Saturday, April 25, 2020

When Quality Control Gets in the Way of Quality free essay sample

Total Quality Management (TQM) is a comprehensive and structured approach to organizational management that seeks to improve the quality of products and services through ongoing refinements in response to continuous feedback. TQM requirements may be defined separately for a particular organization or may be in adherence to established standards, such as the International Organization for Standardizations ISO 9000 series. TQM can be applied to any type of organization; it originated in the manufacturing sector and has since been adapted for use in almost every type of organization imaginable, including schools, highway maintenance, hotel management, and churches. As a current focus of e-business, TQM is based on quality management from the customers point of view. Four sequential categories TQM processes are divided into four sequential categories: plan, do, check, and act (the PDCA cycle). In the planning phase, people define the problem to be addressed, collect relevant data, and ascertain the problems root cause; †¢in the doing phase, people develop and implement a solution, and decide upon a measurement to gauge its effectiveness; †¢in the checking phase, people confirm the results through before-and-after data comparison; †¢in the acting phase, people document their results, inform others about process changes, and make recommendations for the problem to be addressed in the next PD CA cycle. We will write a custom essay sample on When Quality Control Gets in the Way of Quality or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page THE TOPIC MEANS: When there is an over-emphasis or over-doing in the process of quality control, it will narrow the path towards quality of the product or service concerned. Statistical control Many organizations use statistical process control to bring the organization to Six Sigma levels of quality, in other words, so that the likelihood of an unexpected failure is confined to six standard deviations on the normal distribution. This probability is less than four one-millionths. Items controlled often include clerical tasks such as order-entry as well as conventional manufacturing tasks. Traditional statistical process controls in manufacturing operations usually proceed by randomly sampling and testing a fraction of the output. Variances of critical tolerances are continuously tracked, and manufacturing processes are corrected before bad parts can be produced. Company quality During the 1980s, the concept of â€Å"company quality† with the focus on management and people came to the fore. It was realised that, if all departments approached quality with an open mind, success was possible if the management led the quality improvement process. The company-wide quality approach places an emphasis on three aspects :- 1. Elements such as controls, job management, adequate processes, performance and integrity criteria and identification of records 2. Competence such as knowledge, skills, experience, qualifications 3. Soft elements, such as personnel integrity, confidence, organisational culture, motivation, team spirit and quality relationships. The quality of the outputs is at risk if any of these three aspects are deficient in any way. The approach to quality management given here is therefore not limited to the manufacturing theatre only but can be applied to any business activity: †¢Design work †¢Administrative services †¢Consulting †¢Banking †¢Insurance †¢Computer software †¢Retailing †¢Transportation It comprises a quality improvement process, which is generic in the sense it can be applied to any of these activities and it establishes a behaviour pattern, which supports the achievement of quality. This in turn is supported by quality management practices which can include a number of business systems and which are usually specific to the activities of the business unit concerned. In manufacturing and construction activities, these business practices can be equated to the models for quality assurance defined by the International Standards contained in the ISO 9000 series and the specified Specifications for quality systems. Still, in the system of Company Quality, the work being carried out was shop floor inspection which did not control the major quality problems. This led to quality assurance or total quality control, which has come into being recently. Total quality control Total Quality Control is the most necessary inspection control of all in cases where, despite statistical quality control techniques or quality improvements implemented, sales decrease. The major problem which leads to a decrease in sales was that the specifications did not include the most important factor, â€Å"What the customer required†. The major characteristics, ignored during the search to improve manufacture and overall business performance were: †¢Reliability Maintainability †¢Safety As the most important factor had been ignored, a few refinements had to be introduced: 1. Marketing had to carry out their work properly and define the customer’s specifications. 2. Specifications had to be defined to conform to these requirements. 3. Conformance to specifications i. e. drawings, standards and other relevant documents, were introduced during manufacturing, planning and control. 4. Management had to confirm all operators are equal to the work imposed on them and holidays, celebrations and disputes did not affect any of the quality levels. . Inspections and tests were carried out, and all components and materials, bought in or otherwise, conformed to the specifications, and the measuring equipment was accurate, this is the responsibility of the QA/QC department. 6. Any complaints received from the customers were satisfactorily dealt with in a timely manner. 7. Feedback from the user/customer is used to review designs. 8. Consistent data recording and assessment and documentation integrity. 9. Product and/or process change management and notification. If the original specification does not reflect the correct quality requirements, quality cannot be inspected or manufactured into the product. For instance, all parameters for a pressure vessel should include not only the material and dimensions but operating, environmental, safety, reliability and maintainability requirements. To conclude, the above forms the basis from which the philosophy of Quality Assurance has evolved, and the achievement of quality or the â€Å"fitness-for-purpose† is â€Å"Quality Awareness† throughout the company. †¢ QUALITY CONTROL CHARTS In all production processes, we need to monitor the extent to which our products meet specifications. In the most general terms, there are two enemies of product quality: (1) deviations from target specifications, and (2) excessive variability around target specifications. During the earlier stages of developing the production process, designed experiments are often used to optimize these two quality characteristics; the methods provided in Quality Control are on-line or in-process quality control procedures to monitor an on-going production process. General Approach The general approach to on-line quality control is straightforward: We simply extract samples of a certain size from the ongoing production process. We then produce line charts of the variability in those samples, and consider their closeness to target specifications. If a trend emerges in those lines, or if samples fall outside pre-specified limits, then we declare the process to be out of control and take action to find the cause of the problem. These types of charts are sometimes also referred to as Shewhart control charts (named after W. A. Shewhart who is generally credited as being the first to introduce these methods). Interpreting the chart: The most standard display actually contains two charts (and two histograms); one is called an X-bar chart, the other is called an R chart. In both line charts, the horizontal axis represents the different samples; the vertical axis for the X-bar chart represents the means for the characteristic of interest; the vertical axis for the R chart represents the ranges. For example, suppose we wanted to control the diameter of piston rings that we are producing. The center line in the X-bar chart would represent the desired standard size (e. g. diameter in millimeters) of the rings, while the center line in the R chart would represent the acceptable (within-specification) range of the rings within samples; thus, this latter chart is a chart of the variability of the process (the larger the variability, the larger the range). In addition to the center line, a typical chart includes two additional horizontal lines to represent the upper and lower control limits (UCL, L CL, respectively); we will return to those lines shortly. Typically, the individual points in the chart, representing the samples, are connected by a line. If this line moves outside the upper or lower control limits or exhibits systematic patterns across consecutive samples, then a quality problem may potentially exist. Establishing Control Limits Even though one could arbitrarily determine when to declare a process out of control (that is, outside the UCL-LCL range), it is common practice to apply statistical principles to do so. Elementary Concepts discusses the concept of the sampling distribution, and the characteristics of the normal distribution. The method for constructing the upper and lower control limits is a straightforward application of the principles described there. The general principle for establishing control limits applies to all control charts. After deciding on the characteristic we want to control, for example, the standard deviation, we estimate the expected variability of the respective characteristic in samples of the size we are about to take. Those estimates are then used to establish the control limits on the chart. COMMON TYPES OF CHARTS The types of charts are often classified according to the type of quality characteristic that they are supposed to monitor: there are quality control charts for variables and control charts for attributes. Specifically, the following charts are commonly constructed for controlling variables: †¢X-bar chart. In this chart the sample means are plotted in order to control the mean value of a variable (e. g. , size of piston rings, strength of materials, etc. ). †¢R chart. In this chart, the sample ranges are plotted in order to control the variability of a variable. †¢S chart. In this chart, the sample standard deviations are plotted in order to control the variability of a variable. †¢S**2 chart. In this chart, the sample variances are plotted in order to control the variability of a variable. For controlling quality characteristics that represent attributes of the product, the following charts are commonly constructed: †¢C chart. In this chart (see example below), we plot the number of defectives (per batch, per day, per machine, per 100 feet of pipe, etc. ). This chart assumes that defects of the quality attribute are rare, and the control limits in this chart are computed based on the Poisson distribution (distribution of rare events). †¢U chart. In this chart we plot the rate of defectives, that is, the number of defectives divided by the number of units inspected (the n; e. . , feet of pipe, number of batches). Unlike the C chart, this chart does not require a constant number of units, and it can be used, for example, when the batches (samples) are of different sizes. †¢Np chart. In this chart, we plot the number of defectives (per batch, per day, per machine) as in the C chart. However, the control limits in this chart are not based on the distribution of rare events, but rather on the binomial distribution. Therefore, this chart should be used if the occurrence of defectives is not rare (e. g. , they occur in more than 5% of the units inspected). For example, we may use this chart to control the number of units produced with minor flaws. †¢P chart. In this chart, we plot the percent of defectives (per batch, per day, per machine, etc. ) as in the U chart. However, the control limits in this chart are not based on the distribution of rare events but rather on the binomial distribution (of proportions). Therefore, this chart is most applicable to situations where the occurrence of defectives is not rare (e. g. , we expect the percent of defectives to be more than 5% of the total number of units produced). All of these charts can be adapted for short production runs (short run charts), and for multiple process streams. Out-Of-Control Process: Runs Tests As mentioned earlier in the introduction, when a sample point (e. g. , mean in an X-bar chart) falls outside the control lines, one has reason to believe that the process may no longer be in control. In addition, one should look for systematic patterns of points (e. g. , means) across samples, because such patterns may indicate that the process average has shifted. These tests are also sometimes referred to as ATT runs rules or tests for special causes. The term special or assignable causes as opposed to chance or common causes was used by Shewhart to distinguish between a process that is in control, with variation due to random (chance) causes only, from a process that is out of control, with variation that is due to some non-chance or special (assignable) factors. As the sigma control limits discussed earlier, the runs rules are based on statistical reasoning. For example, the probability of any sample mean in an X-bar control chart falling above the center line is equal to 0. 5, provided that: (1) the process is in control (i. e. that the center line value is equal to the population mean), (2) consecutive sample means are independent (i. e. , not auto-correlated), and (3) the distribution of means follows the normal distribution. Simply stated, under those conditions there is a 50-50 chance that a mean will fall above or below the center line. Thus, the probability that two consecutive means will fall above the center line is equ al to 0. 5 times 0. 5 = 0. 25. Accordingly, the probability that 9 consecutive samples (or a run of 9 samples) will fall on the same side of the center line is equal to 0. 5**9 = . 0195. Note that this is approximately the probability with which a sample mean can be expected to fall outside the 3- times sigma limits (given the normal distribution, and a process in control). Therefore, one could look for 9 consecutive sample means on the same side of the center line as another indication of an out-of-control condition. Refer to Duncan (1974) for details concerning the statistical interpretation of the other (more complex) tests. Zone A, B, C. Customarily, to define the runs tests, the area above and below the chart center line is divided into three zones. By default, Zone A is defined as the area between 2 and 3 times sigma above and below the center line; Zone B is defined as the area between 1 and 2 times sigma, and Zone C is defined as the area between the center line and 1 times sigma. Process Capability Indices For variable control charts, it is often desired to include so-called process capability indices in the summary graph. In short, process capability indices express (as a ratio) the proportion of parts or items produced by the current process that fall within user-specified limits (e. g. , engineering tolerances). For example, the so-called Cp index is computed as: Cp = (USL-LSL)/(6*sigma) where sigma is the estimated process standard deviation, and USL and LSL are the upper and lower specification (engineering) limits, respectively. If the distribution of the respective quality characteristic or variable (e. g. , size of piston rings) is normal, and the process is perfectly centered (i. e. , the mean is equal to the design center), then this index can be interpreted as the proportion of the range of the standard normal curve (the process width) that falls within the engineering specification limits. If the process is not centered, an adjusted index Cpk is used instead. For a capable process, the Cp index should be greater than 1, that is, the specification limits would be larger than 6 times the sigma limits, so that over 99% of all items or parts produced could be expected to fall inside the acceptable engineering specifications. For a detailed discussion of this and other indices, refer to Process Analysis. In recognition of these efforts, the company has received a number of excellence awards for its management practices and quality standards. In 1998, Hino Motors Ltd. , and Toyota Tsusho Corporation obtained majority shareholding in the company after disinvestments by the other two founding sponsors. This decision to invest in Hinopak at a time when the countrys economy was passing through a depression and the sale of commercial vehicles was at an all time low reflects the confidence our Principals have in our company and their commitment to the Pakistani market. It is the enduring success of Hinopak that has made the Hino name and symbol of quality reliability and Hino vehicles a prize possession for its owners. By continuing to move forward and staying alert to ever-changing market social needs, Hinopak will continue to be a successful and well-respected corporate citizen of Pakistan. MISSION The mission of Hinopak Motors Limited is to provide the society with safe, economical, comfortable and environment friendly means of transportation by manufacturing and supplying commercial vehicles and services. To achieve this mission, we commit ourselves: To our individual institutional and international customers: to deliver high quality, safe, durable, reliable, comfortable, environment–friendly and economical products and services to their total satisfaction. To our employees: to foster corporate culture of mutual trust; respect for fundamental human rights at work; opportunities for professional growth and personal welfare so that they are proud of being a member of the â€Å"Hinopak Family†. †¢To the community and our nation: to contribute in economic and social development by providing means of transportation and by progressive localization of the vehicles. To the shareholders: to act in compliance with the norms expected of a subsidiary of the Toyota Group of companies and make a meaningful financial return to the shareholders. VISION â€Å"Total Customer Satisfaction, a set vision for the company. In pursuit new concepts have been introduced such as a mobile workshops, 3S/2S dealership facilities, training and free service camps for the vehicle owners and drivers†. Corporate Features Building on seventeen years of success, the Hinopak continues to play a leading role in marketing commercial vehicles with superior a nd advanced Japanese technology. Market Leader in Pakistan, holding over 65% of the truck and bus market share. First Pakistani automobile company and Hino affiliate to receive ISO-9001 certificate. Voluntary initiative for ISO 14001 certification. First company to export buses from Pakistan. Recipient of Quality Excellence Awards. First automotive company to introduce 3S concept in heavy-duty commercial vehicles market. First company to supply busses under Urban Transport Scheme in Pakistan. Recipient of Employers Federation of Pakistans Golden Jubilee Award for Human Resource and Industrial Relations. Recipient of Corporate Excellence Award from Management Association of Pakistan. Recipient of Employers Federation of Pakistans Golden Jubilee Award for Excellence in Productivity. Hinopak; Committed to Excellence Hinopak Motors Limited assembles, manufactures and markets world renowned Hino diesel trucks and buses in Pakistan. The Company has held the top position in the domestic market for medium and heavy-duty vehicles for 15 consecutive years and is highly acclaimed for quality and technological excellence. Backed by Hino’s expertise Hinopak has achieved standard of quality and excellence that rival the best in the region. With over 33,000 vehicles on road, Hino has gained 70% market share making it the largest manufacturer in medium and heavy-duty truck and bus industry in Pakistan. Hinopak’s product range has been designed and built in Hino’s traditions of automotive excellence to be the leader in its category and the main emphasis has been given to passengers’ safety comfort. Latest News Hinopak introduces Modern, Elegant and Reliable Bus Lineup or Comfortable and Safe Journey Hinopak has recently introduced new, modern, elegant and reliable models of Hino Roadliner Supreme air-conditioned Super Luxury Bus, Hino Senator Pride air-conditioned luxury coach and Rapidliner Deluxe Coach. These models have been designed and built in Hinopak’s traditions of automotive excellence to be the leader in its category. These new models are produced in line with international standards for passengers’ safety comforts and can be matched with any foreign made bus while they are also highly competitive in terms of cost. To demonstrate these models to the transporters, Hinopak has held displays all over Pakistan those displays were attended by large number of transporters and bus operators who appreciated the new models. Sponsors Hino Motors Ltd. , Japan Founded in 1910, Hino Motors, Ltd. is Japans oldest motor vehicle manufacturer. Since introducing Japans first automobile in 1908, Hino has been developing and manufacturing superior vehicles that serve business and society. Over the years the range of Hino’s trucks and buses has made their mark in over 140 countries worldwide. Today Hino Motors is the leading manufacturer of medium and heavy-duty commercial vehicles in Japan and the 2nd largest in the world. In this age of high technology, globalization and advanced data communication, individual values are diversifying. Hino is dedicated to putting the customers first and maintaining high standards of quality. Toyota Tsusho Corporation (TTC) Established in 1948, Toyota Tsusho Corporation (TTC) is a trading company within the Toyota Group. TTC has an extensive network of representative offices all over the world and offers a vast variety of goods and services to its customers. As a leading player in the automotive business TTC provides additional support to Hinopak with its expert advice and knowledge of world markets. Backed by the strong network of Hino Motors, Limited Japan and the versatility of Toyota Tsusho Corporation (TTC) that provides us the competitive edge, we at Hinopak believe in giving our customer the very best and we pledge to continue for â€Å"Total Customer Satisfaction†. Export Market Hinopak is proud to be Pakistan’s first automobile company to export buses. After successfully establishing itself as the market leader at home, Hinopak proceeded to explore its product potential for the export market. This quest met with initial success when it made its first historic sale well over a decade ago, in 1990 Hinopak exported its first bulk order of buses to U. A. E. Follow up orders were soon placed, ensuring the satisfaction of customers at home and abroad. This entry into the export market was an important milestone for Hinopak and lead Pakistan into an exciting new era for the automotive industry, fulfilling Hinopak’s commitment towards the economic growth of Pakistan. PRODUCT LINE Buses The largest Manufacturer of Buses in Pakistan, Hinopak is fully-equipped to design and manufacture a wide range of Bus Chassis and all types of Bus Bodies. Hinopak’s Bus Line Up includes the Roadliner Supreme Luxury Bus for long journeys, Citiliner Intercity Buses, Citiliner Urban Buses and the luxury Senator Coach and Rapidliner Deluxe Coaches. Hinopak delivers only the safest most reliable products and remains the Pioneer in supplying the largest number of Urban Buses those are successfully facilitating the commuters of Punjab and Sindh. The new Bus line up is built upon reliable AK1J and RK1J (Rear engine bus) Series that offer straight and kick up frame options for intercity and intra-city usage. Both newly introduced series can be suitable for a wide variety of bus bodies. The kick up frame for inter-city operation offers more space for storage and luggage while the larger door s and low boarding height of the straight frame allow passengers greater comfort and convenience. Trucks The New Hino 500 Series is a dynamic combination of power, economy, style and safety. Vast improvements in engine technologies have allowed us to create Engines with more horse power while offering lower fuel consumption. These dynamic new vehicles featuring revolutionary technologies such as multi valves engine, new air intake system, turbocharger with intercooler, overhead cams, heavy duty clutch, synchronized transmission and power steering promise to change the face of transportation with new standards in comfort, luxury, safety and especially economy.