Achieving Customer Specifications Through Process Improvement Using Six Sigma: Case Study of NutriSoil – Portugal

Abstract

Tolerance limits are essential in production process management, as they determine consumer satisfaction. The use of statistical quality control tools allows for process improvement and the c_pk index enables its measurement. Above all, the adoption by businesses of lean tools has been crucial in reducing the variation of a process or a product, satisfying the consumer's specifications, eliminating defects, reducing operating costs, and, in short, increasing profitability.

The NutriSoil Company in Portugal, a small and medium-sized enterprise (SME), sells fertilizer in bags. The company has had problems with its filling process due to excess weight of the bags. Results show that by implementing Six Sigma combined with the 5S program, NutriSoil achieved an improvement in its c_pk index for this process, which increased consumer satisfaction and a highly significant cost savings. This resulted in increased competitiveness.

• c_p and c_pk capability index
• process capability
• process improvement
• Six Sigma
• SME
• statistical quality control

Additional information

Notes on contributors

Amândio Pereira Baýa

Amândio Pereira Baía is a professor in the management department at Guarda Polytechnic. He has a master's degree in industrial management from Clemson University, and a doctorate in statistics and operational research from Coventry University in England. He can be reached by email at [email protected].