INVESTIGATING THE OPTIMUM COLD FORGING PROCESSES CASE STUDY ON THE CARBON STEEL HEX BOLT M8x25

• Main Authors: Thanh – Nghi Ngo, 吳清毅
• Other Authors: Yung – Chou Kao
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/68501367134598943598

碩士 === 國立高雄應用科技大學 === 精密模具與機械產研碩士外國專班 === 99 === ABSTRACT Cold forging process can be described as the process where a metal is plastically deformed at room temperature with application of huge pressure. The process not only changes the shape but also improves the properties of the forged parts. In cold forging process, forming load is one of the most important factors. It affects mechanical durability as well as fatigue life of die. Forming load is expected as low as possible. This study will investigate the design of cold forging die for hex bolt M8x25. DEFORM 3D software and Taguchi method was used to optimize forming load by changing some design parameters. The simulation was carried out with an orthogonal array (L9) based on the Taguchi method. The results showed that the optimal values of parameters are rake angle in process 2 at level 1 (1o), across flats distance in process 2 at level 1 (12.7 mm), draft angle in process 2 at level 1 (25o) and rake angle in process 3 at level 3 (3o). After optimizing, the optimized parameters reduced the forming load of top die in process 3 by 26.6% (5.13x104N comparison with initial value 6.99x104N).