The tool path optimization is an important issue to get a low cost of manufacture parts using the CNC (Computer Numerical Control) machines. Programming to produce an optimum tool path for CNC machines is a key performance indicator for obtaining minimized machining time and good surface quality of parts. This paper purposes to optimized the CNC tool path generation programming and analyze the cost of manufacturing process of master cylinder piston of motorcycle brake. A Computer Aided Manufacturing (CAM) software was used to simulate an optimal tool path, which finding an efficient solution to shorten the cutting tool path generation. The simulation was performed on a roughing surface process of the work piece using 3 tool path schemes: longitudinal, diametrical and surface to parallel. The each scheme employed tool-path generation based on absolute and incremental reference methods of a CNC lathe machine. An analysis of simulation tool path time for each scheme and machining cost was investigated to get optimum and economies machining process. Hence, it was compared to actual time of machining process on CNC lathe in term of the manufacturing cost machining. The optimal processing time and the most economical cost for making a master cylinder piston of motorcycle brake was a parallel to surface scheme. Therefore, an optimization of tool path generation can minimize machining lead time, which lead to lowest cost of manufacturing parts, with keep maintain product quality.
Department of Mechanical Engineering, Universitas Riau, Indonesia
A new shape of stop-drilled hole is proposed in which triple stop-drilled holes called Multi Stop Drilled Hole (MSDH) are drilling at the crack tip. The main objective of the proposing method is to reduce stress concentration at the edge of the stop holes. Reducing the stress concentration factor at the crack tip is the main issue to arrest the crack growth. In this study, a numerical methodology using finite element analysis with linear elastic behaviour assumption is considered to study the effect of the stop-drilled hole on the reduction of stress concentration at crack tip. The variation number of stop-drilled hole and hole diameter at the crack tip corresponding to the stress concentration will be investigated. It reveals that the number of stop-drilled holes significantly influenced to reduce the stress concentration factor. Increasing the number of the stop-drilled holes will reduce the stress concentration factor. Furthermore, the diameter of stop hole significantly affects the decreasing stress concentration. The increasing value diameter of the stop-drilled hole will reduce the stress concentration. In the meantime, the triple-drilled hole has the highest percentages of decreasing stress concentration and the lowest stress concentration comparing to single and double stop-drilled hole.
Department of Mechanical Engineering, Faculty of Engineering, Universitas Andalas Padang, 25163 Sumatera Barat, Indonesia
