The Application Study In Improvement Of Injection Molding Shrinkage Based On DMAIC

Since the costumer wants electronic products have better appearance and better mechanical behaviors, the key for Enterprise development focus on qualities sustainable improve。Injection product's quality depends on diverse factors, use some way to find the vital factor is a important issue for company to study.The thesis firstly introduce the importance of shrinkage, then it introduces the mainly used methods and influence factors. In the background of company introduced Six sigma into work, we used methods of DMAIC to improve the quality of injection molding.The study follows the DMAIC steps to analyze and control all the project. We analyze our plastic product, use Plato Diagram to find the critical factor which is shrinkage. Then define shrinkage is our aim to improve. we use GR&R to confirm our measurement system is under control. we measure mold and product dimensions to analyze the actual shrinkage of mold, find it different with suggestion or experience. Then use Minitab soft to analyze the pattern of actual shrinkage, and get the value we want to define the shrinkage of next mold which has similar structure. After this mold is made, study the quality of its product, analyze if it has some improve, the result is made.At last, give a logical way to define shrinkage base on experiments which did before mold is designed, and make standardization process. So it gives a reference method to define shrinkage.