Research Of The Quality Control Improvement Of Company S's Faucet Lead-removal Cleaning

It has been confirmed that the lead-exsitance in traditional brass faucets is harmful tohuman beings. Many areas and countries, especially Europe and Northern America, there arelegal requirements for the faucets and other plumbing parts in use, of that the amount of leaddissolved in water from faucet must be controlled.Company S is a specialized production of faucets and other plumbing parts, more than95% of its products sold in Europe and Northern America. There is a special process calledLead-removal to cope with the faucets'lead-dissolution in company S. In this process, achemical cleaning method has been used to make the selective dissolution of lead. In recentyears, Europe and the United States have tightened the relevant standards, and with thechanges, the productions of faucets become more and more difficult. In the past two years,company S's lead–removed parts have failed increasingly in the test. A scientific processoptimization and improvement is demanded to carry out.The research and improvement of lead-removal mainly through the following twodirections. First, using Robust Design Optimization of parameters to improve the ability androbustness of the lead-removal process; Second, to estimate the main effects and find out themore significant relatively factors, and to improve the control methods.The author has introduced some legal regulations on lead restrictions firstly, and thenelaborated about total quality management, principles and methods of robust design etc.At thenext, the author has analyzed the lead-removal test data of company S in the past 2 years,andfound out a obviously decline of lead-removal quality performance.In the third section, theauthor's used the robust design method, made two experiment to determine the main effect ofthe factors, and completed the optimization of key parameters; Finally, the study focused onthe optimized parameters's control and managemet in workshop. In the final, the optimizedparameters and control methods have been confirmed more effective than the old ones by aexperiment.