Quality Management: An Effective Recipe for a QM System

Quality Management: An Effective Recipe for a QM System

By Werner Bergholz, QTEAM and Jacobs University Bremen e-mail: wbergholz@qteam.co

A Quality Management system is not just “nice to have” but a MUST.

In a contribution to the Grid in Dec 2014 it was pointed out that for photovoltaics manufacturing and installation, quality management is a key success factor. The main reason is that quality cannot be “tested into” PV cells and/or modules but must be “made” at every single production step along the whole value chain, starting with materials, and ending with the installation of the PV system. The ONLY way to “manufacture quality PV products” is to have a quality management system in place that REALLY works.

This contribution will describe how implement a QM system, in other words it describes a recipe for a QM system that comes at reasonable cost and in reasonable time.

Ingredient 1: Responsibility of Management

It is simple, but is very often neglected: The most important ingredient to set up a QM system is full management commitment and continuous support. Management must be 100% behind the QM system, or else it will not work. “Lip service” is not enough, real actions from the management to strengthen the position of the QM manager and commitment of the needed resources are an absolute must!  According to the literature, one of the most frequent reasons for QM system that do not result in economic benefits is lack of support from top management.1)

In the context of the PV industry, top management must rationalize and communicate the need for uncompromising QM in spite of enormous cost pressures. Delivering mediocre quality in the medium and long term will cause enormous economic damage in a competitive environment in which customers become more and more conscious that the product they buy as a long term investment must be from a reliable supplier who will deliver reliable products.

Incidentally, the ISO 9001 and the ISO TS 16949 standards for QM systems devote an entire section (= clause 5) to the responsibility of management. The author has practical experience both positive and negative (in different enterprises), thus “real life evidence” how important management commitment is.

Ingredient 2: Know and control your processes

To make quality means STABLE processes. Any development, manufacturing, measurement or administrative process must be under control. Standard operating procedures are a prerequisite for stable processes, and it can be assumed that in a reasonably managed enterprise, these are in place.

However, according to personal experience, professional management of the process by using statistical process control (SPC) is not as common as it should be. If processes are adjusted to center the process without using the criteria derived from SPC control, the process variation will get larger by a factor of 2 rather than smaller.

In the PV industry, the process variation and the resulting cell parameter variation is currently so large that binning of cells is absolutely necessary. Cells from one bin only should be used for one module to avoid excessive mismatch losses due to the variation of the cell parameters. Here the PV industry is at a state of process (im-)maturity where the microelectronics industry was in the 1970s. So there is ample room for improvement, and to propel and support continuous improvement is one of the central objectives of a QM system, ultimately to ensure dependable product quality.

Another critical issue is how to change a process (to increase e.g. the electric conversion efficiency and/or the productivity) without the risk of actually making things worse. Stable processes with known process variations are obviously a pre-requisite for continuous and rapid improvement of the processes and the product. The methodology of process change will also be subject of ingredient 5.

Ingredient 3: Manage your suppliers’ quality

In the PV industry, as in most other industries, cost pressures from customers are passed on to the material suppliers. It has been found that the most frequent cause of degradation in PV modules is either caused by the back sheet or the lamination material, resulting in delamination, browning and worst, water penetration. Also, micro cracks in cells are a frequent cause for performance degradation.

So, what is clear that the quality of the supplied materials has a direct impact on the quality of the PV modules. If a QM system is operative, the quality of the supplied material has to be ensured by a number of activities:

  • Outgoing inspection at the supplier and incoming inspection at the cell / module manufacturer are not an efficient way to ensure the quality, and there can be a significant slip of poor material since inspection has to be on a sampling basis.
  • The better strategy is to establish a supplier management, which ensures that a QM system is in place and its effectiveness is checked by so-called second party audits by QM experts from the own company.
  • The best way to ensure the quality of the supplier is to have direct access to the suppliers SPC data base, which is not uncommon in the microelectronics industry.
  • Equally important: the supplier must have a change and a deviation management in place, as described in ingredient 5.

Ingredient 4: Get buy-in from every employee

ISO 9001 and ISO TS 16949 are almost 100% technocratic and neglect a very important aspect: The human factor.

No technical QM system can be effective without the buy-in from every employee on the shop floor. This is, where communication from top management is a pre-requisite, but the details of what QM means in everyday production must be understood by engineers and foremen in the first place, and they must make sure to teach the shop floor employee the essentials of the QM system with respect to the details which are important for his/her workplace.

If continuous improvement is to happen, the contribution from employees of all levels is essential. Those companies which run successful employee suggestion schemes and self-managed groups benefit much more from a QM system than companies that do not place emphasis on involving there employees in the continuous improvement and QM processes.

Ingredient 5: Measure and improve

It is almost trivial: without a precise measurement of the performance of a process with respect to process variability and cost, no effective improvement activities are possible, since if the standard process (process of record) and the new process are compared, the standard deviation of the measured performance parameters (such as the average power of a PV module) must be smaller than the difference between the old and the new process. Since most process improvements are incremental and not “ground breaking”, a small process variability makes process improvement much easier and faster.

Another important aspect of process improvement is how to manage the change. Once a process has been qualified by certification and subsequent good field results for PV modules are obtained, the process is “frozen” and documented in the process of record. Any change however promising bears the risk of an unintentional deterioration of some sort. The worst that can happen is a reliability risk. However, if improvements are going to happen, the frozen process must be “unfrozen” in a controlled manner, in a well-structured change management process.

As an example, the change from supplier A of the back sheet to supplier B, who offers a lower price, is considered. To avoid the risk of poor reliability and durability degradation, a structured change management process must be adhered to, else the risk is simply too high.

The details of a state-of-the art change management process will be explained in a later publication of this series.

What is often neglected is the fact that in addition to intentional process changes to hopefully improve the manufacturing process or lower the cost, there are sometimes unintentional process changes = deviations from the process of record, either by equipment irregularities, or human errors, or other things that have gone wrong.

The effective management of such incidents without compromising quality requires a deviation management process, which is another tool out of the QM tool box (SPC, change management and audits have already been mentioned).

One important aspect of the deviation process is often neglected: It constitutes and important idea source for improvements! This will happen, if the problem that has surfaced is not just “repaired” but that the root cause is found and suitable measures implemented to prevent recurrence.

The “cooking”: How to turn the ingredients into QM System

All the ingredients have been prepared, so what does it take to turn the ingredients into a functional system. The answer is:

All processes

  • Development, production and logistic/administrative processes = ingredient 2 
  • procurement of materials and equipment = ingredient 3
  • a committed workforce (ingredient 4)
  • continuous improvement via change management and deviation management (ingredient 5)
  • the management review (part of ingredient 1, where management critically examines the performance of the processes and the QM system, which should lead to a further improvement of the company strategy and QM system)

must be subjected to  feedback ( = control ) loops, which in quality management are called the PDCA cycles (Plan, Do, Check, Act {learn from differences between objective and outcome)}.

In other words, a functional QM system is a system of feedback loops very similar to a living organism which is able to adapt to the challenges of the environment and which is able to elevated itself in the long run.

This is idea is visualized in figure 1: Once the QM system is functional, the typical firefighting mode to run a company is replaced by a continuous improvement of the quality and the business results.

with a QM

Fig. 1: Visualization of the positive impact of a quality management system on the quality of the product and ultimately the competitiveness of the enterprise

Final word

Admittedly, the recipe to set up a QM system is may be a slight oversimplification. All the same my message is clear: There is nothing mysterious or sophisticated about setting up a QM system. If done in a pragmatic way, the extra cost will be far overcompensated by cost savings and improvements in competiveness as a result of an effective quality management.

So it is no problem to set up a QM system, if suitable information material (or external help) is obtained. At any rate, it is advisable to consult the ISO 9001 and the ISO 9004 standards, which are like legal texts: sometimes difficult to read but full of useful information.

References:

1) M Terziovski, D Power, AS Sohal - European Journal of Operational Research, 146 2003, pp. 580-595

2) http://www.iso.org/iso/catalogue_detail?csnumber=46486

SEMI
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Grid
March 18, 2015