Chapter 16
Quality Management
Abstract
This chapter gives a history of and explains the need for quality management. The quality management definitions are first listed and then described in detail. A diagram shows the issuing sequence of the quality-related documentation. Other diagrams include a cause and effect diagram, a Pareto chart and a quality failure table. Sample formats for quality assurance approval documents and compliance requests are also included.
Keywords
Cause and effect diagram; Pareto chart; Quality assurance; Quality audit; Quality control; Quality management; Quality plan; Total quality management (TQM)
Quality is remembered long after the price is forgotten.
Gucci.
Quality (or performance) forms the third corner of the time–cost–quality triangle, which is the basis of project management.
A project may be completed on time and within the set budget, but if it does not meet the specified quality or performance criteria it will at best attract criticism and at worst be considered a failure. Striking a balance between meeting the three essential criteria of time, cost and quality is one of the most onerous tasks for a project manager, and in practice usually one will be paramount. When quality is synonymous with safety, as with aircraft or nuclear design, there is no question of which point of the project management triangle is the most important. However, even if the choice is not so obvious, a failure in quality can be expensive and dangerous, and can destroy an organization’s reputation far quicker than it took to build up.
Quality management is therefore an essential part of project management, and as with any other attribute, it does not just happen without a systematic approach. To ensure a quality product it has to be defined, planned, designed, specified, manufactured, constructed (or erected) and commissioned to an agreed set of standards that involve every department of the organization from top management to dispatch.
It is not possible to build quality into a product. If a product meets the specified performance criteria for a minimum specified time, it can be said to be a quality product. Whether the cost of achieving these criteria is high or low is immaterial, but to ensure that the criteria are met will almost certainly require additional expenditure. If these costs are then added to the normal production costs, a quality assured product will normally cost more than an equivalent one that has not gone through a quality control process.
Quality is an attitude of mind, and for it to be most effective, every level of an organization should be involved and committed to achieving the required performance standards by setting and operating procedures and systems which ensure this. It should permeate right through an organization from the board of directors down to the operatives on the shop floor.
Ideally, everyone should be responsible for ensuring that his or her work meets the quality standards set down by the management. To ensure that these standards are met, quality assurance requires checks and audits to be carried out on a regular basis.
However, producing a product that has not undergone a series of quality checks and tests and therefore not met customers’ expectations could be much more expensive, as there will be more returns of faulty goods and fewer returns of customers. In other words, quality assurance is good business. It is far better to get it right first time, every time, than to have a second attempt or carry out a repair.
To enable this consistency of performance to be obtained (and guaranteed), the quality assurance, control, review and audit procedures have to be carried out in an organized manner and the following functions and actions need to be implemented:
1. The quality standards have been defined.
2. The quality requirements have been disseminated.
4. The staff and operatives have been trained.
5. The materials have been tested and checked for conformity.
6. Adequate control points have been set up.
7. The designated components have been checked at predetermined stages and intervals.
8. A feedback and rectification process has been set up.
9. Regular quality audits and reviews are carried out.
10. All these steps, which make up quality control, are enshrined in the quality manual together with the quality policy, quality plan and quality programme.
History
The first quality standards were produced in the USA for the military as MIL-STD and were subsequently used by NATO.
In the 1970s, the MOD issued the Defence Standard series 05 to 20 (Def. Std.) based on the American MIL-Q-9858A, but it was then superseded by 15 parts of the Allied Quality Assurance Publication (AQAP).
Defence contractors and other large companies adopted the MOD system until BSI produced the BS 5750 series of Quality Systems in 1979. These were updated in 1987 and then became an international standard (ISO), the ISO 9000:1987 series, which also covers the European standard EU 29,000 series.
To understand the subject, it is vital that the definitions of the various quality functions are understood. These are summarized in the following list and explained more fully in the subsequent sections.
Quality Management Definitions
Quality
The totality of features and characteristics of a product, service or facility that bear on its ability to satisfy a given need.
Quality Policy
The overall quality intentions and direction of an organization as regards quality, as formally expressed by top management.
Quality Management
Quality Assurance (QA)
All planned and systematic actions necessary to provide confidence that an item, service or facility will meet the defined requirements.
Quality Systems (Quality Management Systems or QMS)
These include the organizational structures, responsibilities, procedures, processes and resources for implementing the quality management.
Quality Control (QC)
Those quality assurance actions that provide a means of control and measure the characteristics of an item, process or facility to established requirements.
Quality Manual
These are a set of documents that communicates the organization’s quality policy, procedures and requirements.
Quality Programme
A contract (project)-specific document that defines the quality requirements, responsibilities, procedures and actions to be applied at various stages of the contract.
Quality Plan
A contract (project)-specific document defining the actions and processes to be undertaken together with the hold points for reviews and inspections. It also defines the control document, applicable standards, inspection methods and inspection authority. This authority may be internal and/or may include the client’s inspectors or an independent/statutory inspection authority.
Quality Audit
A periodic check to ensure that the quality procedures set out in the quality plan have been carried out.
Quality Reviews
Total Quality Management (TQM)
The company-wide approach to quality beyond the prescriptive requirements of a quality management standard such as ISO 9001.
Explanation of the Definitions
Quality Policy
The quality policy has to be set by top management and issued to the whole organization, so that everyone is aware what the aims of management regarding quality are. The quality policy might be to produce a component that lasts a specific period of time under normal use, withstands a set number of reversing cycles before cracking, withstands a defined load or pressure or, on the opposite scale, lasts only a limited number of years so that a later model can be produced to replace it. A firm of house builders might have a quality policy to build all their houses to the highest standards in only the most desirable locations, or the top management of a car manufacturer might dictate to their design engineers to design a car using components that will not fail for at least 5 years. There is clearly a cost and marketing implication in any quality policy that must be taken into account.
Quality Management
Quality management can be divided into two main areas: quality assurance (QA) and quality control (QC). All the quality functions, such as the procedures, methods, techniques, programmes, plans, controls, reviews and audits, make up the science of quality management.
It also includes all the necessary documentation and its distribution, the implementation of the procedures and the training and appointment of quality managers, testers, checkers, auditors and other staff involved in quality management.
Quality Assurance
Quality assurance (QA) is the process that ensures that adequate quality systems, processes and procedures are in place. It is the term given to a set of documents that provide evidence of how and when the different quality procedures and systems are actually being implemented. These documents give proof that quality systems are in place and adequate controls have been set up to ensure compliance with the quality policy. To satisfy him- or herself that the quality of a product he or she needs is to the required standard, the buyer may well ask all tenderers or suppliers to produce their quality assurance documents with their quotations or tenders.
Guidelines for quality management and quality assurance standards are published by various national and international institutions including the British Standards Institution, which publishes the following quality standards:
| ISO 9000 | Quality management and quality assurance standards |
| ISO 9001 | Quality systems – model for quality assurance in design and development, production, installation and servicing |
| ISO 9002 | Quality systems – model for quality assurance in production and installation |
| ISO 9003 | Quality systems – model for quality assurance in inspection and testing |
| ISO 9004 | Guide to quality management and quality systems elements |
| ISO 10006 | Guidelines for quality in project management |
| ISO 10007 | Guidelines for configuration management |
Quality Systems
Quality systems or quality management systems, as they are often called, are the structured procedures that in fact enable quality control to be realized. The systems required include the levels of responsibility for quality control, such as hierarchical diagrams (family trees) showing who is responsible to whom and for which part of the quality spectrum they are accountable for, as well as the procedures for recruiting and training staff and operatives. Other systems cover the different quality procedures and processes that may be common to all, as well as for all the components or specifics for particular ones.
Quality systems also include the procurement, installation, operation and maintenance of equipment for carrying out quality checks. These cover such equipment as measuring tools, testing bays, non-destructive testing equipment for radiography (x-rays), magnetic particle scans, ultrasonic inspection and all the other different techniques being developed for testing purposes.
Documentation plays an important role in ensuring that the tests and checks have been carried out as planned, and the results accurately recorded and forwarded to the specified authority. Suitable action plans for recovering from deviations of set criteria will also form parts of the quality systems. The sequence of generating the quality-related documentation is shown in Fig. 16.1.
Quality Control
The means to control and measure characteristics of a component, and the methods employed for monitoring and measuring a process or facility are parts of quality control. Control covers the actions to be taken by different staff and operators employed in the quality environment and the availability of the necessary tools to enable this work to be done. Again, the provision of the right documentation to the operatives and their correct, accurate and timely completion has to be controlled. This control covers the design, material specification, manufacture, assembly and distribution stages. The performance criteria are often set by the feedback from market research and customer requirements, and confirmed by the top management.
Quality Manual
The quality manual is in fact the ‘bible’ of quality management. It is primarily a communication document which, between its covers, contains the organization’s quality policy, various quality procedures, quality systems to be used and the list of personnel involved in implementing the quality policy. The manual will also contain the various test certificates required for certain operatives such as welders, the types of tests to be carried out on different materials and components, and the sourcing trails required for specified materials.
Quality Programme
This is a document written specifically for the project in hand and contains all the requirements for that project. Various levels and stages for quality checks or tests will be listed together with the names of the staff and operatives required at each stage, along with the reporting procedures and the names or organizations authorized to approve or reject the results, and instruct what remedial action (if required) has to be taken, especially when concessions for non-compliance are requested.
Quality Plan
This is also a contract-specific document that can greatly vary in content and size from company to company. As a general rule it defines in great detail:
1. The processes to be employed;
2. The hold points of each production process;
3. The tests to be carried out for different materials and components, including:
3.1 Dimensional checks and weight checks
3.2 Material tests (physical and chemical)
3.3 Non-destructive tests (radiography, ultrasonic, magnetic particle, etc.)
3.4 Pressure tests
3.5 Leak tests
3.6 Electrical tests (voltage, current, resistance, continuity, etc.)
3.7 Qualification and capability tests for operatives
4. The control documents including reports and concession requests;
5. The standards to be applied for the different components;
6. The method of inspection;
7. The percentage of items or processes (such as welds) to be checked;
8. The inspection authorities, whether internal, external or statutory and
9. The acceptance criteria for the tests and checks.
Most organizations have their own standards and test procedures but may additionally be required to comply with the client’s quality standards. A sample quality plan of components of a boiler is shown in Fig. 16.2.
The quality plan is part of the project management plan and because of its size is usually attached as an appendix.
Quality Audit
To ensure that various procedures are implemented correctly, regular quality audits must be carried out across the whole spectrum of the quality systems. These audits vary in scope and depth and can be carried out by internal members of staff or external authorities. When an organization is officially registered as being in compliance with a specific quality standard, such as ISO 9000, an annual audit by an independent inspection authority may be carried out to ensure that the standards are still being met.
Quality Reviews
As manufacturing or distribution processes change, a periodic review must be carried out to ensure that the quality procedures are still relevant and applicable in light of the changed conditions. Statutory standards may also have been updated, and these reviews check that the latest versions have been incorporated.
As part of the reviewing process, existing, proposed or new suppliers and contractors have to confirm their compliance with the quality assurance procedures. Fig. 16.3 shows the type of letter that should be sent periodically to all vendors.
All the earlier procedures are sometimes described as the ’tools’ of quality management to which following techniques can be added:
• Failure mode analysis (cause and effect analysis)
• Pareto analysis
• Trend analysis
Failure Mode Analysis (Cause and Effect Analysis)
This technique involves selecting certain (usually critical) items and identifying all the possible modes of failure that could occur during its life cycle. The probability, causes and impact of such a failure are then assessed and the necessary controls and rectification processes are put in place. Clearly, as with risk analysis, the earlier in the project this process is carried out, the more opportunity there is to anticipate a problem and, if necessary, change the design to ‘engineer’ it out.
The following example illustrates how this technique can be applied to find the main causes affecting the operability of a domestic vacuum cleaner.
The first step is to list all the main causes that are generally experienced when using such a machine. These causes (or quality shortcomings), which may require a brainstorming session to generate them, are:
• Electrical
• Physical (weight and size)
• Mechanical (brush wear)
The second step is drawing a cause and effect diagram as shown in Fig. 16.4, which is also known as an Ishikawa or fishbone diagram, from which it is possible to see clearly how these causes affect the operation of the vacuum cleaner.
The third step requires all the sub-causes (or reasons) of a main cause to be written against the tributary lines (or fish bones) of each cause. For example, the sub-causes of electrical failure are the lead being too short, thus pulling the plug out of the socket or hauling the cleaner by the lead and causing a break in the cable.
The last step involves an assessment of the number of times over a measured period each cause has resulted in a failure. However, it is highly advantageous to concentrate on those causes that are responsible for the most complaints, and when this has been completed and assessed by applying the next technique, Pareto analysis, appropriate action can be taken to resolve any problem or rectify any error.
Pareto Analysis
In the 19th century, Vilfredo Pareto discovered that in Italy 90% of income was earned by 10% of the population. Further study showed that this distribution was also true for many other situations from political power to industrial problems. He therefore formulated Pareto’s law, which states that ‘In any series of elements to be controlled, a small fraction in terms of the number of elements always account for a large fraction in terms of effect’.
In the case of the vacuum cleaner, this is clearly shown in the Pareto chart in Fig. 16.5, which plots the impact Y in terms of percentage of problems encountered against the number of causes X identified. The survey of faults shows that of the four main causes examined, inadequate dust collection is responsible for 76% (nearly 80%) of the failures or complaints. This is why Pareto’s law is sometimes called the 80/20 rule.
The percentage figure can be calculated by tabulating the causes and the number of times they resulted in a failure over a given period, say 1 year, and then converting these into a percentage of the total number of failures. This is shown in Fig. 16.6. Clearly, such ratios are only approximate and can vary widely, but in general only a relatively small number of causes are responsible for the most serious effects. Anyone who is involved in club committee activities will know that there are always a few keen members who have the greatest influence.
Trend Analysis
Part of the quality control process is to issue regular reports that log non-conformance, accepted or non-accepted variances, delays, cost overruns or other problems. If these reports are reviewed on a regular basis, trends may be discerned which, if considered to be adverse, can then be addressed by taking appropriate corrective action. At the same time the opportunity can be taken to check whether there has been a deficiency in the procedures or documents and whether other components could be affected. Most importantly, the cause and source of a failure has to be identified, which may require a review of all the suppliers and subcontractors involved.
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