In the production of stainless steel casting process have the biggest problem is the casting shrinkage defects, in order to solve this problem, many experts research, now solve for casting shrinkage defects summarized the following points: 1, changes the location within the casting runner. 2, reasonable process design. Nene runner runner located in Pu cast opposite wall, and dispersed more hours. So that the first to enter the thick lead at the solidification of liquid metal, solidified thin wall, so the entire basic equilibrium solidification. Casting machine for uniform wall thickness, using multiple ingate and vents. Ingate more decentralized and uniform, and the overall heat balance. Fine and many vents that exhaust unobstructed cooling effect was underway. 3, in the thickest section of the stainless steel and heat-formed casting structure, the implementation of rapid solidification, artificially created a basic balance throughout the casting temperature field. Inside and outside the cold iron, partial use heat storage capacity of zircon sand, chromite sand or special coatings.
Specializes in the design of the casting people know, the wall thickness of the stainless steel castings casting quality has a great influence, casting thick walls, the walls were too thin is not good, so in the design of die casting design wall thickness should be reasonable force Paul casting quality is not affected by the thickness aspect from. In aluminum die casting, for example, under normal circumstances, have higher strength and thin wall better than the thick dense casting, in view of this, stainless steel castings design should follow this principle: to ensure sufficient strength castings and rigid premise should be to minimize the thickness and maintain uniformity in wall thickness. Practice has proved that the wall thickness of casting design generally 2.5-4mm appropriate, the wall thickness of the part should not be used more than 6mm die-casting production process. Casting wall is too thick, thin wall castings quality performance effects: If the design of the casting wall is too thin, make good metal welding, casting a direct impact strength, while forming would cause difficulties; the walls are too thick or severe uneven prone deflated and cracks, on the other hand, with the increase in wall thickness, casting internal porosity, shrinkage and other defects also increase, it will also reduce the casting strength, influence casting quality. |