| Multi-way valve is the core component of the loader, which is one of the most demanding parts in manufacturing accuracy in the whole machine. Its failure often leads to a direct stop of the machine. So, it becomes very urgent to improve its reliability. And with the increasing requirements in control and comfort of the machine, users put forward higher expectations in the performance of multi-way valve. Based on the current quality status of mechanical control multi-way valve which has been mass used in China, by using the Six Sigma quality tool, and under the premise of no increase of the cost, this paper systematically summarizes the current existing problems of the multi-way valve in detail design and machining processes, makes research, exploration and optimization in local performance improvement, machining technology research and quality control model establishment. With a result, Lingong’s mechanical control multi-way valve in 5-ton loaders has been significantly improved in quality.The main contents of this paper include two aspects:(1) By using six sigma tool, in accordance with steps of D (define), M (measure), A (improve), I (analyze) and C (control), and combining the application of various quality statistical analysis methods, to systematically summarize the failure modes of the multi-way valve in different time. Through the application of MSA (measurement system analysis), process capability research, flow chart, C & E matrix, and FMEA to summarize and assess the detail design structure of the multi-way valve and process elements of Lingong’s golden supplier of A company, and to find out the breakthrough point of improving the quality of multi-way valve. and test through factor analysis and DOE (design of experiments), etc., obtained the suitable production status of the optimal processing parameters for, and curing to processing, to achieve a multi way valve part structure design improvement and production process capability improvement.(2) By using the key factor of multi way valve production process in the process of system identification, monitoring, improve and refine the quantitative indicators of the key elements of the process of evaluation, establishes the Lingong the multi way valve manufacturing process quality control model and the quality control of this model is extended to other key purchased parts, for the establishment of the quality control model of production status of temporary workers, to achieve a breakthrough in Lingong foreign purchase parts quality control method. |
