Kunming Iron And Steel Sintering Grate Production Quality Management Research

The quality is enterprise's life. The product quality is influenced by many factors such as production and management in enterprise. It is comprehensive behavior of every working procedure and is already the core of modern business management. At present, the quantity of steel in our country is in the first place of the world. The bar grate is a very important component for the sintering equipment in the metallurgical industry and it is also vulnerable. The working condition is abominable, so it costs more bar grates. The annual yield of steel is four million tons and the consumption of the bar grate is reach to one hundred tons in Kunming Iron & Steel co. Ltd. (KISC). As a result, reducing cost must control the production quality of bar grate , which is very valuable.Nowadays, the internal factories used two ways, which are sand mold and lost foam casting. From 1997 to 2000 year, KISC used sand mold, which produced the bar, grate of high-Cr cast iron. It produced some defects in the process of casting, such as swelling sand, pore, shrinkage cavity, porosity and crack. These defects influenced product strength and quality. The casting chemical compositions are subject to variation. It reduced product quality and Service Life. From 2001 to today, KISC use lost foam, which produced the bar, grate of high-Cr cast iron in sintering factory and casting defects are reduced. But there are some other defects of lost foam casting, which need to be improved in future. The enterprise hopes to attain improvement and method, which are used to improve the bar, grate quality in a hurry.Based on actual situation in the bar grate of sintering machine of casting production, the paper discusses the theory of high chromium cast iron production process and management. Aimed at the bar grate of 130 m2 and the method of lost foam casting, the influence of product quality and reasons are analyzed by Pareto and Cause and Effect Diagram. And aimed at three principal causes are analyzed, which are the defect for sinking frunk, pore and shrinkage cavity. According to the theory and methods of casting quality management, advanced improvement and method of bar grate, then the research results are applied in actual production. Reduced the rate of rejects from 5.9% to 1.9% and improved product quality. Reduced the waste of the immediate rejects, which is more than 30 thousands Yuan. It achieved good economic efficiency.