used inefficiently. Another interesting consequence of the economic model analysis, is that redistribution of goods or services by a more balkanized government, has the potential of favouritism between jurisdictional levels, assuming that territorial divisions create pockets of culturally or otherwise distinct groups who may be favoured over others. As the division of power gives more individuals the authority to distribute goods or services to smaller groups of individuals, it is assumed that an increase in favouritism will occur. On the other side of the spectre we find intra-state federalism, which concentrates combined regional interests at the centre of government. While in its most extreme form intra-state federalism is nothing more than pluralism, and therefore uninteresting to an exploration of federalism; paradoxically, not all its premises have been denounced. Even anarchist writers such as Proudhon, sought the influence of the intra-state upper level government in their political writings to act as a guarantor of civil liberties and minority rights. Of course, the centralized government from this perspective does not increase its democratic responsiveness to the individual citizen, nor does it protect its citizenry from unqualified nationalism. The argument of political thinkers such as Proudhon, and later George Woodcock, is that a nation-state is too vast and remote to serve the individual citizen adequately; the bureaucracy of large government is too inhuman to accommodate the needs and desires of the people it wishes to represent. Only by narrowing the focus and reducing the size of the government and its population can the institution of government be representative of its people. This theory is considered to be a co-operative model of federalism, where all actions of government are a direct result of popular will. Unfortunately, this theory does little to support the case of minority populations and would necessitate an environment of dispassionate compromise and would pose a threat to groups that tried to distinguish themselves culturally or otherwise. This model is contrasted by a political view of pluralism, where divisions of territory are seen not as cultural demarcations but as fractions of the whole system, where power is checked and balanced by other delegates of power. This picture conflicts with the intended co-operative spirit, and would be just as likely to lead to the restraining of beneficial government action as it would be to enabling it. A division of territory will inevitably lead to inequalities between provinces, consequently, if these divisions are placed in conflict with each other there will doubtlessly be victors and vanquished. It seems fantastic that a single political system could sustain being equally present on opposite sides of the political arena. To arrive any nearer the exact nature of what federalism represents it will be necessary to look slightly more philosophically at what exactly the implications of a multi-levelled government are. Throughout the arguments presented above, it would appear that the dualistic nature of self-identification has survived. I would presently like to propose that its survival is due to the fact that it is prevalent everywhere. The attitude of being from a country but a culturally distinct part of that country is not exclusive to federal nations. I myself being from Norway, consider Bergen my home, and culturally distinct from the rest of the nation. Similar cases are extant throughout the world, from London to Thailand, people will always find ways to distinguish and associate themselves. In terms of political interests, unitary countries often have a citizenry who are more acutely aware of developments on the national level not only of their own nation but of those around it as well. The development of the European Union has had a tremendous impact on how citizens of separate nation-states see themselves as a part of a whole, and the improvement and maintenance of that whole as a collective responsibility. To expand the argument outwards, the United Nations has the potential to unify all nations as subordinate entities. It would appear that federalism is not a necessary condition for a dualistic existence where an individual feels responsibility towards two separate political bodies; the evidence seems to indicate that many people exist on multiple levels of commitment and that the numbers of these allegiances are determined by ones own awareness of the world. I would propose that the theory of Vernons dualism could be transferred to the general principle of awareness, albeit in his case of a political nature. The only remaining arguments for federalism were the three presented at the beginning of this response, namely, democratic responsiveness, choice of identification and protection from unqualified nationalism. To argue against these points individually will require that they are accepted as legitimate claims, in spite of the fact that they all contain an ideological bias. If the premise that federalism is a system without ideological attachments is accepted then all three points become moot. However, I would like to argue that another outlook is available that achieves these apparent goals of federalism. It seems that at least two of the three ideological prerequisites for the existence of federalism, the choice of identification and the protection from unqualified nationalism, can be better and more precisely met by looking outside of the national arena altogether. By having a greater awareness of ones identity in a global context, one would be more free to choose which aspects of that identity one wished to represent and less inclined towards the celebration of one nation-state alone. As argued by Plato in The Republic, the structure of man and a community serve as interchangeable vehicles. Therefore, if it is possible to define a mode of behaviour on a personal level, that exact form is applicable in a proportionate dimension to nation-states or international organisations. The argument proceeds, that an analysis of a given political structure or society will reveal the form of the individuals within that society, in effect their social roles. It is on this principle that I believe the third goal of Vernons federalism is to be found. I would like to argue that the essence of democracy is a philosophical state of being with a pattern of behaviour associated with that state. It would be futile to look to the real world for a responsive democratic government, as with federalism, democracy has become an abstract notion that all countries of the world either title themselves or aspire to. We must therefore accept democracy as an abstract mental projection, an ideal form to which we find only distortions in reality. The essence of democracy is arguably somewhere in between fairness and justice; again two abstract projections neither of which can be said to have corresponding physical manifestations. Therefore, the implications of the term democratic responsiveness are much more complex than a mere streamlining of bureaucratic protocol. I will unfortunately, be unable to give any alternative to federalism for this goal, as I am u nsure of its exact meaning and of Richard Vernons intent when he stated it. The reason that I feel Vernon and his predecessors failed to disentangle themselves from the federalist notion was that they tried to build a framework specific to their political alliances. By setting ideological parameters on a universal principle such as awareness, they blinded their own awareness to the essential truth of what they were exploring. Instead of seeing the ability to juggle several conflicting alliances simultaneously as a natural and necessary condition of human and therefore societal existence, Vernon attempted to establish an absolute truth within a very specific theoretical framework. What he failed to realize was that this basic condition of awareness was the absolute truth and that it existed independent of any political system or framework. I would like to challenge Vernon to find any extant political or social system that could not be interpreted as having his general federalist structure. In conclusion, I would argue that the importance of federalism as a dualist system is a misconception and that all politically aware people exist and view themselves in a multi-levelled society. Vernons ideological claims are not best represented by federalism from an individualistic, ideological, economic or political standpoint. The basic tenants of federalism, as outlined in his closing remarks are not representative of the broad political spectrum which the system crosses. I believe that for federalism to become a concrete political system would require a much closer definition of its constitutional framework.

A Look at James Joyce’s Display of the Challenges of Stephen as Described in His Book, A Portrait Of The Artist As A Young Man

A Look at James Joyce’s Display of the Challenges of Stephen as Described in His Book, A Portrait Of The Artist As A Young Man Children are constantly asked about their dreams and aspirations. This never-ending stream of directed questions can only lead to the disillusionment that everyone has some great destiny awaiting them. In James Joyce’s A Portrait of the Artist as a Young Man, the protagonist Stephen is struggling through inner turmoil between the man Irish society and institutions want him to be, and the man that he thinks he wants to be. This definite piece of Irish literature is so dependent upon both the politically historical and religiously centered social background that every reference is crucial to the overall feeling of the novel. However, astonishingly the overlying message surpasses the barriers of time and place to give meaning to a reader from any culture or era. Because people think there is a great destiny awaiting them, they are in constant search of a secure home to nourish their dreams and give comfort to the individual soul. The political debacle over Irish independence shined through Stephen, who although ironically was dissatisfied with his country, embodied its basic elements of individualism. Consider the Christmas dinner where Dante defended herself by stating â€Å"a priest would not be a priest if he did not tell his flock what is right and what is wrong†(31). The underlying sense of anger in this scene originates from how Mr. Casey and Mr. Dedalus are contempt with the lack of Irish independence from England. This political background is key to Stephen’s approach in his journey of becoming an artist. A parallel can be drawn to the theme of independence, and following one’s own journey rather than the road others lay out. Furthermore, as a young adult Stephen finds himself rather discontent with Ireland as his ancestors â€Å"allowed a handful of foreigners to subject them†(203). This again references Ireland’s lack of independence. Stephen eventually opts to dep art his home because Ireland’s lack of freedom was not propelling him towards his singular destiny of becoming an artist. Here Stephen was so dissatisfied with his home that out of frustration for an individually compelling environment, he leaves. These political references to emphasize independence and freedom in both the country and individual soul render late 19th century Ireland as essential to generating Joyce’s arguments. Joyce’s mockery of hypocritical religious institutions that ruled Irish society at the time emphasizes Stephen’s struggle over whether or not society was to feed his destiny or not. To begin with, society stressed upon him the indisputable influence of religion. Therefore Stephen became contrite over his sins with women. After â€Å"he had confessed and God had pardoned him, his soul was made fair and holy once more, holy and happy†(145). Stephen felt a false sense of security by the institution of religion as well as society that he was now going to be all right. Even with going though the motions of a pious Catholic, Stephen could not feel completely at home. This sheds light on how many â€Å"devout† religious beings may actually feel on the inside. Their actions are rather mechanical Not all religiously active people feel holy on the inside. Ultimately, Stephen faced the unavoidable decision to either join the priesthood or follow his â€Å"destinyâ⠂¬  to become an artist. This further ridicules the process of selecting higher religious figures. It is based on sheer outward appearance, quantity, and frequency of religious endeavors rather than the quality of religious work. Stephen realizes that Irish society is not contributing to his destiny when he comes to the consensus that â€Å"he was destined to learn his own wisdom apart from others or to learn the wisdom of others himself wandering among the snares of the world†(175). Consequently Stephen again departs his past â€Å"home† for the university that becomes his new â€Å"home† for the time being. Joyce clearly wanted to depict the oppressing and shallow nature of Irish society that revolved around religion. The Irish background adds on to the void feeling Stephen has even upon technically doing all that he was told by the institutions. Although the setting served to build the background to concepts Joyce wanted to portray, the actual ideas manifested throughout the novel are relevant to human nature regardless of generation and location. To begin with, Stephen never truly grasps the concept of â€Å"home.† As a young child he was sent to boarding school, and after returning he was constantly moving from house to house. Gradually â€Å"a vague dissatisfaction grew up within him as he looked on the quays and on the river and on the lowering skies†(66-67). From a young age Stephen grows up in a home that lacked stability. He was never able to find comfort in his own home. This dissatisfaction is universal to humans, for people find discomfort in trying to not only find their identities, but also find their destiny to where they fit in to the universe. This abstract concept is applied to Stephen as his search for identity is paralleled to truly finding his â€Å"home,† a place of security and feeli ng of belonging. It is only human nature to want to have a rightful place. Throughout the novel, Joyce masterfully takes advantage of incorporating Ireland into all aspects of the novel from its setting to character names to society. These compel the novel to be exactly that – an Irish novel. However when taking a step back, one can see that as a Bildungsroman, the theme of ones journey in search of ones destiny or place in the universe is applicable to all. Humans have an innate desire to feel at â€Å"home.† Joyce urges the reader to notice the ups and downs to hunting down what one believes is his or her destiny regardless of the rest of one’s community rather than rationally thinking through what is best for the situation.

Project of Activity Essay Example | Topics and Well Written Essays - 1000 words

Project of Activity - Essay Example S to maintain her confidentiality. Mrs. S is an elderly lady aged 60; she has undergone a total right hip replacement for neck of femur fracture. My patient is being diagnosed with seizure activity (ITU-HDU), Thyrotoxicosis, R THR, early onset dementia. She is under normal diet and fluids which she is being supervised. Mrs. S only requires minimal assistance as she can use the Zimmer to support herself as stated in the doctor’s assessment. I conducted my activity, bed bath with Mrs. S on the 29th March 2012. I did this activity in the presence of a nurse who has been monitoring Mrs. S’s health condition. The main objectives of conducting this activity, bed bath was to ensure my patient’s hygiene is maintained, ensure that the activity is documented, and ensure that my patient operates within a clean and health environment and to report any signs of possibility of deterioration of my patient’s heath. Making the patient more comfortable is imperative by ensu ring that patient centered approach is upheld. It is my responsibility to ensure that my patient stays safe from any risks which may come as a result of her condition. It is an obligation to ensure that the legal and ethical code of conduct is adhered to while conducting my activity with my patient, for example, maintaining confidentiality and respecting the views and suggestions of the patient. As part of ensuring that individual centered approach is applied, providing Mrs. S with a favorable environment makes her more comfortable and encouraged. My activity ensures that all dirt and soiled hospital dressing are dumped in a safe place; the incinerator which ensures that all is burnt without emitting gases into the atmosphere which could pollute the air, therefore, air pollution related health problems are reduced. According to the Maslow’s Hierarchy of needs, Mrs. S requires emotional, physical and psychological needs in order for her health to improve. Mrs. S has a daughter who frequently visits her to provide emotional support as well as physical support. Her daughter is very charming which while she is around; Mrs. S is seen to be very happy and seems to have forgotten anything about her illness. Sutcliffe states that it is the role of the family to ensure patients, particularly the elderly, are shown love, care and support (2011 p.36). Physically, Mrs. S is willing be supported to stand using the Zimmer frames which are readily available within the hospital although it is quite challenging. The nurses are in a position to assist Mrs. S through guidance and counseling because she is ready to listen and develop a positive attitude. Murphy, Gretebeck and Alexander (2007, p.1068) illustrate that communicating with the patient is a fundamental need while taking care of elderly patients. My ability to communicate with Mrs. S made it easy for me to know how she wanted to be handled. The fact that Mrs. S could not stand on her own needed proper communicati on when she wants support. Mrs. S, is a strong woman since she does not let her condition affect her feelings, she is very open to share with the nurses about her experiences and is very wiling to immediately report any developing pain. Documentation of any activity done with a patient is mandatory, which is part of my aim in doing the bed bath. Cooney, et al. explains that the Roper-Logan-Tierney model of nursing requires that nurses keep records of care given

Images of an "Oriental Other" Assignment

Images of an "Oriental Other" - Assignment Example But tools have changed, and nowadays Western foreign policy is expressed through mass culture and Orientalism is widely presented in mass media production (Nicha 2012). The image of â€Å"Oriental Others† discussed in this essay is the image of Persian Prince, which was presented in 2010 in American movie Prince of Persia: The Sands of Time. The part of the Prince is played by a famous American actor Jake Gyllenhaal and therefore, Persian Prince looks more like a White, Western man, a â€Å"hot†, protagonist and American superhero, as Jehanzeb Dar puts it (Dar 2010). The orientalism of the discussed image is illustrated well through a screen shot from the movie. On this picture Prince fights and defeats an antagonistic personage, a one of the hirelings Assassins, who were hired by â€Å"evil side† to kill Prince. It’s typical in modern American mass culture that the Orient got associated with mysticism, barbarism, despotism, imagination and violence, â€Å"in other words, the opposite to the world of Western Europe†, as West imagines itself (Nicha 2012). Despite that Jake Gyllenhaal visually looks more like American man than like Persian one, the whole plot of the movie and characters are presented in stereotypical way. First of all, there’s a lot of violence in a movie, a lot of fights, and on this particularly picture where Prince fights Assassin, both of them are cold steel armed with weapons traditionally associated with bloodshed. Edward Said says, it’s typical when Oriental Others are shown as people who like violence and understands only force, so â€Å"civilized people† have no other choice but to deal with them using a military force. However, the true reason such image is justification of U.S. military intervention on Middle East, and behind the p owerful myths about how Arabs’ are originally threatening for Americans, true geopolitical

Appeal admission letter to ucsd Essay Example | Topics and Well Written Essays - 500 words

Appeal admission letter to ucsd - Essay Example I play tennis in the Tennis Junior Varsity Team. I play the saxophone in the Marching Band and the violin in the Orchestra. As you will have noticed, I am not only a dedicated and responsible person in my academic work, but I am also a musician, an athlete, involved in community work, and I am environmentally versed and active. This is the reason why I am applying to UCSD. Having an Environmental Science major, a Marching Band, an Orchestra, and tennis teams will give me the opportunity to continue to excel in those areas that I am already active in and it will help me to achieve my goals and objectives by being part of your campus. I am a studious person. I start and finish tasks before or on their due dates. I work independently and as a team member. I have assumed leadership roles. I am multi-tasks disciplined and I am successful being involved in all of my tasks. I would like to be involved in assisting your faculty that is conducting research in any of these areas: global warming; shortage of power; and/or, environmental pollution. I hope that the University of California in San Diego sees in me as a successful student that will fulfill his/her (identify your gender) baccalaureate. I hope that you give me the opportunity to become part of your alumni association as my

The Matching Hypothesis Essay Example | Topics and Well Written Essays - 2000 words

The Matching Hypothesis - Essay Example The Matching Hypothesis proposes that people of similar levels of physical attractiveness gravitate toward one another (Weiten & Lloyd, 2003). For the sake of testing the validity of the Matching Hypothesis, this research study was conducted to witness whether married couples (or romantic partners) form relationships based primarily on physical attractiveness. This researcher hypothesised that there would, indeed, exist a positive correlation between couples of the same average level of physical beauty being rated on similar levels in a 1-10 scale; or that both variables representing each partner in a romantic relationship would co-vary in the same direction; thus a directional hypothesis. In a correlational research study, the correlational coefficient will vary between 0 and +1.00 (if positive) or between 0 and -1.00 (if negative). In some studies, attractiveness levels of long-term spouses have correlated above .50. (Manstead & Hewstone, 1999). Walster & Walster (1969) conducted a n experiment which indicated a .89 correlation (high) between physical attractiveness and the subsequent perceived desire for another individual. This researcher chose to analyse the results of this study using a correlational method as part of verifying the directional hypothesis. The concept of the Matching Hypothesis was offered by a professional researcher in psychology, E. Walster, who, in conjunction with various researchers, established high correlation coefficients that supported the theory. Walster and Walster (1969) conducted an experiment where participants in the study were randomly paired in a "computer dance" scenario and then issued a follow up survey to rate the acceptability of their partners. It was found in this study that physical attractiveness Further, Berscheid & Walster have conducted research studies which have supported the view that people tend to prefer partners who are more similar to them in terms of attractiveness (Harvey et al, 2004). With this

Management accounting Essay Example | Topics and Well Written Essays - 1500 words - 15

Management accounting - Essay Example On the basis of this,the budget allocation needs require to be constantly updated (Govindarajan& Shank, 1992). This report will discuss the descriptive and reflective requirement of the formal budgeting process. This has become a necessity of the business because of the increasing volatility. The budgets need to be allocated accordingly so that the benefits can be acquired. The businesses irrespective of their sizes require maintaining their budgets appropriately. With the budgeting processes,the businesses control and determine the tools through which the profits and the bonuses can be allocated within the business. The objective of budget allocation is that the companies can ensure that the financial stability is maintained and with this it also prevents the budgets from becoming negative. In the large businesses,the budgeting process has the highest priority. On the basis of this,the organizations manage their operations. The strategic managers set the goals and on the basis of finance available they allocate the budgets of accomplishing the required tasks. Once the budget is approved it becomes a road map and on the basis of this the future development is planned and structured. The budget development requires that the strategy which is approved by the strategic managers is delivered to the workforce and that they understand what the organization wants from them. The most essential use of the plan is allocation of resources and keeping the workforce prepared against the opportunities and barriers. The budgeting process can be divided into two subcategories. Theseare the traditional and zero based budgets. In the traditional budgets,the analysis is done on the basis of historical modifications and projections. All these are established on the basis of inflation and the growth rate. In the zero based budget a completely new budget is created, and all the capital is raised separately.

Appeal admission letter to ucsd Essay Example | Topics and Well Written Essays - 500 words

Appeal admission letter to ucsd - Essay Example I play tennis in the Tennis Junior Varsity Team. I play the saxophone in the Marching Band and the violin in the Orchestra. As you will have noticed, I am not only a dedicated and responsible person in my academic work, but I am also a musician, an athlete, involved in community work, and I am environmentally versed and active. This is the reason why I am applying to UCSD. Having an Environmental Science major, a Marching Band, an Orchestra, and tennis teams will give me the opportunity to continue to excel in those areas that I am already active in and it will help me to achieve my goals and objectives by being part of your campus. I am a studious person. I start and finish tasks before or on their due dates. I work independently and as a team member. I have assumed leadership roles. I am multi-tasks disciplined and I am successful being involved in all of my tasks. I would like to be involved in assisting your faculty that is conducting research in any of these areas: global warming; shortage of power; and/or, environmental pollution. I hope that the University of California in San Diego sees in me as a successful student that will fulfill his/her (identify your gender) baccalaureate. I hope that you give me the opportunity to become part of your alumni association as my

Management accounting Essay Example | Topics and Well Written Essays - 1500 words - 15

Management accounting - Essay Example On the basis of this,the budget allocation needs require to be constantly updated (Govindarajan& Shank, 1992). This report will discuss the descriptive and reflective requirement of the formal budgeting process. This has become a necessity of the business because of the increasing volatility. The budgets need to be allocated accordingly so that the benefits can be acquired. The businesses irrespective of their sizes require maintaining their budgets appropriately. With the budgeting processes,the businesses control and determine the tools through which the profits and the bonuses can be allocated within the business. The objective of budget allocation is that the companies can ensure that the financial stability is maintained and with this it also prevents the budgets from becoming negative. In the large businesses,the budgeting process has the highest priority. On the basis of this,the organizations manage their operations. The strategic managers set the goals and on the basis of finance available they allocate the budgets of accomplishing the required tasks. Once the budget is approved it becomes a road map and on the basis of this the future development is planned and structured. The budget development requires that the strategy which is approved by the strategic managers is delivered to the workforce and that they understand what the organization wants from them. The most essential use of the plan is allocation of resources and keeping the workforce prepared against the opportunities and barriers. The budgeting process can be divided into two subcategories. Theseare the traditional and zero based budgets. In the traditional budgets,the analysis is done on the basis of historical modifications and projections. All these are established on the basis of inflation and the growth rate. In the zero based budget a completely new budget is created, and all the capital is raised separately.

Reliability Issues †Centrifugal Slurry Pumps Essay Example for Free

Reliability Issues – Centrifugal Slurry Pumps Essay Introduction Pumps were probably the first machine ever developed, and are now the second most common machine in use around the world, out-numbered only by the electric motor. The very earliest type of pump is now known as a water wheel, Persian wheel or â€Å"noria†, consisting of a wheel of buckets that rotates to pick up water from a stream and dump it into a trough. Another early pump was the â€Å"Archimedean screw†, similar to the modern screw conveyor except that the flights were often fixed to the tube so that the whole arrangement would turn together. Both of these devices are still used, most commonly in basic agricultural applications. Pumps are now produced in an enormous range of types and sizes, for a very wide scope of applications, and this makes it difficult for any individual reference document or organisation to cover â€Å"pumps and pumping† as a general topic. So the broad field of pumping is classified into sub-divisions and then dealt with at that level. In the mining industry, the upper end of the pump scale includes impellers with diameters over 2.5m, slurry lines 10km long, particle size up to 100mm, flow rates handling more than 7000tph, and motors over 10MW. Finer slurries of around 1mm particle size are pumped for hundreds of kilometres in some operations. There are many ways to classify pumps. This just one of them. This document only addresses centrifugal pumps, with a focus on single-stage radial-flow slurry pumps. Centrifugal pumps are capable of meeting duties of up to 1.4 m /s at 30MPa, and higher volumes at lower 3 pressures. The maximum flow rate at low discharge pressure is about 180 m /s. Industrial applications requiring high delivery pressures generally use reciprocating fixed-displacement pumps, but they are limited in the amount of flow they can put out per unit. In general purpose applications, where different types of pumps could all deliver the performance sought, centrifugal pumps are usually the preferred choice due to lower lifecycle costs. Basic Requirements for Reliability Assuming correct pump manufacture and installation, the basic requirements for reliable long-term operation of centrifugal pumps are: 1. Continuous operation at best-efficiency point (BEP) 2. Adequate net positive suction head (NPSH) 3. Low velocity fluid flow within the pump and throughout the system 4. Processing of fluids that are benign ie: a) Chemically and physically stable b) At near-ambient temperatures c) Free of particles likely to cause wear or blockage Pumps of a basic design satisfying all these requirements have run for 50 years and more without major component replacement. The first three requirements are satisfied by matching pump performance to expected duty. Where item 4 cannot be addressed through pre-treatment of the fluid, the pump configuration, geometry and materials must be optimised to give best results. Obviously, item 4.c) is a dominating issue for slurry pumps as it cannot be eliminated and must be managed. Centrifugal Pump Construction Centrifugal pumps have two main sub-assemblies – the rotating parts (impeller, shaft, bearings), and the fixed parts (casing, piping connections, stand, foundations. Pumps of all types may be single stage or multi-stage. Multiple stages are used where it is not practical to generate the necessary discharge pressure using a single impeller. The simplest way to imagine a multi-stage pump is as one pump with its discharge feeding straight into the suction of a second pump so that the overall discharge pressure is increased while the flow rate stays the same. However, this arrangement is properly described as â€Å"single stage pumps in series†. A true multi-stage pump consists of multiple impellers mounted on a single shaft, positioned in a single casing made up of multiple chambers. Multi-stage pumps of this type are not used with slurries, but sometimes slurry pumps are mounted in series. Casing There are two types of casing designs â€Å"volute† and â€Å"diffuser†. A volute casing has a snail’s shell shape, while a diffuser casing has internal vanes. Diffuser casings are rarely used on single-stage radial pumps, and are not commonly used for handling slurries due to the flow restriction and high wear rates that would result. Slurry pumps have volute casings which house the impeller and have a spiral-shaped outer volume that extends 360 degrees and increases in cross-sectional area as it approaches the discharge flange. At full circle the volute overlaps itself, creating the cut-point, also known as â€Å"cut-water point† or â€Å"tongue†. The ideal shape is to have a steady linear increase in cross-sectional area for 360 degrees around the circumference starting from the cut-water point, but this can be difficult to manufacture. Compared to a clear water pump, a slurry pump has a much larger radial gap between cut-water point and impelle r, to reduce risk of blockage. Where a pump is identified as oversize for its duty, and is suffering high recirculation wear, it may be possible to fit liners with an extended cut-water point that throttles the flow. In theory, when a pump operates at its best efficiency point (BEP), the pressure acting on the impeller and casing are uniform. However, in practice the pressure is rarely completely uniform, and if a pump is operating away from its BEP the imbalanced in the radial forces acting on the impeller become significant. These forces are larger for bigger pumps operating at higher pressures. Running a large pump below rated capacity can create unbalanced radial forces that may (over time) damage the bearings or snap the shaft. If it is known that a pump may need to occasionally operate well away from its BEP, the manufacturer should include an oversize shaft arrangement in the design, but with commercial competition driving purchase decisions this may have to be specifically requested. Another option for reducing imbalanced radial forces is to use a twin-volute design, which consists of a wall splitting the volute in half for about half its circumference, ending after the cut-point but before the discharge flange. This is not practical for most slurry applications. Casings must be designed to allow the impeller to be installed inside, and so are manufactured in at least two parts. Solid casings have a removable cover, either on the suction side or shaft side or both, but the volute shape is a one-piece casting. Casings may also be split, either axially or radially. Axially split housings make inspection easier because the upper piece can usually be removed without disturbing the shaft or piping too much. Split casings may tend to â€Å"breathe† at high pressures, resulting in leakage, air entrainment, vibration, misalignment etc. Casings are normally provided with ribbing at the location of highest stresses, to minimise this. Open or semi-open impellers require close clearances against the casing to ensure pumping efficiency. The casings generally include a side-plate that can be adjusted for minimal clearance using jacking screws or shims, especially in wearing applications eg slurries. Impeller Impellers are classified according to their design features ie: ï‚ · Suction flow orientation o Single suction ie inlet on one side only o Double suction ie inlet on both sides ï‚ · The direction of exit flow relative to the shaft axis ie: o Radial flow o Axial flow o Mixed flow ï‚ · Vane shape ie: o Single curvature vanes, also called straight vanes – the impeller surfaces that accelerate the fluid are straight and parallel to the axis of rotation o Francis or screw vane – the surfaces that accelerate the fluid are curved in relation to the axis of rotation ï‚ · Mechanical construction o Enclosed ie with side walls or â€Å"shrouds† o Open ie no shrouds o Semi-open ie shroud on one side only o Partially shrouded ie shroud not extending to impeller tips The open area through which the fluid flows into the impeller is called the suction eye. For a closed-shroud impeller, this is simply the hole in the shroud. The suction eye area is an important featur e of the pump design. The area taken up by the shaft, if it protrudes through the eye, is deducted when calculating eye area. Impellers can be single suction or double suction. A single suction impeller has an inlet eye on one side only, with the shaft extending out the opposite side so the impeller overhangs. A double suction impeller can be thought of as two mirror-image single suction impellers mounted back-to-back. They accept fluid from both sides and usually have a shaft that extends straight through the impeller with bearings providing support on both sides. Double suction impellers are usually fed fluid from a single inlet flange, with the fluid flow being split into two streams by channelling inside the casing. Double suction units provide advantages in reduced fluid velocity at the impeller eye, and better balancing of axial hydraulic forces, while single suction units are simpler in design, manufacture and maintenance. Most if not all slurry pumps are single suction type. Some pumps may have an inducer, which is an axial flow impeller with a few blades installed between the suction inlet and the main impeller, intended to improve the suction head seen by the main impeller. Impeller shrouds often incorporate thin â€Å"pump-out vanes† cast into the outside of the shrouds. Their purpose is to help clear any solids from the back hub of the impeller (opposite the inlet eye), reduce pressure at the seal area, reduce axial thrust, and discourage recirculation. Some impellers have similar vanes on the eye side as well as the shaft side – in this case, those on the shaft side are usually called â€Å"expeller vanes†. In clear water pumps, a cylindrical ring is usually cast or machined into the outside surface of the shrouds, coinciding with a matching feature in the casing, to help seal off the discharge fluid from the suction fluid and prevent internal circulation. Clearances here are tight in order to ensure pumping efficiency – typically around 0.25mm on radius for most common sizes of industrial pumps. In larger pumps the casing (and sometimes also the impeller) is usually protected at this point by replaceable â€Å"wear rings†, which may be high-wear items, and need to be replaced before efficiencies fall too low. It is good practice to replace wear rings once the clearance reaches twice the original specification. Wear rings are provided in a wide range of designs and materials according to the pressures, speeds and fluids involved. The wear rings on impeller and casing are often made from differing materials that are not subject to galling, to reduce problems should contact occur. Wear ring features may include labyrinths, water injection, inspection ports, adjustment mechanisms etc. Pumps handling light slurries may make use of wear rings, sometimes with water injection to reduce wear from the slurry. Pumps handling heavier slurries usually just use pump-out vanes. Slurry pump impellers must be designed to resist wear and tear, and this requires some pumping efficiency features to be sacrificed. For example, vane edges will be blunter, vanes and shrouds will be generally thicker, and the number of vanes will be decreased in order to open up the channels between them. Passages through slurry pumps, including impeller vane spacing, are larger than for clear water pumps. Open impellers are sometimes used for very stringy materials, but tend to be weak and wear quickly, and so are not very common. Vane shape is obviously a major element of impeller design. Two critical factors are the blade entry angle (ß1) and blade exit angle (ß2), as measured between the centre-line of the vane and a tangent to the inner or outer diameter (respectively) drawn from their tips, in the oppo site direction to rotation. Most modern pumps have impellers with ß2 smaller than ninety degrees – ie backward-curved blades. Theoretically, a forward-curved blade would give higher head, but at less efficiency. Some pumps have ß2 at ninety degrees, and these are sometimes referred to as â€Å"expellers†. Many clear-water impeller designs rely on close running clearances between vane tips and casing to minimise recirculation from one â€Å"vane chamber† to the next, and maximise efficiency. Even small amounts of vane tip wear can have an effect on head and overall efficiency. The outer and inner vane tips should be sharp, not rounded or chamfered. Replacing a pump which is too large for its duty can be a major exercise. It usually requires changes to the foundations, drive arrangement and piping, spares holdings, and so on. A model of the ideal size may be just not available. As an alternative, in some cases it may viable to install a reduced-diameter impeller without changing other components. If done correctly, trimming the impeller will move the pump’s BEP to match the actual system operating point. The efficiency at the new BEP will be lower than the BEP with the original impeller, but higher than was being achieved in practice when operating well away from the original BEP. The performance variation can be estimated using the â€Å"affinity laws† which often apply to a specific impeller before and after machining: Flow rate: Pump head: Motor power: Q1 / Q2 = n1 D1 / n2 D2 H1 / H2 = (n1 D1 / n2 D2) P1 / P2 = (n1 D1 / n2 D2) 2 So if running at the same speed, trimming an impeller by a certain proportion will result in a corresponding drop in flow rate, a greater decrease in head produced, and an even greater decrease in the motor power consumed. However, these equations are based on several assumptions and some caution is called for. Impellers are complex three-dimensional objects and their effects on the liquid are due to other factors that are also affected by machining, beyond just the outside diameter – eg open area, discharge blade angle and so on. The following considerations should apply. ï‚ · Diameter reductions should not exceed 10%. Reductions beyond 20% are generally considered extreme. Some references state 30% as the maximum reduction advisable. ï‚ · Some overlap in the vanes should be retained. ï‚ · The angle between the vane centreline and the tangent to the outer diameter drawn at its tip should be restored to original by filing, with most filing occurring on the trailing si de of the vane.   The vanes will probably be thicker after cutting, and should be filed back to original shape, by filing on the traling side of the vane. ï‚ · Vane tips should be kept sharp, not rounded or chamfered. Outer tips should be sharpened by filing on the trailing side, and inner tips by filing mostly on the leading side.   Inefficiencies will take the form of increased disc friction, increased flow path length within the casing, and more recirculation across vane tips. Impellers apply forces to the fluid and are subject to the equal and opposite forces themselves. The typical single-suction impeller engages with fluid entering the pump and at first accelerates it axially into the pump, before diverting it into the radial direction. The impeller pushes the fluid into the pump, and at the same time pushes itself axially back toward the inlet point. Another way of looking at this effect is to consider that the impeller is mostly exposed to pressurised fluid all over the shroud surfaces, but not at the eye on the suction side. The thrust on the impeller must be resisted by the shaft arrangement, which must always include bearings capable of serious thrust loading. Double-suction pumps typically have less axial loading, but can still experience axial thrust, especially if flow is restricted more on one side due to internal differences in the pump, or restrictions in fluid supply on one side. Clean water pump designs may incorporate features to reduce this imbalance, such as having wear rings on both sides of the impeller, with the pressure within t he volume they enclose largely equalised by â€Å"balancing holes† passing right through the impeller. Another method is the use of a balancing disc. This is a disc mounted on the shaft in a separate chamber, with a geometry and clearances designed to counterbalance thrust effects. However, these are not practical for slurry pumps, which may use pump-out vanes instead, to lower the pressure toward the inner area of the non-suction shroud. Axial thrust loads usually consist of a steady state component plus dynamic fluctuations. Heavy axial loading is often associated with recirculation. Where failure occurs it is usually a result of overloading and over-heating of bearing components. Measures to correct excessive axial loading include:   Restoring BEP operating conditions (which may include selecting a more appropriate pump size or trimming the impeller)   Ensuring internal clearances / wear are not excessive ï‚ · Verifying correct bearing type and installation including clearances / pre-load To further complicate this issue of axial thrust, single-suction pumps handling fluids with a high suction head may experience thrust on the impeller in the opposite direction, away from the inlet. And then there are pumps with highly variable duties and suction conditions that may experience impeller thrust in different directions at different times. Shaft The shaft transmits mechanical power to the impeller from the driving motor or engine. It must also support the impeller and restrict its axial and radial movement. The loads on the shaft include self-weight of the rotating components, torque, and forces transmitted to / from the fluid. Design of a shaft requires consideration of maximum allowable deflection, the span or overhang, the location and direction of all loads, any temperature variations, and the critical speed. Loads are normally at their maximum on start-up. All objects have a natural frequency at which they will vibrate after being struck. Machines made of several components with complex shapes normally have several natural frequencies, some of which dominate. In the case of pumps, if the rotational speed of the impeller matches a dominant natural frequency, small imbalances may be amplified to a level where they interfere with operation and/or reliability. These are known as â€Å"critical speeds†. Steady operating speeds between 75% and 120% of the first critical speed should be avoided. Pumps with longer overhang on the shafts have lower critical speeds. Shafts are referred to as rigid or flexible, according to whether the running speed is lower or higher than the first critical speed. Pumps with a flexible shaft must pass through a critical speed on each start-up. This is not usually a problem because frictional forces with the fluid and the bearings act as dampers for a period sufficient for transition through the critical speed. Pumps with speeds below 1750rpm, which includes most slurry pumps, are usually of the rigid-shaft design. The shaft must be designed so that any deflection will not bring moving parts into contact, for example at wearing rings, or cause non-concentricity in critical areas such as the shaft seal. As a general rule, shaft deflection should not exceed 0.15mm even under the most extreme conditions. Deflection and critical speed are related stiffening a shaft to reduce deflection will also raise its critical speed. For pumps with overhung impellers, as is the case for most slurry pumps, this often results in the shaft diameter between bearings being quite large. The fluid passing through a pump creates a hydrodynamic bearing effect, known as the â€Å"Lomakin Effect†. That is, to some extent, the impeller rotating in the casing with fluid present is like a shaft rotating in a journal bearing with oil present. The result is that the shaft is better supported when running than when idle, so that the shaft deflection will be less, and the critical speed of the shaft assembly will be higher. However, the Lomakin Effect varies with pump head and internal clearances, both of which diminish with wear. Therefore the effective critical speed may be expected to decrease with time in service. To allow assembly, shafts step up in diameter from coupling to bearing to impeller, so tha t any torque problems are very likely to appear first at the coupling rather than the impeller, at least in single stage pumps. Shaft Seal and Sleeve The shaft connects the drive to the impeller, and so must pass through the pressurised casing. Achieving a reliable seal between shaft and casing is one of the most problematic areas in pumping. Centrifugal pumps have two types of seals – mechanical seals and packing seals. Many designs of mechanical seals have been attempted for slurry pumps, without comprehensive success, and the remainder of this discussion concentrates mainly on packing seals and stuffing boxes. Note, however, that packing is only suitable within pressure and temperature limitations. Depending on pump design and duty, the seal may need to prevent either air ingress into the casing, or fluid egress out of the casing or both of these at different times, if operation is variable. Many casings are designed with the seal area built into a compartment configured to improve sealing performance. For mechanical seals, this compartment is usually referred to as the â€Å"seal chamber†, while for packing seal s, it is known as the â€Å"stuffing box†. Slurry pump seals usually consist of several rings of packing fitted in a stuffing box around the shaft, often with provision for grease lubrication or water injection to reduce friction and provide additional sealing (particularly for when the pump is stopped). There are many stuffing box design variations and many types and configurations of packing. Stuffing boxes will accept a number of rings of packing, with a packing ring or throat bush preventing extrusion into the casing, and a gland (sometimes called a â€Å"follower†) used to adjust packing compression. A lantern ring may be substituted for one of the packing rings, to cater for injection of grease or sealing water, water being particularly required if air would otherwise be sucked into the fluid stream at this point. Sealing water (or an alternative clean liquid) is usually required for: Slurries   Liquids for which leakage is not acceptable   Liquids that are not suitable for sealing purposes   Suction lifts greater than 4.5m (air ingress may interfere with priming)   Discharge pressures above 70kPa The packing must be placed under some compression and this tends to result in wear on the shaft, which is often sleeved to avoid having to replace the entire shaft once wear is advanced. There are numerous designs of shaft sleeves. The shaft sleeve must be resistant to friction and heat, and several different materials and surface treatments are available – eg hardened high-chrome stainless steel, ceramic, plasma spray or tungsten carbide coating etc. To prevent chipping, coatings should not extend to the edges of the sleeve. The sleeve does not contribute to strength, so the shaft itself must be large enough to carry all the loads, and this means that including a sleeve in the design enlarges the seal diameter. For small pumps, this may decrease pumping efficiency and raise the purchase cost to the point that sleeves may be abandoned and a stainless steel shaft used instead. Glands may be solid, or split to allow replacement without disassembly of pump or bearing assembly. They are usually made of bronze, cast iron or steel. Special designs are used to improve safety if the fluid is hazardous. The leakage of fluid past the packing is controlled by tightening the gland, compressing the packing axially and expands it radially so that leakage paths along the shaft sleeve are constrained. However, some fluid flow between packing and sleeve is usually needed to avoid overheating the packing and damaging the sleeve surface. Once the sleeve surface is damaged, the sealing efficiency decreases and more tightening is required, further damaging the sleeve, and so on. The secret is to provide a configuration of packing and seal water injection that suits the application, and then avoid over-adjustment. To further reduce the pressure at the shaft seal area, where the rear pump-out vanes are not sufficient, some slurry pumps are fitted with a second smaller open-faced impeller, usually called an â€Å"expeller†. Many different designs have been tried. If sealing water is used, there will be a design intention regarding the ratio of water to pass in to the volute compared to out past the gland follower. This can be controlled using the number of packing rings on each side of the lantern ring, but the lantern ring must be installed at the injection point. For clean water pumps, this seal water is sometimes provided from the pump discharge. Clean water must be used to avoid contaminating the packing with grit – filtration or cycloning may be necessary if the water contains some grit. When managing sealing arrangements, thought must be given to what happens when the pump is stopped. The pressure in the stuffing box changes to static conditions, which may result in slurry leaking into the packing and contaminating it, causing rapid sleeve wear on re-starting. But if sealing water continues to be applied, the slurry may be diluted, and eventually a sump can be filled with sealing water if left idle for a long time. For prolonged stoppages, sumps may be best dropped, for various reasons. On restarting, sealing water supply should start before the pump starts. Stuffing boxes in extreme applications may be provided with galleries through which cooling water can pass to prevent excessive temperatures around the packing. In applications where leakage must be more precisely controlled, or where elevated temperatures in the seal area must be avoided (for example where the fluid is volatile), mechanical seals may be suitable, provided that the fluid is not damaging to the seal components. A comparison between mechanical seals and packing seals is given below. ï‚ · Packing seals: o Low initial cost o Tend to deteriorate gradually o Easily replaced when necessary o Can handle large axial shaft movements o Always some leakage required o Require regular adjustment o Not suitable for hazardous / volatile fluids o Often cause progressive shaft sleeve wear o Can result in significant shaft power losses o Limited to low pressures and speeds ï‚ · Mechanical seals: o Minimal or zero leakage o No adjustments required o Suitable for hazardous / volat ile fluids o No shaft wear o Do not consume significant shaft power o Can handle high pressures and speeds o Tend to fail suddenly o Replacement requires pump disassembly o High initial cost Packing seals work as a result of axial compression, so that the packing rings extrude outward and apply radial pressure to the adjacent components, these being the static surface of the stuffing box, and the rotating shaft sleeve. A dynamic seal is formed between the packing rings and the sleeve surface, with some fluid flow between the two being necessary for lubrication and cooling. For clean water pumps, this fluid may be supplied from the inner end of the stuffing box, or from the discharge pipe via small diameter piping. In the case of slurries, grit in the fluid would add to friction and wear, so the lubricating and cooling fluid is usually injected from a separate clean water supply. The injection pressure should be 10 to 25psi greater than that at the inside end of the stuffing box, and this figure should be available from the pump designer. A rule of thumb is to set the gland feed water pressure to between 35 and 70kPa above pump discharge pressure. Pressure regulation is often helpful. In theory, some slurry pumps should operate with a pressure at the inside of the stuffing box which is below atmospheric pressure, so that the packing is required only to prevent air ingress into the pump. However, when the pump is turned off, or in abnormal operating conditions, slurry can pass back into the seal and contaminate the packing with grit, so these situations still call for water injection. Grease or oil may be used instead of water in some applications. Packing material must be able to withstand the operating environment and remain resilient to perform satisfactorily despite minor shaft misalignment, run-out, wear and thermal expansion / contraction. Packing is available in a huge range of materials (lubricant, binder and fibre / matrix) and in many sizes, shapes, and constructions, to suit different applications – particularly size, shaft speed, temperature, pressure, and chemical resistance. The number of packing rings varies between applications, the most common arrangement being throat bush or ring, three inner packing rings, lantern ring, two more packing rings, and gland follower. The lantern ring may be placed further in, to reduce slurry ingress. Packing size is usually proportional to shaft / sleeve outer diameter, as follows: Shaft / Sleeve OD (mm) 15 to 30 30 to 50 50 to 75 75 to 120 120 to 305 Packing Size (mm) 6 8 10 12.5 16 Shaft sleeve finish needs to be at least 0.4micron CLA to avoid excessive rotational friction, and the finish in the stuffing box bore needs to be at least 1.65 micron CLA to allow even compression during adjustment. The sleeve must be harder than the packing, and chemically resistant to the fluid pumped and the injection fluid. Any coating on the sleeve must have a good thermal shock resistance. The lantern ring allows for entry and distribution of the lubricant or flushing fluid. Lantern rings are usually split to allow installation and removal without pump disassembly. They were traditionally made from metal such as stainless steel, but lubricant-impregnated plastics are now common. Gland followers are also usually split to allow easy replacement. They are usually bronze but may be steel or cast iron. Special purpose gland followers are used with volatile or hazardous materials, including capacity for diluting and safely flushing away leakage. The axial compression on the packing must be occasionally adjusted to control leakage. The correct leakage rate is one drip per second. Over-tightening should be avoided as it will result in over-heating and shaft wear. Most packing is supplied with impregnated lubricant, and over-tightening will press the lubricant out. Pumps need extra sealing provisions if pressure at the inner end of the stuffing box is greater than 75psi. The use of harder packing material on the inner rings may help. The procedure for replacing packing is: 1. Read the instructions provided by the pump manufacturer and packing supplier. 2. Loosen and remove gland follower. Inspect gland follower for wear, corrosion, warping etc. 3. Remove old packing rings using a packing puller, and the lantern ring. 4. Inspect shaft sleeve surface for deterioration, and clean up where possible. Replace if necessary. 5. Inspect bore of stuffing box for corrosion, wear, scaling etc, and clean up where possible. 6. Verify correct packing size to be used. 7. Tightly wrap the correct number of packing coils around a mandrel of equal diameter to the shaft sleeve. 8. Cut each ring at an oblique angle. 9. Install each ring, staggering the joins 90 degrees on subsequent rings. Suction / Intake Design Centrifugal pumps operate most efficiently when the liquid to be pumped flows into the inlet nozzle in a smooth, uniform manner with minimal turbulence. Suction systems need to be designed to ensure that this happens. The most common problems are: ï‚ · Uneven / turbulent flow ï‚ · Vapour collection ï‚ · Vortex formation Suction piping should be as short and straight as possible to minimise friction, and if unavoidably long, should be of large diameter. The suction line will normally be at least one pipe size larger than the pump inlet flange, requiring fitment of a reducer. A reducer should not change the pipe bore by more than 100mm. Fluid flow should be as uniform as possible right up to the pump inlet flange. There should not be any fittings likely to cause turbulence, sudden changes in flow direction or spin within ten pipe diameters of the pump inlet flange. There should be no short radius elbows at all, and no long radius elbows within three pipe diameters. All suction line connections need thorough sealing to prevent air being drawn in. For suction manifolds serving multiple pumps, all the above points apply, and branches should be angled at 30 or 45 degrees, rather than ninety degrees, and sized so that fluid flow is constant throughout. Flow should not exceed 0.9m/s. Improper suction conditions or designs can result in the fluid swirling as it approaches the pump through the suction pipe. This is called â€Å"pre-rotation†. It causes a drop in pumping efficiency because the pump is designed to process fluid that is entering without rotation, and can cause additional suction pipe wear. Sometimes a radial fin is fitted to the suction pipe or casing to reduce pre-rotation. The suction pipe design should cater for elimination of air from the suction line, and prevention of vapour pockets, in the simplest manner, meaning that: ï‚ · For pumps with the feed being drawn from a level below (eg a dam pump), o Suction pipe should have a slightly upward slope toward the pump o The eccentric reducer should have the flat side on top ï‚ · For pumps with the feed being drawn from a level above (eg a thickener underflow pump), o Suction pipe should have a slightly downward slope toward the pump Vortexing in feed tanks needs to be avoided to prevent air being drawn down into the pump. Baffles may need to be fitted to tank walls. The tank fluid level needs to be kept well above the suction inlet. Bearings Bearings provide axial and lateral restraint to the pump shaft and attached components, while allowing free rotation. Axial loading on pump shafts may be significant as discussed separately, and the bearing arrangement always includes some thrust capability. The bearings most commonly used are deep-groove single row ball bearings, and single or double row angular contact ball bearings. Pumps may be in overhung configuration, where the shaft is supported by bearings on one side only, or have a shaft that passes right throught the casing with bearings on both sides. Most slurry pumps are of the overhung design. The bearings are usually rolling-element, but plain journal bearings are sometimes used on larger pump sizes. The bearings must be lubricated by grease injection or oil bath and may need provisions for cooling as well. This may be by having a cooling water jacket integral with the bearing housing, or by pumping the lubricating oil through a heat exchanger and filter. Oil lubrication is usually recommended rather than grease, if speed exceeds 5000rpm (which is very rare in a slurry pump). Grease-packed bearings should have one third of the chamber filled with grease. Oil baths should be filled to the centre point of the lowest rolling element. Inadequate loading of bearings can result in the rolling elements skating over the race instead of rolling, and this can cause heating and failure. To avoid this, bearing assemblies are usually designed with an assembly configuration, including preload, that ensures all bearings carry some load. Frame and Foundations For large pumps that are directly connected (ie no vee-belt drive), the motor and pump are usually mounted on the same bed-plate, which is fixed to the foundations in a way sufficient for eliminating looseness and distortion. This eliminates some misalignment issues at the source. Foundations including bed-plates should be checked occasionally for deterioration (corrosion, ground subsidence, concrete cracking, loose fasteners, missing grout etc), and the alignment between pump and motor should also be checked if there is any cause for concern. The framework should have provisions for drainage of any spillage and seal leakage etc, so that this does not become trapped and contribute to corrosion etc. Where pumps operate at high temperature (ie above around 100C) the pump casing should be supported at its axial centre-line, to help reduce thermal stresses. It is generally preferred that all suction and discharge piping have its own supports, so that the pump casing and foundations do not carry any significant static or dynamic piping loads, and so that pump components can be independently removed and replaced. Where this is not the case, extra pump and foundation attention may be needed at the design stage. Drive Arrangement Many drive arrangements are possible to suit the circumstances. Electric motor drive is the most popular, followed by internal combustion engines. Variable speed drives are sometimes necessary and often convenient, but always more expensive and less reliable. In minerals handling plants, slurry pumps are most often electric motor driven, with belt drives. Belt drives allow speeds to be changed through minor modifications – ie pulley changes. Short, low head slurry system designs usually provide motors that are 10 to 20% oversized, to cater for any under-estimates in slurry or system characteristics such as viscosity and friction, and to allow for minor system modifications during the service life. Instrumentation Pumps may be controlled to allow: ï‚ · Variation of flow rate, pressure, liquid level ï‚ · Protection against damaging operating conditions ï‚ · Flexibility in matching pumping performance to duty For centrifugal pumps, control is usually accomplished by speed setting (including turning off/on), or valve setting. This may be manual or automatic. For slurries, control by throttling valve is rare due to the wear rates that usually result. Typical instrumentation includes: ï‚ · Tank / sump level switches ï‚ · Pressure sensors ï‚ · Flow sensors ï‚ · Density sensors In each case, protection from damage by the slurry is critical. This is commonly achieved by using sensors that do not need to contact the slurry eg nucleonic density sensors mounted outside the pipe, with source on one side and detector on the other. Ideally, it is good to have instrumentation available, either permanently mounted or portable, to: Verify operation at BEP, by measuring the difference between suction and discharge pressure Determine flow Ensure that NPSH is sufficient to prevent cavitation Compare flow to motor amperage, to identify when impeller adjustment is needed Need to search more on valves for slurry applications. Notes on Material Selection Where there is some chance of parts coming into contact during pump operation, thought should be given towards minimising the damage that may result. An example of this is at the wear-ring / impeller interface. Studies have shown that damage can be minimised by manufacturing adjacent components from materials that:   Are dissimilar, except where known to be resistant to adhesive wear and galling   Have a difference in hardness of at least 10Rc, if either has hardness less than 45Rc Because it may be difficult to always prevent cavitation from occurring, impellers are usually made of cavitationresistant materials such as chrome-manganese austenitic stainless steel, carburised 12% chrome stainless steel, cast nickel-aluminium bronze, etc. Obviously corrosion resistance is another key selection factor that these materials satisfy. Slurry pumps are subject to heavy wear in the form of abrasion and erosion. The aggressiveness of the slurry is determined by the hardness of the particle s in the slurry, their shape (rounded or sharp), the pulp density, and the size distribution. Slurries can become less aggressive as they travel through a minerals processing plant as the sharp edges become rounded off. Velocity and angle of impingment are also very important factors affecting the resultant wear rates, with wear rate being proportional to velocity squared according to some references. The impingement angle associated with maximum wear rate seems to be dependent on the hardness and brittleness of the material being struck. For very hard / brittle materials it is between 65 and 90 degrees, while for more ductile materials it may be around 25 degrees. Pumps handling slurries with greater than 6mm particle size are usually lined with rubber. However, if impeller tip speed exceeds 28m/s, rubber becomes subject to thermal degradation, and this usually restricts the use of rubber to a maximum head of 30m per stage. Metal lined pumps may be used up to 55m head per stage. For wet end components, materials that may be used to resist wear include Ni-resist, carburised and hardened 12% chromium steel, etc. White iron slurry pump components, which includes Ni-Hard, are restricted to impeller tip speeds of about 36m/s to avoid maximum disc stresses. Steel components are softer but can run at higher speeds, up to a tip speed of 45m/s. Centrifugal pumps are subject to cyclic loads due to such things as imbalance, unbalanced radial forces, fluctuating axial thrust, the vibration induced as each vane passes the cut-point, and variations in upstream and downstream fluid pressure and flow. This sets the scene for fatigue loading, which becomes more of an issue if the slurry is corrosive. Fretting may occur between assembled components where looseness is allowed to develop. This is best avoided through the use of correct manufacturing dimensions and surface finishes, good fitting practice etc. The materials commonly used for pump components include:   Impellers (require castability, weldability, and resistance to corrosion, abrasion, and cavitation) o Bronze, for non-corrosive liquids below 120C o Nickel-aluminium bronze, for higher speed and mildly corrosive applications o Cast iron, for small low-cost applications o Martensitic stainless steel, where added resistance to cavitation, wear, corrosion (other than salt water) or high temperatures may be required o Austenitic stainless steel (mostly cast 316 grade), where a higher level of corrosion resistance is needed. Austenitic stainless steel with 6% molybdenum is often used for salt water pumping.   Casings (require strength, castability and machinability, weldability, and resistance to corrosion and wear) o Cast iron o Cast steel, where extra strength is required ie for pressures above 6000kPa (1000psi) and temperatures above 175C. o Austenitic cast irons with 15 to 20% nickel (Ni-Resist) may be used where abrasion and corrosion are issues. o Bronze, for water applications o Stainless steel, where corrosion is a major issue – martensitic for higher pressures in mildly corrosive fluids, austenitic for more aggressively corrosive fluids. ï‚ · Shafts (require resistance to fatigue and corrosion) o Mild steel, where corrosion and fatigue are minor issues Low alloy steel such as 4140 for added strength Martensitic stainless steel, where added strength and corrosion resistance are needed Shafts are usually chrome-plated, and care is needed to avoid this adding to the fatigue susceptibility through micro–cracking and hydrogen embrittlement. Shafts can be shot-peened prior to plating, and heat-treated afterward to reduce these effects. Wear rings (require castability and machinability, and resistance to corrosion, abrasion and galling) o Bronze for clean liquids and temperatures up to 120C o Stainless steel for applications with abrasion, corrosion and high temperatures – but steps must be taken to avoid galling should the rings come into contact eg increased clearances, hardness differences etc. o o o Impellers other than those made from martensitic stainless steel can usually be repaired by welding, although in some cases this needs to be followed by specific heat treatment processes. In all cases, more exotic (and expensive) materials may be used for specific applications. Material selection is often a balancing act between optimising purchase cost and maintenance / operations performance. Where high temperatures are involved, material selection must take into account differences in expansion rates. Unlined slurry pump impellers and casings are often made from abrasion-resistant cast irons as per ASTM A532, which includes Ni-Hard. These materials consist of a martensitic matrix with secondary hard phases of chrome and iron carbides that increase wear resistance. They cannot be machined or welded, and tend to be prone to corrosion, and breakage through mechanical impact and thermal shock. Brittleness may be reduced by annealing, but this reduces wear resistance. Slurry pump impellers and casings may be lined with softer materials like rubber, where high temperatures can be avoided. These can reduce wear rates by absorbing the impact energy of the particles, while resisting corrosion. Problems may arise in bonding of the rubber at the cut water point, and on the impeller. The lining reduces the thickness of the metal section of the component, so stronger materials are usually used eg steel rather than cast iron. Manufacturers develop their own specifications for ideal liner thicknesses based on experience, but one reference suggests a volute liner thickness of 4% to 6% of impeller diameter. Natural rubbers seem well suited for wear liners for use with slurries with less than 6mm particle size for the impeller, and 15mm particle size for the volute. Provided the base materials are suitable, patches of high wear on wet end parts can sometimes be repaired by welding / hard-facing. However, this increases the likelihood of cracking. Also if the welding results in uneven surfaces in critical points, the added turbulence can accelerate further wear. Many types and styles of surface coating have been tried, with some success. These include thermal spray coatings, diffusion surface treatments, spraying and trowelling of epoxies, etc.