Process improvement in Zamak injection machines for automotive component fabrication

Abstract

Die casting processes are nowadays widely used in the industry and differentiate from metal casting from the high-speed and pressure applied to inject the metal into the cavity. Due to this procedure, the produced parts manage to acquire better mechanical characteristics, dimensional precision, and smaller roughness. Due to the automation possibility, and mould coating possibilities, the process becomes cost competitive at significant production rates. However, to assure proper functioning and extended life of die casting equipment, it is necessary to continuously control the process variables, undertake maintenance, and implement process improvement actions to the production lines. The objective of the present work is to improve the efficiency of a Zamak die cast injection line for cable terminals used in Bowden or control cables for the automotive industry. By reducing wear and number of failures of standard components in this production line, and thus by diminishing the stoppage and replacement costs, it becomes possible to improve the current process. By applying specific improvements to the injection subset, heating element, and pump, including geometry modifications to the injection elements and respective interactions, heat treatments, higher power resistor, and groove/ring system in the pumps’ piston, a significant process improvement was accomplished by the proposed and tested modifications, leading to reduction of failures and operational costs, and consequently higher competitiveness of the process.