Contemporary Strategy Analysis Text and Cases Process

Question: Discuss about the Contemporary Strategy Analysis for Text and Cases Process. Answer: Introduction The report focuses to analyse competitive position of the US airlines industry. US airline industry is facing some challenges in recent times in terms some low profitability, higher fare charged by major airlines, losing investors faith, labour crisis. Domestic demand for the air transport is US is high due to geographical distances between major cities (Cederholm 2014). Air fare in US has increased overtime due to increasing demand from both domestic and international sectors. In order to address issues faced by the US airlines, the report makes a competitive analysis; which includes porters five forces analysis. This analysis includes bargaining power of the consumers, bargaining power of the suppliers, competitive rivalry in the industry, presence of threats of substitutions and threats of new entry in the market. US airlines have large scale of operation in the global airline industry. PESTLE analysis highlights the political, economic, social, environmental and legal impact on the airline industry. US airlines have their internal problems, which are discussed trough SWOT analysis. SWOT analysis highlights internal strength, weakness, opportunity and threats in the market. US economy has undergone terrorist attack, financial crisis, economic recession, and rise in fuel price and demand crisis during twenty first century, which has impacted negatively to the US airlines industry (Koenig and Mayerowitz 2015). This report presents a strategic analysis to increase profitability in the airline industry. An overview of the US airline industry There are more than 100 certified passenger airlines operating in US with more than 11 million flight departures every year. US airlines transport about 2million passengers and 50,000 tons of cargo every day (airlines.org 2016). Political factors Price regulations, business regulations, competition policy of government, political instability due to change in government, affect the operation of airlines (Cederholm, 2014). Trading agreement with different countries affect the profitability of business. Regulations in labour market affect the cost of operation in the airline industry. Economic factors Pattern of consumer spending, demand for air travel from both domestic and international passengers affect the profitability of airline industry. Rising inflation, fluctuation in exchange rate, decreasing consumer spending due to economic recession affect the business of airlines (airlines.org 2016). Rise in fare of each airline depends on the respective demand and capacity of each aircraft. Monetary policy affects the interest rate, which further affects investment in airline operation and infrastructure (Orphanides 2012). Federal open market committee has long term goal such as maximising employment, moderate rate of inflation rate. As inflation has inverse relation with the interest rate. Therefore, rise in inflation reduces inflation rate in US facilitating the investment in airline industry (federalreserve.gov 2016). Lorenzetti (2015) argued that global financial crisis at inflation have resulted into greater economic instability, high inflation and slower growth of economy leading to low profitability in US airlines industry. US airlines contribute significantly to the domestic economy in terms of share in GDP, employment. Technological factors Technological advancement improves airline operation in terms of cost reduction. Advanced air craft engine technology, IT solution, mobile technology has improved US aviation industry significantly (Aguirregabiria and Ho 2012). Technological up gradation enhances the capacity of the aircraft, enhances the comfort of travelling, creates better connectivity and reduces fuel consumption. All these factors positively influence the consumer demand. Legal factors Environmental and work place safety law affects the business operation of airlines. US airlines are regulated industry. US airlines needs to maintain energy security regulations and aviation safety law (airlines.org 2016) Social factors Global recession of 2007-08 and 2013-14 have great impact on US economic. US economy has been slowed down after the global recession. Therefore, consumer spending on travel and tourism has reduced after 2011, which has negative impact on the profitability of US airline industry (Dai, Liu and Serfes 2014). Environmental factors High fuel cost is a reason of low profitability. Use of renewable energy and low fuel consumption are growing issue sin airline industry. The airlines such as Delta, United, American, Southwest, and Jet Blue have been replacing the old aircraft with new fuel efficient ones in order to reduce impact on climate change (Puller and Taylor 2012). A competitive forces analysis of the airline industry Strengths Large number of employees and technological innovation are strength of US aviation industry. Variety of planes gives opportunity to passengers for the choosing aircraft as per their choice. Product differentiation gives competitive advantage to the companies of different companies of US airline (Dai, Liu and Serfes 2014). High domestic demand for the fleet of 330 + mainline jet aircraft and rising demand from international travellers. These factors are contributing factors for rising revenue. Koenig and Mayerowitz (2015) stated that merger of nine large US airlines to four has reduced global competition in the airline industry by raising monopoly power of the US airlines. Weakness Rising labour cost in the US economy is an important concern for the airline industry as it raises cost of operation. Rising labour cost creates pressure on airline service and hence on the profitability of the company (Barla 2013). US airlines have leased some of the planes, for which large amount of money have been spent. Most of the planes have not been utilised properly (Zou et al. 2014). US airlines have been affected by terrorist attacks various times. These incidents have hampered the scale of operation making loss for the airlines. Opportunity Most of the companies of US airlines have good infrastructure and opportunity to increase profits. Merger and acquisition gives US airlines an opportunity to dominate market (afacwa.or 2015). US airlines have opportunity to us point to point flying instead of hub-spoke flight pattern. Profitability in point to point flying is more than the later one (Belobaba, Odoni and Barnhart 2015). There is immense opportunity to make a partnership with a financially stable company Threats Economic turmoil and political unrest in domestic economy has negative effect on airlines profitability. Entry of new company is always there in the airline industry of UK. Oil price fluctuation has impact on the fuel price and hence on the demand for air transport as there is alternative transportation route for domestic travel (Johnston and Ozment 2013). There is always a possibility of terror attack in future to affect airline business. Five forces of Porter Power of supplier: Supplier in US airline has immense power to bargain over inputs such as fuel, labour and aircraft. Airlines companies are potential buyers of the inputs and there is rising competition in this industry. Competition among buyers gives suppliers sufficient power to bargain over the price of each input (Borenstein and Rose 2014). Fluctuation in oil price in the international market, rise in wage through the bargaining power of labour union, increase in the price of aircraft affects the input cost of the US airlines. Power of buyer: Online ticketing system facilitates the buyers so that they no longer need to depend on the agent and intermediaries. Entry of low cost carriers and price war among the airline companies in provides the scope of bargaining to the consumers (Grant 2016). This is the form of indirect bargaining. A consumer generally fills the ticket for low cost carrier. Hence, it is hard to raise fare above competitive price as the consumer may search for alternatives. Hence, power of buyers is said to be high in this industry. However, Aguirregabiria and Ho (2012) mentioned that recent mergers of large airline companies of US give them a monopoly power to charge a higher fare to the consumers. Entry barrier: Any potential firm can enter into this industry due to presence of positive profits. However, entry is not easy, as a company needs huge start up capital in order to operate and establish business in this industry. The scale of operation in this industry is large. Moreover, knowledge, skill and huge investments are required to run the business (Brueckner, Lee and Singer 2013). Hence, it can be said that entry in airlines in restricted. Threats of substitutes: Close substitute is available for US airlines. Rail, road and waterways are available for transportation within different provinces of US. Waterways are available for international transport. Threats of substitute is high for domestic transport, however, it is low for international travel. Intensity of rivalry: Intensity of rivalry is high in this industry. There are around 100 of passenger airlines in US economy. Therefore, competition in this industry has at high level. Tight regulations, high operating expenses, rapid rate of turnover make the industry more competitive (Ciliberto and Williams 2014). Economic performance analysis Airline industry has significant impact on the US GDP. This industry contributes more than 10 million jobs every year. This industry also contributes 5% of each dollar of GDP of this country. This sector supports other allied sector such as tourism and hotel industry to help the economy to boost. All these factors contribute to economic growth of this economy. US passengers and cargo carriers in the airline industry employ more than 682000 employees worldwide. Along with recruitment opportunity, this industry provides security, handsome payment and benefits to employees. Average wage of the employees of US airline is $67,000 compared to national private sector average $45000 (airlines.org 2016). Therefore, it can be said that the standard of living of the family of airline industry is better compared to other sectors. There are several types of job opportunity and thus numerous skills of employees are required. Hence, this industry encourages government investment in the education se ctor more for human capital formation (Borenstein and Rose 2014). Contribution to local economies Airlines influence other domestic sector through backward and forward linkages. Airlines connect different geopolitical regions easily increasing economic cooperation and trade agreements. This sector facilitates businesses, direct and indirect commerce. Investment in airline infrastructure facilitates cargo transport, which further facilitates export and import in US economy with rest of economies (airlines.org 2016). Growth in export- import contributes in economic growth. Moreover, this sector indirectly acts for growth of the economy by facilitating the tourism sector and hotel industry. Moreover, suppliers of aircraft and aircraft parts are benefitted for the growth of this industry. Demand analysis Demand for airlines comes for business purpose and for tourism. Demand comes from several business sectors, students and families. However, demand for passenger transport is high from the business organisations for international meeting. During 2015-16, revenue of the airlines has decreased. Demand in this industry falls during economic recession as people cut their expenses on travel and tourism. The causes of decreasing revenue in recent times are foreign exchange pressure and lower surcharges in the international market (Lorenzetti 2015). Demand for US airlines is high during boom period, when production of goods and services in domestic economy is sufficient. The excess amounts of products are exported to diversified global market. As US airlines are important medium of cargo transport, demand for important airlines in US are high at economic boom and recovery period. However, decline in oil price has helped the airlines to take cost saving initiatives and reduction in ticket price. Rising incumbent in this industry over the years has created excess capacities in this industry and rising competitiveness. As stated by Schmidt (2015), increase in capacity in the airlines was more than the demand during 2014-15 in US. Strategies for airline profitability Despite huge growth of passenger demand, airlines of US face decreasing revenue in recent days. Increasing labour cost, increasing competition, weak industry profit margin is main cause of decreasing profitability. Major airlines of US have merged with each other during previous decades to raise market power. However, new entry in the market is still creating excess capacity in the industry, which is creating pressure on the existing airlines such as Delta Air Lines, United Continental, American airlines, JetBlue Airways (Aguirregabiria and Ho 2012). One strategy of the airlines to increase profitability may be investment in ancillary services of airlines such as early boarding, Wi-Fi, baggage and premium seating. Cost leadership gives competitive advantage to the airlines. Use of low cost fuel and low cost- technology enabled air carriers can reduce cost of operation. Collaboration with the suppliers and proper negotiation with the labour union can mitigate the problem of increasing input cost. Cost leadership helps to keep price low compared to the competitors. This strategy creates barriers to the entry of new firm in this industry (Puller and Taylor 2012). Split between luxury and economic seating classes give passages opportunity to choose according to their choice and demand. Price discrimination along with product discrimination can be effective strategies. Lease of airlines Many of the US airlines have faced debt burden after their merger with other airlines. American Airlines had $16.8billion of debt after its merger with US Airways. Debt burden has put burden on the profitability of this airline. Debt burden and low profitability are reflected both on the balance sheet and cash flow statement. During that time, the lease value of American Airlines was $8.7 billion. Levine-Weinberg (2016) stated that leasing is equivalent to debt as it requires long term stream of payment. However, Delta Airlines on the other hand chose to use capital spending for reduction of debt burden instead of leasing. The above analysis shows that the cause of low profitability in US airlines is increasing cost, rising pressure of exchange rate, rise in excess capacities and increasing competitiveness. Traditional hub-and spoke airline model is barrier for increasing profit. As there is number of substitutes of airlines in US economy for domestic transport, rise in fare shifts the demand from airlines to other mode of transport (Johnston and Ozment 2013). The hub and spoke airline model is not competitively sustainable as this requires extensive physical infrastructure, complex aircraft fleet, and large number of labour. Point to point flying model is more effective as it provides short trip facilities. US airlines have experienced major loss in revenue several times due to bankruptcy, global recession, and financial crisis. Nine large airlines have been merged up to become four major airlines such as American, United, Delta and South West to increase market share and to reduce cost of operation before 2010. During the same period, airfare has risen more than the inflation rate due to decrease in competitive pressure. The merger has been seemed to be successful that US airlines made $19.7 billion profit. Koenig and Mayerowitz (2015) mentioned that demand has increased despite rise in fare due to investment in capacity enhancement such purchase of new jets and improvement of airport facilities. Moreover, collusion strategy has been taken to increase fare and decrease number of available flights and seats. Another concern in recent times in US airlines is violation of competition rules. Lorenzetti (2015) mentioned that employees of major US airline such as Southwest airlines. Delta is facing problems with upper management in terms of better pay, rejection of labour contract. Decreasing stock price is another major concern for low profitability. As a consequence, the investors are losing faith from airlines and uncertainty in the investment opportunity is increasing in this industry (Grant 2016). Therefore, it is recommended that change in business strategy, cost leadership policy, coloration with strong financial company can be beneficial for the airlines. It can be said from the study that economic condition of US airlines can be said to be cyclical as the fluctuations in profitability move in the line with business fluctuation. Recession, boom period both have their respective effect on the airline industry of US. Conclusion The report has highlighted different aspects of US airline industry such as competitive strategy, economic contribution on local and global economy. The study has found different reasons of fluctuations in revenue and profit in the airline industry. Increasing capacities due to technological improvement has increased demand for airlines. Merger of nine big airlines in US has created monopoly market in US aviation industry. Therefore, airfare has increased in US significantly due to decrease in competitiveness. Moreover, enhancement of capacities, increasing number of jets is contributing factors for rising demand. Increase in demand raises revenues of US airlines. Despite that profitability of the airline industry has fallen due to increasing labour and other operating costs. Cost leadership may be a strategy to overcome the challenges in the US airline industry. References afacwa.or (2015). US airline industry overview June 2015, https://www.afacwa.org/us-airline-industry-overview-june-2015 Aguirregabiria, V. and Ho, C.Y., 2012. A dynamic oligopoly game of the US airline industry: Estimation and policy experiments.Journal of Econometrics,168(1), pp.156-173. airlines.org (2016). Regulatory Barden. Available at: https://airlines.org/policy-priorities-learn-more/#regulatory-burden airlines.org (2016). Is a criticaleconomicengine. Available at: https://airlines.org/industry/#economicAIERVIEW: JUNE 201 Barla, P., 2013. Market share instability in the US airline industry.Journal of Applied Business Research (JABR),15(4), pp.67-80. Belobaba, P., Odoni, A. and Barnhart, C., 2015.The global airline industry. John Wiley Sons. Borenstein, S. and Rose, N.L., 2014. How airline markets work or do they? Regulatory reform in the airline industry. InEconomic Regulation and Its Reform: What Have We Learned?(pp. 63-135). University of Chicago Press. Brueckner, J.K., Lee, D. and Singer, E.S., 2013. Airline competition and domestic US airfares: A comprehensive reappraisal.Economics of Transportation,2(1), pp.1-17. Cederholm. T., 2014. Must-know: External factors that influence the airline industry. Available at: https://marketrealist.com/2014/09/must-know-external-factors-influencing-airline-industry/ Ciliberto, F. and Williams, J.W., 2014. Does multimarket contact facilitate tacit collusion? Inference on conduct parameters in the airline industry.The RAND Journal of Economics,45(4), pp.764-791. Dai, M., Liu, Q. and Serfes, K., 2014. Is the effect of competition on price dispersion nonmonotonic? evidence from the us airline industry.Review of Economics and Statistics,96(1), pp.161-170. federalreserve.gov. (2016). Statement on Longer-Run Goals and Monetary Policy Strategy. Available at: https://www.federalreserve.gov/monetarypolicy/files/FOMC_LongerRunGoals_20160126.pdf [Accessed 18 Dec. 2016]. Grant, R.M., 2016.Contemporary strategy analysis: Text and cases edition. John Wiley Sons. Johnston, A. and Ozment, J., 2013. Economies of scale in the US airline industry.Transportation Research Part E: Logistics and Transportation Review,51, pp.95-108. Koenig, D., and Mayerowitz, S., 2015 Analysis: Consolidation of U.S. Airline Industry Radically Reducing Competition. Available at: https://skift.com/2015/07/14/analysis-consolidation-of-u-s-airline-industry-radically-reducing-competition/ Levine-Weinberg, A., 2016 Does American Airlines Have Too Much Debt? Available at : https://www.fool.com/investing/general/2016/05/16/does-american-airlines-have-too-much-debt.aspx Lorenzetti, L. 2015. Here's Why The Airline Industry Is In For A Rough Ride. Fortune.com. Available at: https://fortune.com/2015/08/19/airline-industry-challenges-ahead/ [Accessed 18 Dec. 2016]. Orphanides, A., 2012. Whats wrong with current US monetary policy? Available at: https://www.weforum.org/agenda/2015/11/whats-wrong-with-current-us-monetary-policy/ Puller, S.L. and Taylor, L.M., 2012. Price discrimination by day-of-week of purchase: Evidence from the US airline industry.Journal of Economic Behavior Organization,84(3), pp.801-812. Zou, B., Elke, M., Hansen, M. and Kafle, N., 2014. Evaluating air carrier fuel efficiency in the US airline industry.Transportation Research Part A: Policy and Practice,59, pp.306-330.

Sample Paragraph Essay on Odysseus

Sample Paragraph Essay on OdysseusSample paragraph essay on Odysseus is one of the most rewarding subjects to write a study on, because it not only discusses life of one particular man, but also teaches the student a lot. In this article I will briefly discuss on Sample paragraph essay on Odysseus.As you probably know, term on whom I would advise the student to write a paper on, is the term on which he/she would use when dealing with this subject. At the same time, for anyone who is now learning the English language, it is not enough just to have the right sentence structure, but also to comprehend the meaning of the whole study. In the same manner, writing a brief paragraph essay on Odysseus is quite vital, because most students have very poor comprehension skills in this subject. Therefore, they are also unable to convey their thoughts to other people.I think that if you fail to write an essay on the subject of the greatest figure in ancient history, then you will certainly fail to pass out of your University. You must always remember that not only do you not have the mastery over the English language, but you might not even be aware of it. In addition, having weak skill and concentration levels are not a good combination, so if you have poor skills and concentration, you will surely fail to pass your essay.Hence, an essay on this subject should not only be a written story, but should also be a logical writing, because if you simply concentrate on the language, the entire process will be very complicated and troublesome. You must be aware that the techniques used in writing an essay can be easily acquired by simply reading some modern English books or textbooks. But still, the quality of a writer is essential, and while you should be aware of the aspects such as style, sentence structure, grammar, proper usage of punctuation marks, etc., you must also be able to find a better way to express your ideas. I must say that this area is not as easy as it seems, esp ecially in the subject of sample paragraph essay on Odysseus.It is because the entire idea of expressing an idea of which you have knowledge is of course related to the nature of the particular person, and the situation which he/she had been in. Thus, when you are writing the first paragraph, the real story of the whole world and the individual who was involved in it, needs to be conveyed to your reader, but at the same time, in a very good way. You must therefore start by creating a rough draft on what your main points of your essay will be.This can easily be done by just looking up the main points of the study and do a recap on it. If you think that your story is too long and you want to add some information on it, try to write a short paragraph on a couple of things to conclude the whole story. In the same manner, if you feel that your essay does not quite fit into the statement of facts, start looking for a few extra facts to increase the interest level in your reading.The above paragraphs represent just a few tips that I personally recommend for people, who would like to write a whole research project on the history of ancient Greece. Sample paragraph essay on Odysseus is certainly a great topic to study and certainly provides you with more than you expected from it.

Do Drugs Cause Youth Violence Essays - Drug Culture,

Do Drugs Cause Youth Violence Do Drugs Cause Youth Violence? I believe that youth violence in America is somewhat due to the use of drugs, but not entirely. Although drugs are known to educe violent behavior, I do not believe they are the routes of violence among American teens. I think that kids can be violent with the absence of drugs. While under the influence of alcohol, one cannot understand the difference between what is wrong and what is right. They believe they are at a much more powerful level that they actually are. Emotions are much more prominent after someone has been drinking, and this may lead to random outbursts upon any one near. I've witnessed anonymous members of my family perform similar acts. The more dangerous of drugs, such as meth-amphetamine , heroin, L.S.D, P.C.P, crack-cocaine etc. are more likely to cause acts of violence over the obtainment of such substances rather than that of the users under the influence themselves. Such acts are done more among an older range of users not exactly in the youth category. Less dangerous drugs such as marijuana, cigarettes, caffeine, tobacco, etc. cause more damage to the user than any one else and most likely will not lead to violent acts. Some may help in administering violent ideas, but not in acting out violent acts. Based on the information I've gathered, I think that around 30% of youth violence in America are connected with drug use in some way. All and All I believe violence among kids is more of a mental health or house hold related issue rather than with drug use. I'm not promoting drugs or anything, I just don't think they are connected. In my opinion, I don't think it really matters whether or not drugs are legalized. No matter what happens, people will always be taking drugs. It's more of a personal decision than anything else, I mean there is no law stating you cannot cut yourself. But once someone is at the stage when he or she is endangering others and not themselves is when it becomes a real issue. The best way I believe drugs should be dealt with is the same as alcohol. If people want to hurt themselves, that's their problem. Social Issues

Environmental Ethics Essay Sample

Environmental Ethics Essay Sample Environmental Ethics Essay Our environment is one of the most important structures of the physical world that need to be valued and respected. This is because it provides essential elements to offer life. The Earth’s atmosphere is one of the most important structures that Mother Nature created because it offers a place for every organism to thrive. Human Beings need an atmosphere so that they can live in a certain period of time. We thrive by scouting natural resources that sustain our survival such as food. Our environment offers us shelter from any environmental hazards such as natural calamities that often strikes anywhere around the world on a regular basis. However, our environment is at risk for being abused by the humanity due to manmade hazards. Environmental ethics is associated with the existing law that mandates the society to respect our natural environment and preserve the society. The goal of promoting environmental ethics is to decrease the number of environmental violations that risks our surroundings from being damaged. Environmental laws and policies ensure that our environment is protected from any man-made hazards that attempt to destroy our physical environment. As a result, any violators are apprehended by the local and national government units with the cooperation of the law enforcement agencies. The reason behind is that violators are responsible for destroying our natural environment through pollution. Apprehensions can imprison perpetrators of environmental ethics violations because they are considered threats to the society. This is because there is a growing problem with regards to the competition between nature and a man-made settlement that are changing our physical environment that is observed on a ra pid scale. Pollution is the main cause of environmental hazards that disrespects the essence of environmental ethics. Major companies such as mining firms usually dump toxic waste to water ways and sewerage systems that contaminate rivers, streams, and oceans. Land pollution is commonly caused by humans who dump their waste anywhere, which clogs the canals. As a result, clogged canals are the most common scenario that increases risks of flooding in an area that are filled with numerous waste materials. When waste materials will flow through the rivers and reach open seas, it creates a risk to marine ecosystems, which kills fishes and other marine creatures. Vehicles that are fueled by petroleum products are one of the main causes of air pollution. Vehicles need gasoline or diesel in order to generate energy. However, the smoke emits reaches the atmosphere and saturating carbon particles that block the sun’s rays. Global warming is the result of violating environmental ethics such as pollution. This is a condition wherein it saturates carbon particles into the atmosphere. The heat cannot escape from the Earth’s atmosphere towards space because it is blocked by the carbon particles that generated a thin layer above the sky. Gradual increasing of temperature causes the sea levels to rise, causing stronger natural calamities such as intense tropical cyclones. Violating environmental ethics serves as a lesson to the population because it results in a catastrophic impact on our environment. One example is low lying islands across the world that are slowly swallowed by the rising seas. This is a consequence that is non-stoppable because the sea level continues to rise each year that threatens low lying areas around the world to sink in the future (Sutter Berlinger, 2015). Reference Sutter, John D. Berlinger, Joshua (2015).  Final draft of climate deal formally accepted in Paris.  CNN. Cable News Network, Turner Broadcasting System, Inc.

Lesson 11 - Course Project 1 Essay Example | Topics and Well Written Essays - 1000 words

Lesson 11 - Course Project 1 - Essay Example Atkins and Granger make liberal use of this budget-making technique when making sales and expense projections. Budgetary slacks alleviate the effects of deviations if they occur. A more shifty use of the technique is to make it easier for managers to achieve targets, especially where sales performance results in bonuses and appraisals (Stevens 1). Budgetary slacks in sales and expenditure projections can adversely affect the staff the projections relate. In the case of Atkins and Granger, altered projections can result in less motivation to achieve more in their areas of responsibility as they can alter the figures to give the impression that they are performing beyond the projections. On another note, if the two staff can alter the financial figures at will, then there is serious risk of the pair falsifying account figures to serve selfish interests (Stevens 1). The Institute of Management Accountants (IMA) requires its members behave ethically, and in ways that are responsible, honest, fair, and objective (IMA 1). IMA categorically opposes the use of confidential information for unethical and illegal motives. Overall, management accountants should cultivate restraint in situations that pose conflicting interests. IMA also requires that management accountants evade activities such as the budgetary slack that may jeopardize efficient execution of some activities. A budgetary slack presents amble opportunities for information asymmetry (Stevens 1). For instance, Granger cannot tell with certainty the actual sales figures because Atkins changes them before handing them over. On credibility, the IMA expects that management accountants disclose all relevant information that may influence the understanding, and use of the information (IMA 2). Modification of sales figures by Atkins adversely affects the ability by Granger to predict closing inventory levels, which is clearly unethical. In addition, Atkins

Reflection about a Book A Tale of Two Indians Essay

Reflection about a Book A Tale of Two Indians - Essay Example Having been born in India, he underwent different cultural experiences during his childhood that saw him through to his campus life. This section brings to the attention of the reader the rich family backgrounds of the author. After departing India when he was still young, his parents moved to England where he spent most of his childhood years. He undertook the British educational system in elementary education. After a pronounced stay in the United Kingdom, his family then moved again into the United States. Here is where his teenage life began. During his high school education coupled with college and university life, he underwent harsh realities in new environments. Consequently, he was caught up in great confusion, dilemma and inability to make further progress. This section, however, presents the challenges that face many people in life. Some of them become unwilling to continue with life while others, like the author continue to find the slightest implication of solution to con tinue surviving. On the same note, Patel continues to narrate on how the realities were difficult when a new education system does not provide the appropriate channel for success in educational life. Great confusions in addition to hardships in campus make it a great trial in life. After he was expelled from Duke University for cheating, he underwent desperation and, thus, almost succumbed to suicidal thoughts. At the moments of near-death, he recalled a small village in India where he used to make frequent visits as a child during his stay in India. He sought for a reconnection to the past. When he makes the visit to his country of origin, some big differences that include demographical, economical, social and political emerge. These events bring in a contrast of two generations separated miles apart and with different reaction tendencies. His worst scenarios involve his university education where he was considered unfit for long-term stay after allegations of exhibition of dishone sty in his studies. Although he remarkably instills that the American perception of immigrant Americans was not welcoming, his life in America was also not appealing. This view is, however, not reflective of conventional perception of American citizens. This, therefore, becomes a line of defense for his challenged life. Events that lead to a recall of the past. The author chronologically narrates about the events that lead the main character to make a decision to visit his ancestral home. After Patel faced so many challenges in his life (since this book is taken as a recount of the past) some of which he could not handle, depression crept in. Among the challenges included his expulsion from Duke University and continual solitude that resulted to reduced levels of motivation. After continual stress and depression, he experienced trivial life challenges that led him to a land of the lost. He became indulging and sunk into substance abuse. His decision to engage in drugs and alcoholism did not seem to make any situation better. Instead, things continued to worsen. After several failed attempts, his final thoughts of committing suicide almost convinced him to take his own life. Just before committing suicide, he recalled one of his close relatives back in India who as he remembers was tough and faced reality with stiffness. Memories convinced him that perhaps sharing a word with this old man would lead to better

Solenoid Operated Piston Pump Engineering Essay

Solenoid Operated Piston Pump Engineering Essay This project is aimed at analysing and designing a solenoid operated piston pump which is capable of delivering solution (this report assumes water) at a flow rate of 1 litre/min. However, the customer usage requires the flow rate to remain between 0.9 and 1.1 litre/min at an ambient pressure of about 1 bar. The operation mode of the piston pump is described below using the diagram: OscillPistonPump Fig 1.1 Solenoid Operated Piston Pump1 The solenoid coil (4) generates an electromagnetic field by the single wave diode rectified current flowing through the coil. Each current pulse moves the piston (5) against the pressure spring (3). This movement reduces the volume in the suction chamber causing an increase in pressure (P a 1/V), which opens the valve (6) in the piston, thereby allowing the liquid to run into the pressure side. When the current acting on the solenoid pulse is off, the pressure spring pushes back the piston toward the pressure side. The increase of pressure caused by the piston movement closes the piston valve (6) and the liquid flows through the valve (7) set in the pressure connection (8) and into the pressure pipe. The piston movement also simultaneously increases the volume in the suction chamber, thereby reducing the pressure below the chamber. The low pressure in the suction chamber opens the valve (2) set in the suction connection (1), and the liquid is sucked into the pump and the cycle starts again. The piston size and the length of its displacement define the flow rate. The pump will run without damage when the liquid flow is stopped momentarily1. This design concentrated on the piston, suction chamber and pressure springs design. Although references were made to the valves and solenoid force, engineering analysis were not carried out on them. CHAPTER 2 INITIAL ENGINEERING DESIGN ANALYSIS This section considered the engineering analysis of the operation of the piston pump to achieve the require specifications. The given specifications are; Flow rate Q = 1 Lit/min Frequency F = 60 cycles/sec Ambient Pressure = 1 bar Using the above specifications, the length of stroke of the piston, which is also termed as the â€Å"Swept Volume†, can be calculated using the relation below: Q = Volumetime=Volume Ãâ€"frequency = Ï€ d2 L4 Ãâ€"f ∠´L= 4QÏ€d2f Where: Q = Flow Rate =1 lit/min= 1.667 Ãâ€"104 mm3/sec f = Frequency (cycles/sec) L = Length of stroke/Swept volume (mm) d = Diameter of piston/suction chamber (mm) The diameter was varied from 1 to 20 mm and the corresponding lengths of stroke were obtained at different frequencies of 40, 45, 50, 55 and 60 cycles/sec. The results obtained were plotted (See appendix 1). After careful look, the frequency at 40 cycle/sec, so subsequent calculations would be based on this. It was also noticed that reasonable pair of dimensions of the diameter and length occurred around the diameters 5-10mm, therefore subsequent calculations were based on this range. 2.1 LOAD ANALYSIS The load analysis was carried out on each component designed as indicated below: A. Piston: The load analysis on the piston was done by isolating the piston and analysing the forces acting it. The different forces acting on the piston are as shown below: Force on piston causing acceleration Magnetic force from solenoid coil Resultant spring force Kinematic frictional force Gravitational force Resultant hydraulic force (including assumed viscous effect) This is assuming that atomic, initial static frictional force and temperature effects are negligible. The force analyses were carried out considering three different cases under which the pump operation can undergo. The intake and ejection strokes were also analysed separately to reduce complications. The difference between the intake and ejection stroke is that, the magnetic force from the solenoid is zero during ejection, because the solenoid is off: Case I: This is when the piston pump is used horizontally, that is, it is used to pump fluid on the same datum. This means that the gravitational effect and the height difference in the hydraulic force will be zero. The relationship between the forces will therefore be: Intake stroke: Force causing motion = Force from solenoid Resultant spring force Resultant hydraulic force Frictional force Ejection stroke: Force causing motion = Resultant spring force Resultant hydraulic force Frictional force Case II: This considered the case when the pump is used to transfer fluid from a higher level to a lower level. This means that the gravitational effect will favour the direction of flow therefore reducing the force needed to drive the piston. The relationship between the forces will therefore be: Intake stroke: Force causing motion = Force from solenoid Resultant spring force Resultant hydraulic force Frictional force Gravitational force Ejection stroke: Force causing motion = Resultant spring force Resultant hydraulic force Frictional force + Gravitational force Case III: This considered the case when the piston pump is used to deliver fluid from a lower level to a higher level. The difference between this case and case II is in the gravitational effect and the datum difference in the hydraulic effect. The design load analysis was done under this circumstance because pumps are usually used for this particular purpose. Even with this design concept, the pump can still be used for other cases, but it might deliver fluid at a higher flow rate, which could still be in the boundaries of the given tolerance of the flow rate. The relationship between the forces will therefore be: Intake stroke: Force causing motion = Force from solenoid Resultant spring force Resultant hydraulic force Frictional force + Gravitational force Ejection stroke: Force causing motion = Resultant spring force Resultant hydraulic force Frictional force Gravitational force. The different forces were calculated as follows using the free body diagram of the piston shown below: Figure 2.1 Boundary conditions of intake and ejection strokes Force from solenoid coil= Fs Force on piston causing motion = Mpa Where Mp = mass of piston kg and a = acceleration of piston (mm/s2) Mp= Ï  Ãâ€"V Ï  = Density of material (Stainless steel) =8Ãâ€"10-6 (kg/mm3) V=Volume of fluid displced in one stroke mm3= Q Ãâ€"t= Qf where f=45 cycles/sec=90 strokes/sec (2 strokes=1 cycle) Mp= Ï  Ãâ€" Qf=8Ãâ€"10-6 Ãâ€" 1.667 Ãâ€"10490=1.482Ãâ€"10-3 From law of motion; v2= u2+ 2aS u = 0 ∠´a=v22S Also v= St= S Ãâ€"f v=Velocity (mm/s) and S= L=Length of stroke (mm) ∠´a=L Ãâ€"f22L= L Ãâ€" f22= L Ãâ€" 9022 The length was varied from 5 to 10 mm, and different accelerations were obtained (See appendix 2). Resultant spring force = K2∆x- K1∆x= ∆xK2- K1= ∆x∆K Where K1 and K2=Stiffness of springs 1 and 2 respectively (N/mm) ∆x=L=Stoke length (mm) Kinematic frictional force = ÃŽ ¼kÃâ€"N= ÃŽ ¼kÃâ€"Mpg Where ÃŽ ¼k=Coefficient of kinematic friction N=Normal force= Mpg g=acceleration due to gravity=9810 mm/s2 Gravitational force = Mpg Hydraulic force = Total Change in Pressure ∆P (N/mm2)Surface Area of Piston A (mm2) From Bernoulllis equation   P1Ï g+ V122g+ Z1= P2Ï g+ V222g+ Z2 ∆P= P1-P2=Ï V22-V122+ ∆ZÏ g Q= A1V1= A2V2 ,   then V2= QA2= A1V1A2 and V1= QA1 ∆P= Ï A1V1A22-V122+ ∆ZÏ g= V12Ï 2 A1A22- 1+ ∆ZÏ g ∆P= Ï  Q22A12A1A22- 1+ ∆ZÏ g Where Q= Flow rate (mm3/s) , Ï  =density of water =1Ãâ€"10-6 (kg/mm3) A1and A2=Area mm2   and V1 and V2=Velocity (m/s) ∆Z=L=Length of Stroke mm Including the discharge coefficient C = 0.98 to account for viscous effect, ∆P therefore becomes: ∆P= Ï  Q22C2A12A1A22- 1+ LÏ g ∠´ Hydraulic force = Ï  Q22C2A12A1A22- 1+ LÏ gSurface Area of Piston A mm2 = Ï  Q22C2A12A1A22- 1+ LÏ gA2- A1 The forces were algebraically added according the ejection stroke equation developed above (case III) to obtain ?K at different diameter of pistons, fixing inner diameter of Piston D2 (corresponding to A2) = 0.5, 1, 1.5, 2 and 2.5mm (See appendix 3). Force causing motion = Resultant spring force Resultant hydraulic force Frictional force Gravitational force. Mpa= L ∆K- Ï  Q22C2A12A1A22- 1+ LÏ gA2- A1- ÃŽ ¼kMpg- Mpg ∆K= 1LMpa+ ÃŽ ¼kg+g+ Ï  Q22C2A12A1A22- 1+ LÏ gA2- A1 The hydraulic effect is due to the fluid forced out from the suction chamber into the outlet. Therefore the A1 and A2 will be the area of the piston and the outlet, corresponding to diameters D1 and D2 respectively. Also the outlet diameter was assumed to be equal to the inner diameter of the piston. The results obtained for difference in stiffness ?K above, were used to obtain the force from solenoid coil Fs using the injection stroke equation above. Also different diameter of piston were used while varying the inner diameter of piston D2 (corresponding to A2) = 0.5, 1, 1.5, 2 and 2.5mm (See appendix 4). Considering the intake stroke equation for case III: Force causing motion = Force from solenoid Resultant spring force Resultant hydraulic force Frictional force + Gravitational force Mpa= Fs-L∆K- Ï  Q22C2A12A1A22- 1+ LÏ gA1- ÃŽ ¼kMpg+ Mpg Fs= Mpa+ ÃŽ ¼kg-g+L∆K+ Ï  Q22C2A12A1A22- 1+ LÏ g A1 The hydraulic effect is due to the change in pressure as the fluid passes through the piston, because of the reduction in area. Therefore the A1 and A2 will be the area of the piston outer and inner diameter, corresponding to diameters D1 and D2 respectively. B. Pressure Springs: The load analysis of the spring was also done by isolating the spring and analysing the forces acting it. Considering the ejection stroke of upper spring (spring 1), the different forces acting on the spring are as shown below: Force on piston causing acceleration Spring force Resultant hydraulic force (including assumed viscous effect) This is assuming that the frictional force on spring is negligible because the surface area contacting the wall is small. Force causing motion = Spring force + Resultant hydraulic force Mpa= LÃâ€"K1+ Ï  Q22C2A12A1A22- 1+ LÏ g A1 K1=1LMpa- Ï  Q22C2A12A1A22- 1+ LÏ g A1 ∠´K2=K1+∆K Where Force on springs Fsk=KÃâ€"Length of stroke The values of stiffness of springs 1 and 2 were calculated using the relationships above at different outer and inner diameters of the piston. The graphs were plotted to see the variations (See appendix 5 and 6). C. Inlet Valve and Spring: Considering also the inlet valves and analysing the forces acting it, the injection stroke is caused by an increase in volume of the suction chamber, causing a corresponding decrease in pressure. Therefore the different forces acting on the inlet valve are given below: Inlet spring force at compression Resultant hydraulic force (including assumed viscous effect) This is assuming that the frictional force and gravitational force on the valve is negligible because the valve is light. Resultant Pressure Change= ?P From Gas Law: P1V1= P2V2 P1 and P2 are the initial and final pressures of both the inlet and suction chamber respectively (N/mm2). The initial pressure P1 is assumed to be equal to the external pressure which is given to be equal to the atmospheric pressure Pa = 1 bar = 0.1 N/mm2. That is why fluid is not flowing because there is no pressure difference, or P1 was higher than Pa P2= P1V1V2= PaV1V2 where V2=V1+Vs and Vs=Swept Volume per stoke Vs=Flow rateFrequency in stroke/sec=1.667Ãâ€"10490 =185.22 mm2/stroke P2= P1V1V1+Vs ∆P1=Change in pressure due to swept volume= Pa-P2 ∆P1=Pa-PaV1V1+Vs=Pa V1+Vs-PaV1 V1+Vs=PaV1-PaV1+PaVsV1+Vs=PaVsV1+Vs Where V1 = VT and it is the total volume of the inlet spring area, suction chamber and the inner space of the piston. ∆P2=Pressure Change due to area changes ∆P2=Ï  Q22C2A12A1A22- 1+ LÏ g The above pressure change is the sum of the pressure changes from the inlet through suction chamber and into pistons inner diameter. This is negligible because the pressure drops as it enters the suction chamber and increases as it enters the inner diameter of piston, thereby almost cancelling out. ∆P=∆P1=PaVsVT+Vs Hydraulic force=spring force at compression ∆P1A3=PaVsA3VT+Vs= K3x3 PaVs=K3x3A3VT+ K3x3A3Vs VT=PaVs- K3x3A3VsK3x3A3 Where A3=Inlet area mm2, K3=Inlet Spring Stiffness (N/mm) and x3=Spring movement=Valve lifting mm The values the total internal volume VT was obtained at different values of the diameter of the inlet D3 (corresponding to A3). The value of the spring force K3x3 was varied from 0.01 to 0.05 N and the variations were plotted to see an appropriate one (See appendix 7). 2.2 Component Design and Selection The component design has been carried out along with the load analysis shown above. The desired dimensions for different components were then selected after a careful study and analysis of the graphs plotted. The dimensions were selected based on those that satisfy the required specifications, reasonably able to be manufactured and can be selected from the manufacturers catalogue as in the case of the springs2. Below are the component dimensions: Solenoid: Solenoid Frequency: 45cycles/sec = 90 strokes/sec Force from solenoid coil: 108.8N Length of stroke: 7.367 mm Piston: Piston outer diameter: 8 mm Piston inner diameter: 2 mm Springs: Pressure spring 1 rate = 5.771 N/mm Force on spring 1 = Rate * length of stroke = 5.771 * 7.367 = 42.515 N Pressure spring 2 rate = 14.683 N/mm Force on spring 1 = Rate * length of stroke = 14.683 * 7.367 = 108.17 N From the above calculations and estimated values of the spring rates, the most accurate spring chosen from the compression spring catalogue are (see appendix 8 and 9): Spring 1: C6609150 Wire diameter: 1.02 mm Outer Diameter: 7.62 mm Free length: 15.88 mm Rate: 5.81 N/mm Spring 2: D22110 Wire diameter: 1.25 mm Outer Diameter: 7.55mm Free length: 17mm Rate: 15.03 N/mm Inlet: Inlet spring stiffness = 0.02 N/mm Inlet spring length = 9.804 mm Inlet diameter = 1.78 mm 2.3 Stress Analysis The stress analysis was carried out on just two components as shown below. This was because these are the two components whose failure affects the pump operation most. A. Piston: The two stresses acting on the piston are normal and shear stresses which is given as. Stress (N/mm2) sij= Force (N)Area (mm2) The notation is to differentiate between the direction and plane of action, where the first digit represents the plane of action and the second digit represents the direction of force. When the notations are different, it signifies shear stress and when the notations are the same it means normal stress. The force on the piston varies as the piston goes through the cycle, therefore the different forces and principal stresses were calculated as the spring compresses and stretches. This was shown in appendix 10 and 11, but the calculations of the maximum and minimum principal stresses at the springs peak are shown below. The principal stresses were calculated because they are the cause of fracture in a component3. Considering the piston and spring 1: Fig 2.2: Stresses acting on piston from spring 1 and wall3 s11= 0 because there is no horizontal force in that direction s12= Force from SolenoidSurface area of piston= Fsp Do Lp= 108.8pÃâ€"8Ãâ€"15=0.2886 N/mm2 Where D0=Outer diameter of piston mm, Lp=Length of Piston (mm) s22= Force from spring 1Outer Area-Inner Area= K1Lp4 Do2- Di2 s22=5.771 Ãâ€"7.367p4 82- 22= 42.51547.1239=0.9022 N/mm2 s21= 0 because there is no horizontal force in that direction Considering the piston and spring 2: s11= 0 because there is no horizontal force in that direction s12= Force from SolenoidSurface area of piston= Fsp Do Lp= 108.8pÃâ€"8Ãâ€"15=0.2886 N/mm2 Where D0=Outer diameter of piston mm, Lp=Length of Piston (mm) s22= Force from spring 2Outer Area-Inner Area= K2Lp4 Do2- Di2 s22=14.638 Ãâ€"7.367p4 82- 22= 107.838147.1239=2.2884 N/mm2 s21= 0 because there is no horizontal force in that direction The total principal stress which is the usual cause of fracture was calculated using the total normal stresses from the springs and the shear stress from solenoid. Total shear stresses: Ts12=s12 from Spring 1+ s12 from Sprig 2=0.2886+0.2886= 0.5772 Total normal stresses: Ts22=s22 from Spring 1+ s22 from Sprig 2=0.9022+2.2954= 3.1976 Therefore the principal stresses: s11s22- s(s11+s22)+s2-s122=0 0Ãâ€"3.1976- s(0+3.1976)+s2-0.57722=0 s2-3.1976s-0.3331=0 Principal stresses; smin=-0.101 N/mm2, smax=3.2986 N/mm2 B. Pressure Springs: The major stress acting on the spring is shear stress acting on the coils. The force and consequentially the shear stress on the springs vary as the piston deflection (i.e. length of stroke) increases and decreases. The various forces and shear stresses were calculated and the graph plotted (see appendix 12). But the calculation of the maximum shear stress, which occurs at the full deflection is shown below4: Fig 2.4: Force acting on spring4 Shear stress tmax= 8FDWpd3 Where F=Force on spring N D=Mean outer diameter of spring mm d=diameter of spring coil mm W = Wahl Correction Factor which accounts for shear stress resulting from the springs curvature W=4C-14C-4+0.615C C=Dd Considering Spring 1 Fmax= K1Ãâ€"Length of stroke=5.771Ãâ€"7.367=42.515 N/mm2 D=7.62 mm and d=1.02 mm ?C=Dd= 7.621.02=7.4705 W=4C-14C-4+0.615C= 4Ãâ€"7.4705-14Ãâ€"7.4705-4+0.6157.4705=1.1982 tmax= 8FmaxDWpd3= 8Ãâ€"42.515 Ãâ€"7.62Ãâ€"1.1982pÃâ€"1.023=931.113 N/mm2 Considering Spring 2 Fmax= K1Ãâ€"Length of stroke=14.638Ãâ€"7.367=108.17 N/mm2 D=7.55 mm and d=1.25 mm ?C=Dd= 7.551.25=6.04 W=4C-14C-4+0.615C= 4Ãâ€"6.04-14Ãâ€"6.04-4+0.6156.04=1.2506 tmax= 8FmaxDWpd3= 8Ãâ€"108.17 Ãâ€"7.55Ãâ€"1.2506pÃâ€"1.253=1331.119 N/mm2 CHAPTER 3 INITIAL MANUFACTURING DESIGN ANALYSIS 3.1 Dimensions The dimensions of all the main components; piston, springs, cylinder and valves had been obtained from the calculations and graphical analysis made above. However, the detailed dimensions of all components namely; pump body (left and right side), cylinder and liners, piston, springs and valves are shown in the CAD drawing in appendix 13. 3.2 Tolerances Tolerance for Stroke Length The statistical tolerance of the stoke length was calculated using integral method, which is much more effective than an additional tolerance. Given the tolerance of the flow rate as  ± 0.1litres/min, the tolerance of the frequency was assumed to be  ± 5 cycles/sec under normal distribution condition. The tolerance of the stroke length was calculated as follows: Standard deviation s=Tolerance3 Ãâ€"Cp where Cp=process capability index In general manufacturing industry, a process capability index (Cp) of 1.33is considered acceptable. Therefore Cp Flow rateQ=1  ±0.1 lit/min= 1.667 Ãâ€"104  ±1.667 Ãâ€"103mm3/sec   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   ÏÆ'Q=3.33 Ãâ€"1033 Ãâ€"1.33=8.356 Ãâ€"102 Frequency F= 45  ±5 cycles/sec (Assuming a Normal distributed variable)   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   ÏÆ'f=103 Ãâ€"1.33=2.506 Therefore the flow rate and frequency could be written as; Q ~ N 1.667 Ãâ€"104 , 8.356 Ãâ€"102 mm3/sec f ~ N 45 , 2.506 cycles/sec Q = Volumetime=Volume Ãâ€"frequency = Ï€ d2 L4 Ãâ€"f ∠´L= 4QÏ€d2f Using differential tolerance: ÏÆ'∅2= i=1n∂∅∂xi2 ÏÆ'xi2 ÏÆ'L2= ∂L∂Q2ÏÆ'Q2+ ∂L∂f2ÏÆ'f2+ ∂L∂d22ÏÆ'd2 ÏÆ'L2= 4Ï€ 1ÃŽ ¼d2 Ãâ€"ÃŽ ¼f2ÏÆ'Q2+ ÃŽ ¼QÃŽ ¼d2 Ãâ€"ÃŽ ¼f22ÏÆ'f2+ ÃŽ ¼QÃŽ ¼d3 Ãâ€"ÃŽ ¼f2ÏÆ'd2 Ãâ€"2 ∠´Tolerance=ÏÆ'3 Ãâ€"Cp The standard deviations and tolerances of the stoke length were calculated using the above equations, while varying the diameter from 1 to 20 mm, and the results were plotted out (see appendix 14). Tolerance for Piston Principal Stress Assuming a normally distributed around the maximum principal stress acting on the piston, the standard deviation and the tolerance of the maximum principal stress was calculated using the load distribution obtained in appendix 11. ∠´3ÏÆ'=3.2918-0.5772=2.7146 Tolerance=CpÃâ€"3ÏÆ'=1.33Ãâ€"2.7146=3.6104 N/mm2 Upper and lower limit=3.61042= ± 1.8052 N/mm2 Tolerance for Springs Shear Stress Also assuming a normally distributed around the maximum shear stress acting on the springs, the standard deviation and the tolerance of the maximum shear stress was calculated using the load distribution obtained in appendix 12. For spring 1: ∠´3ÏÆ'=931.113-0=931.113 Tolerance=CpÃâ€"3ÏÆ'=1.33Ãâ€"931.113=1238.38 N/mm2 Upper and lower limit=1238.382= ± 619.19 N/mm2 For spring 2: ∠´3ÏÆ'=1331.119-0=1331.119 Tolerance=CpÃâ€"3ÏÆ'=1.33Ãâ€"1331.119=1770.39 N/mm2 Upper and lower limit=1770.392= ± 885.195 N/mm2 3.3 Fits The components that are fitted into the cylinder, namely; cylinder liner, piston springs 1 and 2 are almost of equal diameter. But because of the consideration of the fits and limits to give some allowance a transition fit was chosen from â€Å"Data Sheet 4500A British Standard selected ISO Fits-Hole Basis†. Since it fell in between the nominal size of 0 6 mm, the transition fit selected was H700.015 for the hole and k60-0.009 for the shaft5. 3.4 Material Selection Piston and Cylinder The piston and the cylinder are to be made of stainless steel grade 431. This is due to the prevention of fracture which could be caused by principal stress. From the maximum principal stress obtained for the piston above (3.2986 N/mm2 = 3.2986 MPa), it is sure that the material which has a yield strength of 655 MPa will be able to prevent failure. Also the other reason for choosing this material is because of its high resistance to corrosion6. Since the piston and cylinder interacts with the fluid, which increases the tendency for corrosion to occur, it is quite safe to use a highly corrosion resistance material like this. It is also very easily machined in annealed condition. The properties of the stainless steel grade 431are shown in appendix 156. Springs The springs are to be made of stainless steel grade 316. This is also due to the strength of the grade in preventing fracture, breakage and buckling of the spring due to the shear stress acting on it. From the maximum shear stress calculated above (1331.119 N/mm2 = 1.331 GPa), it is sure that this grade of stainless steel with an elastic modulus of 193 GPa will be able to withstand the compression. The material is also highly corrosion resistant and relatively easy to machine. The other properties of the stainless steel grade 316 are shown in appendix 156. Valves The valves are to be made of polytetrafluoroethylene PTFE, which is a thermoplastic. This was chosen because the material has to be light and can easily float. Also, it has very low coefficient of friction, which reduces the fluid drag force and wears on the piston and spring. 3.5 Surface Finish The surface finishing chosen for the manufacturing of the parts was to be 0.8  µm Ra. This is to reduce friction and rate of wear, because there are lots of parts moving against each other. The grinding process requires a very great accuracy because it is a relatively delicate manufacturing process. 3.6 Geometric Tolerance In obtaining the tolerance of the components, since algebraic addition of tolerances is very unrealistic and will not be efficient, the tolerances of components that fit into each other were taken from the â€Å"Data Sheet 4500A British Standard selected ISO Fits-Hole Basis†5. These are show below S/No Parts Dimensions (mm) Tolerances (mm) Drawings 1 Cylinder 11.00 + 0.015 2 Cylinder liner 8.00 0.009 3 Piston 2.00 0.006 4 Spring 1 17.00  ± 0.0015 3.7 Process Selection The manufacturing processes of the various parts of the pump will be very important aspects of the design.The parts to be manufactured are pump body, cylinder liners and piston. It will take a great deal of accuracy in carrying out the process, because the geometry of the parts is very delicate. Any wrong dimension will affect the output or operation of the pump. There are three steps in manufacturing the components mentioned above. Firstly, all the components would be manufactured by casting, which would probably not give the accurate dimensions. Then a turning/boring process can then be carried out, using a CNC or lathe machines, to achieve better dimension. The last process is the surface finish, which gives a smoother and precise dimension. It is relatively easier to manufacture the components by this method because of the intricacies of the geometry and dimensions, and also the materials chosen are easily machined. The manufacturing process of the springs would not be considered in this report because they are provided by suppliers. CHAPTER 4 DESIGN OPTIMISATION 4.1 Component Manufacturing Risk Assessment Component Name Pump Body (Left Right Side) Calculation of qm Drawing number 001 mp = 1 Ãâ€" 1.6 = 1.6 gp = 1.7 Ãâ€" 1 Ãâ€" 1 Ãâ€" 1 Ãâ€" 1.1 Ãâ€" 1.1 = 2.057 Ajustable tol= Design tolmpÃâ€"gp = + 0.0151.6 Ãâ€"2.057=+0.00455 tp = 1.7Ãâ€"1 = 1.7 sp = 1 Ãâ€" 1.3 = 1.3 qm = 1.7 Ãâ€" 1.3 = 2.21 Manufacturing variability risk, qm = 2.21 Material 431 Stainless Steel Manufacturing Process Turning/Boring Characteristic Description Holes at centre to edge Characteristic Dimension 8 mm Design Tolerance + 0.015 Surface Roughness 0.8 µm Ra Component Name Piston Calculation of qm Drawing number 005 mp = 1 Ãâ€" 1.6 = 1.6 gp = 1 Ãâ€" 1 Ãâ€" 1 Ãâ€" 1 Ãâ€" 1 Ãâ€" 1.1 = 1.1 Ajustable tol= Design tolmpÃâ€"gp = 0.0061.6 Ãâ€"1.1=0.0034 tp = 1.7Ãâ€"1 = 1.7 sp = 1 Ãâ€" 1 = 1 qm = 1.7 Ãâ€" 1 = 1.7 Manufacturing variability risk, qm =1.7 Material 431 Stainless Steel Manufacturing Process Turning/Boring Characteristic Description Holes at centre to edge Characteristic Dimension 2 mm Design Tolerance 0.002, -0.008 Surface Roughness 0.8 µm Ra  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The values of the component manufacturing risk analysis obtained above are considerably with a low risk. This shows that the processes chosen for the manufacturing of the components are acceptable. 4.2 Failure Mode and Effects Analysis (FMEA) The failure mode and effects analysis (FMEA) is an analytical technique performed to ensure that all possible failure modes of the piston pump have being identified and address. Below are the predicted failure modes of each components of the piston pump, the caused, effects and the suggested solutions: It can be seen from the FMEA above that the spring breakage has the greatest severity, but the wear on all the components has the greatest risk priority number. This is because wear would be experience by the customer over time of use which made the risk priority number very high. Therefore, while desig