Six Sigma and SPC tools

Improving customer satisfaction through Six Sigma

and other TQM/SPC tools

Six Sigma has been described as “a highly technical method using by engineers and staticians to fine-product and processes” Cavanagah, R.R. and others (2000) or “it’s a goal of near perfection in meeting customer’s requirements” Both parts are right in some aspects, more and more in the statistics bit. Six Sigma is an statisctic target. In companies where Six Sigma has been pursued and achieved, like General Electric or Motorola they agree that Six Sigma is more a change of culture.

Six Sigma is based in two interconnected factors: “total customer satisfaction and effective and efficient internal process”. The success of a company depends on the ability of satisfying customer’s quickly changing needs and how well the internal work is managed for coping with this changing demand. The ability of a succesful company for changing is not given by quick or risky decissions. It starts with the identification of the company’s key processes and manages them for being under control. Six Sigma is only a method to gain competitive advantage. Lowenthal, J.(1958 )

The Voice of the Customer is very important in the Six Sigma methodology. The voice of the process is the second area of interest. Six Sigma companies must listen to both voices. The one that speaks from outside the company, and he one that speaks for the company and for the product, the process. Only by listenting both, changes can be made to the process that satisfies the customer demands. Lowenthal, J.(1958 )

The fusion of Six Sigma an Lean Manufacturing is necessay because:

• Lean itself can not bring a process under statistical control.
• Six Sigma can not make a process faster or reduce it’s cost.

That’s why quality problems manifest themselves as scrap, waste or “muda”. A small amout of this waste can reduce the productivity of a factory a lot. The principle of Lean Six Sigma says: “The activities that cause the customer’s Critical to Quality issues and create the longest Time Delays in any process offer the greatest opportunity for improving in Cost, Quality, and Lead time”. Lean Six Sigma pretends to improve quality and customer satisfaction by  reducing lack time, cost and a rapid response to the changing customer’s needs. George, L.M. (2002)

SPC

Statistical Process Control is based in the adquisition and analysis of data. Decisions are taken based in these data analysis. But the implementation of Six Sigma goes further. Is also accepted that many decissions inside companies are based in opinions and assumptions. Six Sigma reduces this random and unclear decissions by presenting two questions:

1.       What data do I really need?

2.       What do I do/analize/use this data for obtaining maximum benefit?

Using DMAIC

DMAIC is a structured problem-solving methodology widely used in business. The letters are an acronym for the five phases of Six Sigma improvement: Define-Measure-Analyze-Improve-Control. This strategy encourages creative thinking and aproves ideas like keeping the basic products, process and services.

• • Define- Define the team, and reach an agreement on the scoop, goals and boundaries
  • Measure-Understand and collect data from the process, speed, quality, costs. This information will be used to expose causes of problems.
  • Analyze- Here is where DMAIC comes to statistics, in this phase, the key inputs and outputs of the process have to be monitorised (The critical Xs). And perform data analysis.
  • Improve- Generate potential solutions. Prioritise and implement them, applying Six Sigma lean manufacturing best practises.
  • Control- Document standard procedures and set process control plans that permit maintain the gains

George. L et al (2005)

Using DFSS

“Is all about improving the peformance of your organization by using a structured approach for minimizing the mistakes and waste in all process” After the success of Motorola, Honeywell and GE, Six Sigma is the most popular process improving philosophy. Dr Shewart invented control charts in the early 20s and dr. Deming the Plan-Do-Check-Act problem solving strategy soon after WWII. Six Sigma concepts are invented since nearly a century. So what is new? DFSS (Design For Six Sigma) prevents future problems from appear, while DMAIC solves current problems. DFSS guarantees good products even when the key process changes. DFSS focuses in the design and development of new products and processes by selecting Critical to Quality characteristics (CTQ’s). Champions, Black Belts and Green Belts are the spine of this strategy.

Roadmap PIDOV:

• • Plan: Develope goals and metrics. Specify stakeholders and risks.
  • Identify: Identify the product concept that best satisfies the VOC.
  • Design: Design the new product and process. In this step statistics are vital to predict future performance
  • Optimize: Achieve balance between quality and cost
  • Validate: Verify the preditions from early phases and the customer requirements

Sleeper, A. (2006)

The inmediate goal of Six Sigma is the reduction in number of defect, and provide the necessary control tools to drive the process under control. Reduced defects lead to product improvement, and product improvement provides customer satisfaction. Defect reduction is intended to lead to cost reduction. It has a process focus, and aims to highlight process improvement oportunities under continuous measurements.

Some arguments agains Six Sigma is that quality needs to be created, not just monitored. That stays in line with Taguchi philosophy “quality has to be embuilt in the product, not inspected into it” Stamatis (2000)

Some companies such as Clarke American have decided not to go for the Six Sigma way. They intend to have better quality improvement systems oriented in the customer satisfactin and the employers involvement.  Raisinghani, M.S. (2005)

Merck, the US pharmaceuticals company is using six sigma in redefining the R&D, finance and marketing departments. His chief executive, Dick Clark says in an interview for Financial Times on March 2006: “We got Six Sigma and black belts now working in marketing and sales…We’re finding out we can be a heck of a lot more effective than we ever were before. And so we can do a lot more with less”

ISO 9000:2000 should we go ahead?

Quality control is a process for maintaining Standards, but it doesn’t create them. It allows selection, measurement and correction of work, and prevents undesirable changes in the quality of the product. Some failures are not allowed to appear, so they must be prevented from happening through proper planning and design.

“There are several benefits to be gained from installing a quality system that meets ISO 9000…The ISO 9000 model of a quality system is built upon the principle of preventing nonconformity at all stages in the supply chain. If the right tasks are carried out right first time, then there will be no waste, costs will be at a minimum and profit a maximum. Profit is always the result of what you do so by reducing error, remedial action and waste, you save time, resources and materials and maximizes profits” Hoyle, D (1994)

There are several benefits in ISO 9000, as are mentioned in Hoyle, D (1994):

· Free management of intervention in the operations of the business, and giving the staff the means to control their own work/operations and performance.

· Identify the key tasks and specify how they should be faced for obtaining right results.

· Provide ways of planning these tasks in advance and set procedures for completing them.

· Provide the appropriate resources and training to the people, so that they can perform their tasks right

· Implementation of statistical tools that permit control and measurement for identifying problems and preventing their recurrence.

· Provide objective evidence that can be used to demonstrate the quality of your products and services and to demonstrate that your operations are under control.

· Increase net profit and reduction in costs, allowing the company to control risks and loses associated with defective products

Some elemental benefits of acquiring a quality system in the company are also there. Have the permit to advertise that the company has been registered with ISO 9000 and boost the marketing profile. The capability of the company for signing contracts only let to ISO 9000 registered organizations. As Barnes, F. mentions in his paper ISO 9000 myth and reality, reduced costs and quality improvement were the reasons for less than a quarter of the companies applying for ISO 9000 certification. One in 10 was driven by international issues.

There are also some problems or unhappy attitudes towards ISO 9000. Some arguments are that it focuses too much in the company and not enough on its costumers and that the directives are too general and fail to address the problems and issues correspondent to particular industries Barnes, F (1998). Other arguments are that quality by inspection is not quality, because increases errors, and undermines the moral of the workers, and that the standard relies too much in people and assessors interpretations of quality. Seddon, J. (1997)

Dale, G.B. mentions some other difficulties, like restrictions in creativity, high cost in application of ISO 9000 (documentation and training for staff may consume time, resources and budget), lack of relevance to the real needs of the customer, and the necessary bureaucracy involved is perceived as a barrier to provide results and flexible servide.

Get ISO 9000:2000 and have a look through these aspects.