Redesign Alat Las Gesek Rotari Dengan Pendekatan Fault Tree Analysis (FTA) Dan Design for Manufacture and Assembly (DFMA)

Abstract

The FTA is a method to identify the failure of system. Whilst, the DFMA is a method to determine how to design of product, which is purposed to increases the quality of product and make easily the product assembly process. The rotary friction welding is one of type of friction welding, that principle is both of surfaces by friction which one end is fixed and then provides axial pressure to against another the rotating surface until both surface forge together. The Rotary friction welding machine in Production Technology Laboratory, Department of Mechanical Engineering, Universitas Riau has some shortcoming, as sequences the welding results are not optimal. Furthermore, this research aims to overcome the deficiency rotary friction welding machine in the Mechanical Engineering, Universitas Riau, then identified the problems using the FTA method and redesign one using the DFMA method. There were several steps to conduct testing of the rotary friction welding i.e. before redesign, after redesign, and final testing, which was obtained a final better design. Result of testing indicated an average value of the vibration was reduced, on the x-axis was reduced from 15.34 mm /s to 15.44 mm /s, the y-axis of 20.04 mm /s to 17.94 mm /s, z axis of 28.58 mm /s to 18.58 mm /s. Then, the average maximum tensile strength of the welding specimen increased from 574.66 N/mm2 to 651.10 N/mm2, and the assembly efficiency increased from 3% to 5%. It can be concluded the redesign of rotary friction welding was better than before.
Keywords: FTA, DFMA, Rotary Friction Welding, Vibration, Tensile Strength,Assembly Efficiency.