the practical application of iso 9001 and iso/ts 16949 …

CIE42 Proceedings, 16-18 July 2012, Cape Town, South Africa © 2012 CIE & SAIIE

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THE PRACTICAL APPLICATION OF ISO 9001 AND ISO/TS 16949 TO THE MASS PRODUCTION OF MOTOR INDUSTRY COMPONENTS

P.G. Blaine1*, P.J. Vlok2 and R.T. Dobson1

1Department of Mechanical and Mechatronic Engineering Stellenbosch University, South Africa

[email protected]

2Department of Industrial Engineering Stellenbosch University, South Africa

ABSTRACT

Quality, as a scientific concept, is a characteristic which is generally little understood and difficult to define. The International Organisation for Standardisation (ISO) is an inter-governmental organisation based in Switzerland tasked with drawing up standards for a multitude of applications in business, government and society. The standards which specifically deal with quality are the ISO9000 series and, specifically for the motor industry, ISO/TS 16949. These form the basis for ever more universally accepted standards for quality management systems. ISO/TS 16949 is a derivative of ISO 9001 with additional requirements centred on the use of statistical tools with the purpose of developing manufacturing systems which will warrant that product and service comply perfectly with the customer’s specifications and requirements. The objective is to eliminate the need to inspect outgoing or incoming product, saving time and expense while building confidence and trust between supplier and customer.

This paper describes the effects on a powder metallurgy facility which manufactured mass produced components principally for the motor industry. The techniques and principles developed can be used in any manufacturing facility with consequent savings in time and money. An example is given of the use of Pre-Control Charts to ensure the production of acceptable parts. The use of Pre-Control Charting empowered and increased the motivation of factory personnel who, in the particular facility described, were generally often technically illiterate.

The importance of the application of asset care to all elements used in the manufacturing process is stressed.

1 INTRODUCTION

In any business, quality in service and product is paramount. However, it is very often assumed that quality refers only to the state of compliance of the


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physical product that is delivered to the customer; that quality concerns only the quality inspection department. Often production absolves itself of responsibility by stating that it is the duty of inspection alone to strive for perfection. Nothing could be further from the truth. Contributions needed to ensure the quality of the service and final product rest with every department and every individual in the supplier organisation. ISO 9000, SABS [2] places emphasis on the total involvement of all sections of the organisation by promoting a process-based quality management system. The interconnection between each department in an organisation is very clearly shown in the process map of Figure 1 which was developed for the subject manufacturer.

The supplier strives for excellence. The customer looks for quality in service and product and will judge the supplier on its overall performance. The customer needs to feel confident in all aspects of its relationship with the supplier.

So, what is Quality? Quality is defined in ISO 9000, SABS [2] as

”3.1.1 quality [the] degree to which a set of inherent characteristics fulfil requirements”

But there is no quantitative measurement implying that the characteristics of quality are general knowledge and universally understood. On that basis, both standards describe criteria for an acceptable Quality Management System (QMS) with a view to ensuring ”Quality”. In order for this to be achieved,

ñ the product must be correct to specification

ñ invoicing and financial documentation must be timely and correct

ñ customer-supplier personal relationships must be transparent and cooperative

ñ there must be mutual trust between customer and supplier


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ñ technical interaction must be professional, honest, accurate and open.

Figure 1: Process Map Which Forms Part Of The Policy Documents

In the automotive field, quality means the supply of product which complies in every aspect to the customer’s specifications every time without fail, coupled with excellent and efficient service. Ultimately, and in fact, quality will result in customers being so confident in the supplier’s products and systems that they no longer consider it necessary to inspect any delivered product. The components, which are assumed to conform to specification, are immediately put into the assembly line. However, one faulty component can bring the whole customer manufacturing process to a halt with huge negative financial and strategic consequences for both customer and supplier. The customer’s confidence in the supplier’s quality will be seriously undermined. That confidence will have to be rebuilt; a slow, expensive and frustrating exercise.

The requirement that all product be perfect is emphasised by the fact that motor manufacturers (OEMs) now require proof that the product delivered not only is within specifications, but that a batch statistical analysis shows that the range of measurement of each and every dimension is within ±6σ, Martino [1], or a maximum of 3.4 non-conforming parts per million. Since batches are generally be less than 100,000 parts, 0.34 non-conformances effectively guarantees perfection. The ±6σ standard is only attainable with the use of


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manufacturing process controls and systems throughout all aspects of the design and production of the component.

What is also important to understand is that, in all the statistical analysis processes used, a normal distribution is assumed, Bhote [8]. This is not always true, but the methods are used all the same.

In everyday manufacture, a non-conformance rate of 5% is often acceptable, at least on some dimensions. In most excellent engineering operations, holding ±3σ is expected, that is a maximum 0.27% of all parts do not conform. This means that, in a 100,000 batch, it is acceptable to have 270 non-conforming components.

It is possible to reach these levels of excellence by the application of ISO 9000, SABS [2] and ISO 9001, SABS [3] principles. This goal is made even more realisable with the use of ISO/TS 16949, SABS [4], which lays greater emphasis on product design methodologies, management systems and Statistical Process Control (SPC).

There is little common conception of the huge cost in effort, time, money and morale of producing rubbish. However, attitudes are changing as is shown by customers now requiring that suppliers hold product liability insurance and that the costs of non-conformances be quantified continually and made known to staff and management regularly.

2 HISTORY

Ford was the first motorcar manufacturer to produce, in the 1970s, a quality management system (QMS) specification which they called Q101. Over time it evolved into Q1. The other major American manufacturers, Chrysler and General Motors, produced their own standards. This led to suppliers having to comply with sometimes conflicting requirements. As a result, the big three combined their requirements into QS 9000. Other international manufacturers soon produced their own standards, which they made mandatory for their suppliers. These standards were merged into national standards. Suppliers were asked to build and certify their QMS according to the rules and regulations of their customers’ national standards organisations, such as VDA (Germany), AIAG (North America), AVSQ (Italy), FIEV (France) and SMMT (UK). This lead to a chaotic state of affairs because, even though the purpose of all the standards was the same, they varied in certain aspects, mainly in the required documentation. The result was that, for instance, a supplier needed to provide two different sets of documentation for Daimler (VDA 6.1 for Germany) and Chrysler (QS 9000 for America), even though the supplier delivered only to one company.

Meanwhile Japanese motor manufacturers had started to apply statistical methods to production using the work of Shewhart [5] and Deming [6]. Ironically, these methodologies had been rejected by American motor companies as being too complicated and costly. There is an allegorical story


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of the company who ordered gearboxes from a Japanese supplier, specifying that two faulty boxes were acceptable. When the order was delivered, there were the two faulty boxes, packaged separately. The ”acceptability” of supplying faulty components arose from the then general use of Acceptable Quality Levels (AQL) as defined in MIL-STD-105, USDoD [7]. There are other standards, mainly published by the military during the second world war, which are all essentially the same. These standards grew out of the need to control the quality of war material supplied as the manufacturing processes tended towards mass production. The system inherently accepted that it was impossible to make components without some of them being out of specification. The AQL system specified, for any particular batch size, the number of random samples to be taken and the allowable number of out-of-specification parts that would still allow the batch to be acceptable. The concept of quality of supply was recognised by specifying an Acceptable Quality Level (AQL). So, referring to Table 1 extracted from MIL-STD-105, and assuming the batch size was 50,000 parts, and a mutually agreed AQL of the commonly used 0.4, then the supplier would be required to take a random sample of 500 parts. Only if 2 non-conformances were found in the sample was the batch rejected and a 100% sort required. Put another way, the supplier would be allowed a non-conformance rate of 1 in 500, so it would follow that the batch could well have 100 bad parts. If the present standard were to be applied, the supplier would be allowed 0.2 bad parts, or, in practice, none at all. The ”acceptable” supply of 100 bad parts motivated Ford to demand that the quality of product delivered by their suppliers be improved. The non-conformances were costing too much in time, money and reputation. The market was moving to Japanese cars because of their reliability.

Table 1: MIL STD 105 Single Sampling Plan, USDoD [7]


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The issue of quality and its management slowly became ever more important as the consumer demanded ever more reliable products. Early motor cars were renowned for breaking down. In the 1930s they were sold with a standard 90 day guarantee as against the present 5 years. They were unacceptably unreliable by modern standards. With the application of Shewhart and Deming’s ideas and methods, the Japanese, and particularly Toyota, started to produce vehicles which seldom if ever broke down if maintained correctly. The Corolla, one of the first reliable cars, has earned an enviable reputation for Toyota as a result.

In an effort to improve quality, and to establish a standard which would be universal, ISO published a QMS which it designated ISO 9000, SABS [2]. The ISO 9000 family of standards, listed below, has been developed to assist organisations, of all types, applications and sizes, to implement and operate effective quality management systems.

ñ ISO 9000, SABS [2] describes the fundamentals of and specifies the terminology for quality management systems.

ñ ISO 9001, SABS [3] specifies requirements for a QMS where an organization needs to demonstrate its ability to provide products that fulfil customer and applicable regulatory requirements and aims to enhance customer satisfaction.

ñ ISO 9004, SABS [10] provides guidelines that consider both the effectiveness and efficiency of the QMS. The aim of this standard is improvement of the performance of the organization and satisfaction of customers and other interested parties.

The first editions of the standard included ISO 9002 and ISO 9003, the


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principles of which have been included in ISO 9001, making them redundant. ISO 9001 standard has become universal and applied to a multitude of industries and services. It is becoming a requirement of any business as a mark of excellence in service and product. Export of product, especially to the European Union, is no longer possible without accreditation.

American and European original equipment manufacturers (OEM), however, found that ISO 9001 did not provide the level of quality they needed, especially since they were basing their manufacturing strategy on the assumption that all components supplied would conform to specifications and be delivered ”just-in-time”. As a result, a task team was formed by ISO known as the International Automotive Task Force (IATF), which included representatives of all the major motor manufacturers. This group produced ISO/TS 16949, SABS [4], first published in 2002, specifically for the automotive industry. It is probably the most advanced QMS in use internationally and compliance is mandatory on all car part suppliers to OEMs.

3 APPLICATION

The application of ISO 9001 and ISO/TS 16949 is all encompassing and focusses on the consistent supply of perfect product. Both standards cover all aspects of a production or business facility including management, finance, contract review, raw materials purchasing and control, process design and control, part and facility inspection, plant maintenance, logistics, records, training. ISO/TS 16949, as mentioned above, is an extension of ISO 9001. They both require the establishment of a system where every aspect of the facility is continually controlled, updated and audited. The underlying concept is based on continual improvement, defect prevention and the reduction of variation and waste. It is essential that there is total management commitment. At first sight, the requirements are very onerous requiring a large investment in equipment and training, but the benefits are huge, both for the component supplier and the OEM. The production of scrap and the receipt of rejections is massively reduced. Confidence is gained by the supplier personnel as they take pride in their work and start to realise that the system gives them power and control over what they produce. There is no better motivator than the knowledge that the team is producing product that the customer will accept, and better, accept without question.

The company from which data is taken was a mass producer of small, complex and highly toleranced ferrous and non-ferrous components made on continuous production lines using powder metallurgy technology. Average production rates were 1000 parts per hour through a multi-stage production process, with batches ranging up to 50,000 parts. When the OEM informed the company that product would no longer be inspected by their receiving department the staff felt empowered and proud. Rejections, after the installation of the system, were treated with disbelief and horror.

In this work, just the engineering aspects from receipt of the request for


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quote (RFQ) through to product acceptance by the OEM and then series production will be covered.

3.1 Request For Quotation (RFQ)

The OEM would send a Request for Quotation (RFQ) usually with all the relevant documents such as drawings and material specifications. ISO/TS 16949 requires that the proposed product be thoroughly analysed both between customer and supplier, and between company departments. The supplier needs to fully understand what the customer wants and the customer needs to know that the supplier has the capacity and equipment to manufacture the component. The customer needs to know that the quality of product and supply is guaranteed.

In order to comply, the drawings and specifications were studied in detail. As an aid to the design analysis, an Initial Feasibility Study (IFS) was completed. An example is shown in Table 2, together with the marked up component drawing, to which the IFS refers, shown in Figure 2. These were updated in a continual feedback system until customer and supplier fully understood each other and were in agreement in all aspects of the project.

Figure 2: Marked Up Component Drawing

Table 2: Initial Feasibility Study (Partial)


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At the same time, the production process was designed, as shown in Table 3, so that the required machines and machine rates could be specified. The proposed equipment was studied to ensure that those selected were capable of making the component in the numbers and time required and were not otherwise committed. Often the customer would require proof that the supplier was capable of meeting the specifications set.

As soon as these aspects had been agreed in-house, the necessary tooling assembly was designed. The design was then sent to the production department for criticism and improvement. Again a continual feedback process was used until all agreed.

The basic requirements for the planning stage of a project are laid down in Section 7 of ISO 9000 and ISO/TS 16949 entitled ”Product Realisation”. The manner in which these criteria are satisfied is up to the organisation to specify in its procedures and work instructions.

Table 3: Production Process Design Flow Plan

With this information, the sales department could prepare a quotation detailing costs and delivery times

3.2 Prototype Production

If an order was received from the OEM, the tools were designed in detail and sent for manufacture and the necessary extra equipment, if required, was ordered. When these buy-outs are received, they were checked and sent to the tool setters to develop the process.

During this time, a log was kept of all settings and changes so that, when the process parameters had been fixed, process control charts could be written.

Process control charts specify all parameters and tolerances for manufacture at each and every process stage. The back-of-a-cigarette-box catastrophe is thus eliminated. No matter who is concerned, the whole production process is defined so that product can be produced at any time, even if the original people who developed the process are not available. The supplier does not need to rely on anyone’s memory or be sabotaged by anyone’s spitefulness.


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As soon as acceptable product was produced, the process control charts were completed and issued and a pilot run of some 1000 parts manufactured. An example of the first stage is shown in Table 4. These initial parts were analysed statistically and all properties and processes documented. The initial samples with the inspection results were sent to the customer for acceptance.

3.3 Series Production

On the customer’s acceptance of the samples and confirmation of order, series production was started using the Process Control Charts. Those characteristics designated as needing SPC were notated and monitored using the frequency and methods specified.

Table 4: First Stage Production Process Control Plan

Figure 3: Standard X-Bar R Chart, ASQC [8]


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Most commonly, Xbar-R charting is used, but these require sophisticated and expert chartists to analyse and action. An example is shown in Figure 3. This charting method is based on theory which assumes a normal distribution, Bhote [8], ASQC [8]. Even though this is not always true, the methods are used all the same. Before Xbar-R charting method is used, the process must be shown to be shown to be ”in control”. When control has been proven, further calculations have to be made to define the upper and lower control limits.

While production is running, the inspector or operator must calculate the average and range of 5 consecutive components taken at specified intervals. The results and trends then have to be analysed according to specified rules, requiring a highly trained and knowledgeable person. The process is open to calculation error, aggravated by the very low standards of technical competence of the average employee. Furthermore the control limits must be re-calculated periodically.

Another method, known as Pre-Control Charting, Bhote [9] and ASQC [8], offered simplicity, efficiency, accuracy, effectiveness and ease of use. This method requires the inspector or machine operator to plot, on a pre-issued chart, as shown in Figure 4, the actual measurements of 2 consecutive components, and to make sure the results stay between clear and obvious bounds coloured, for simplicity, green, yellow and red. The system worked exceedingly well. In one example, the factory found it impossible to keep the length of a bush within specification, let alone ±3σ. Within a day of installing the pre-control method, the part was well within specification and, in the 10 years of subsequent production, no non-conforming part ever left the factory. What made this result even more remarkable was that the control was exercised by a team with minimal education. The supervisor at the time had only 10 years of schooling. Even those who were functionally illiterate were trained ab initio in a short time and understood what was required and what was meant.

Pre-Control Charting is simple and well described by Bhote [9] and does not require a normal distribution of the controlled variable. The upper and lower customer specified limits are placed in the upper and lower limits of the yellow band of the chart, and the range formed is divided into quarters, giving the upper and lower limits of the green band. Two consecutive parts are taken directly from the production and measured. The results are plotted on the chart. If two points are in the yellow bands or any one in the red, then the process is stopped, the parts made since the previous inspection are


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isolated and the machine reset until the inspectors were satisfied to allow

production to continue. The criterion for allowing production to start or continue is that 5 consecutive measurements must be in the green band.

Figure 4: Pre-Control Chart

3.4 The Cost Of Inspection

The process control plan has at least one page of instructions for every step in the manufacturing process, including the check of the final product. MIL-STD-105 specifies that, in a run of 50,000 parts, a random sample of 500 parts needs to be inspected. In our particular example, the final inspection process control specification is shown in Table 5. It covers three pages, but only the first is reproduced here because the others state properties other than measurements.

Table 5: Final Stage Production Process Control Plan

There were 10 dimensions that had to be measured and 2 physical properties. MIL-STD-105 would require 5,000 readings to be taken and recorded. If we


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assume each measurement takes 30 seconds and 15 seconds to record, then the final inspection will take 62.5 hours or 7.8, 8 hour man-days.

In practice, the chance of an inspector correctly reading and recording all 5,000 results is virtually zero. It is very simple to demonstrate human error of this kind. The component measurements can be digitised at great cost, with every component needing its own jig and software. Even then there is the strong possibility that the inspector could be lax in using the jig resulting in erroneous results. Ideally the supplier and customer should be so confident of the process that they eliminate final and receiving inspection all together. With 25 randomly selected parts taken from a batch, it is possible to say, with a high degree of certainty, that the batch is within specification. If the analysis does indeed show there are non-conforming parts, it is possible to calculate how many there are which can be removed by sorting.

In the case mentioned, 25 components were randomly selected and the measurements recorded on a statistical inspection report (SIR) shown in Table 6. The report automatically calculated the statistical data as shown. The value of the production capability index, Cp, is the ratio of the size of the customer specified tolerance band to 6σ for each dimension measured. Any value at or above 1 showed that the dimension was within specification


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Table 6: Sample Statistical Inspection Report

3.5 Asset Care

The whole system depends critically on the excellence of the equipment and resources being used. Therefore the measuring instruments are regularly calibrated and planned maintenance of production equipment conducted. Both require to be recorded as completed so as to ensure excellent, consistent and continual asset care which guarantees the validity of measurements and results.

4 DISCUSSION AND CONCLUSIONS

Although this paper is concerned, to a great extent, with the application of ISO 9001 and ISO/TS 16949 to a commercial production facility making mass produced parts for auto-mobiles, it is applicable to any facility, if necessary, in a modified form.

However, it is imperative that management is obviously dedicated to the system. It is also absolutely important that functioning and reliable resources in people, machines and equipment are available. Without that guarantee, it


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is just not possible to manufacture to present day quality and standards demanded by global customers.

Having unreliable or incapable production equipment or facilities will eventually cause a breakdown in the supply of conforming product. This will inevitably result in forcing a production line stop, which will have catastrophic consequences financially and to supplier-customer relations.

Modern industrial strategies rely on the ability of suppliers to deliver perfect product as and when required. This requires that all the supplier’s resources must be kept in perfect condition. Personnel must be informed and believe in the system. Measuring equipment must be perfect and constantly maintained. Production equipment must be kept in excellent condition using preventive maintenance and planned replacement. Measuring instruments must be continually calibrated and checked.

Every single resource in the company, including personnel, contributes, in a meaningful way, to the excellence of the final product and to the quality of the company’s output. Any non-conformance adversely affects every other operation or process, every other asset. As a result, plans, based on good reliable data, can be made to ensure product quality and the availability and excellence of all the resources required for production.

The resultant elimination of non-conforming product has huge financial and confidence-building advantages. Inspection is reduced, especially for the customer, to a minimum. The need for sorting, re-working and replacement production is eliminated. Where they occur, the causes are mostly relatively easy to identify and corrective actions can speedily be introduced.

The application of the standards has a definite and positive effect on company morale as employees realise that they are able to control the quality of their output. This aids the achievement of excellence and the quest for continual improvement.

5 REFERENCES

[1] Martino, D. 2001. QSM 754 Six Sigma Applications. The National Graduate School of Quality Management,

[2] ISO 9000:2005. Quality management systems : Fundamentals and vocabulary. South African Bureau of Standards.

[3] ISO 9001:2008. Quality management systems : Requirements. South African Bureau of Standards.

[4] ISO/TS 16949:2009. Quality management systems – Particular requirements for the application of ISO 9001:2008 for automotive production and relevant service part organizations, South African Bureau of Standards.

[5] Shewhart, W. 1931. Economic Control of Quality of Manufactured Product. D.Van Nostrand Company.


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[6] Shewhart, W. and Deming, W. 1939. Statistical method from the viewpoint of quality control. The United States Department of Agriculture.

[7] MIL-STD-105D. Military Standard. 1963. Sampling procedures and tables for inspection by attributes. United States Department of Defense.

[8] ASQC/AIAG Task Force. 2005. Statistical Process Control. AIAG.

[9] Bhote, K.R. and Bhote, A.K. 2000. World Class Quality; Using Design of Experiments to make it happen. American Management Association.

[10] ISO 9004:2009 Managing for the sustained success of an organization -- A quality management approach. South African Bureau of Standards.