Shrinkage is an enemy of metal coat hooks processors are facing, especially for high surface quality requirement of large metal clothing products, shrinkage is a problem.
So people have developed a variety of techniques to minimize shrinkage and improve the quality of products.
In injection molding metal parts thicker clothes hook position, such as reinforced rib or bumps in the formation of shrinkage is more serious than adjacent location, this is due to the thicker area of cooling speed is much slower than the surrounding area.
Different cooling rate leads to the formation of a junction surface of sag, namely into the shrinkage mark.
This defect seriously limits the metal clothing product design and molding, especially the large thick wall products such as TV chassis and cant display shell, etc.
Strict for household electrical appliances, in fact, this kind of products must eliminate shrinkage mark, for toys such as the product with high surface quality requirement is not allowed to have the existence of the shrinkage mark.