Design and development of a competitive wire splicing system for the automotive wire harness industry : a thesis presented in partial fulfilment of the requirements for the Master of Technology in Manufacturing and Industrial Technology at Massey University, Palmerston North, New Zealand
The work presented in this thesis is aimed at developing a very comprehensive system of manufacturing wire splices for automobile wire harnesses. Ultrasonic welding is increasingly being used in various industrial applications. Lack of a scientific data-base of its properties when applied to wire splicing is a major reason for lack of proper usage by the wiring harness industry and its subsequent acceptance by the end user. This thesis presents various experiments conducted to develop tensile strengths and electrical resistances of various types of ultrasonically welded wire splices. Crimping technology was evaluated for its mechanical strengths and electrical properties by conducting various experiments to make it possible for the industry to compare it with other alternative splicing technologies. The results are then compared with ultrasonic welding. The next stage of this thesis discusses the economic feasibility of ultrasonic wire splicing. In order to find the number of ultrasonic welding machines required to meet a particular level of demand, which is a prerequisite for establishing the economic feasibility, a virtual model of the process and the manufacturing cell has been prepared and this model was used to study the dynamics of demand and the number of required machines. Simulation in manufacturing-problem-solving is being used very widely by researchers. Proper understanding and visualisation of the future of the factory and understanding and answering various questions related to the adoption of new technology, is another major reason why companies shy away from adopting ultrasonic welding systems. An advanced simulation tool namely QUEST was used to model the wire splice manufacturing cell of Alcatel and simulation studies were conducted to foresee how the production dynamics would be if ultrasonic welding machines were incorporated in place of crimping machines and various what if scenarios were developed and some vital production related questions were answered. Material handling is a major bottleneck in any wiring harness manufacturing environment. Some conceptual designs are presented on automating the task of feeding wires to ultrasonic welding machines and transferring the wire assemblies from welding stations to different work stations, currently being done manually. A wire palletising system was designed to improve the productivity. This thesis concludes that ultrasonic welding could be very effectively used for wire splicing and could be safely used in the manufacture of wiring harnesses for the automobile industry.