Abstract
Constantly improving, which is one of the principles of quality management is the base for good understanding, behaviour of individual processes, investigating variability and impact on its the process. The aim of every business is to increase profits. Reducing the cost of tools can also contribute to this. Utilising the DOE method to reduce the durability of removable cutting plate, as describe the article, is one of way, how to apply this method in practice. The DOE method enables find factors that are the most relevant to the production process and determine their best values. Using this method, you can set the selected inputs so that, the process achieves the desired results with maximum stability and resilience. The article contains a brief overview of Minitab software by which the collected process data was analysed. The core of the article describes how to solve the problem using the singular phases of the DMAIC cycle. Each of these phases has its own specific aim, which logically defines what activities each step is aimed at. DMAIC is extended variant of the process improvement model based at the Deming circle PDCA. Six sigma methodology is used as a standard procedure for project planning and realisation. At the end of an article is described that by increase durability of removable cutting plate the problems found in the analysis of the current condition that have been validated by a case study in the company have been eliminated.