Performance Test Methodology for a 5-Axis Machining Center

Many manufacturing companies nowadays spend lots of money in buying expensive machine tools in the hope that these machines will help them to improve the quality and delivery of products they produced. With this heavy investment, the users expect the machine tools they purchased to have high performance in term of machining accuracy. One recommended method that they can use to verify machine tools accuracy is by conducting a performance test. The objective of this paper is to recommend an appropriate methodology of conducting a performance test on the machine tools upon delivery to the users. The performance test procedures should be based on certain standard such as ISO to ensure its validity. This paper also aims to educate the industrialists and machine users on the necessity of conducting their own machine performance test to ensure that they get good return in terms of machine performance from their heavy investment in machine tools. In this paper, the experiment of conducting performance test on a CNC 5-axis machining center in the Universiti Teknologi Petronas (UTP) is clearly outlined. The test conducted is based on the standard procedures specified in ISO 10791-2:2001: Test Conditions for Machining Centers „Geometric tests for machines with vertical spindle or universal heads with vertical primary rotary axis (vertical Z-axis)‟. In this test a standard test piece was machined using the machining center and certain critical parameters such as straightness, parallelism, angularity, perpendicularity, circularity, concentricity, position and cylindricity were then measured using Coordinate Measuring Machine (CMM). The results obtained were then compared to the ISO 10791-2:2001 standard. The experimental results showed that all the parameters measured were within the tolerances specified indicating that the machining center is operating in the acceptable working conditions. It is hoped that the experience gained at UTP would be beneficial to the machine tool industry and users at large.