Do you know what are the common problems in the use of coated sand production line

Due to the need for the export of casting products and the rapid development of China's industry. The technology of coated sand production line in China has developed rapidly and its application has become more and more extensive. What are the common problems in the use of coated sand production line:

Type 1 (core) surface is loose: the core injection pressure is too high or too low, the mold exhaust is not smooth, the mold runs sand due to the large gap between the sub-box surface, and the molding sand of the coated sand production line has poor fluidity or poor air permeability.

Choose reasonable sand injection pressure, improve the exhaust system, prevent suffocation, use small deformation of the material as the core box, choose good fluidity and permeability of coated sand.

Type 2 (core) deformation, fracture mold heating is not uniform, or the core wall thickness difference is large, resulting in inconsistent shrinkage during cooling.

The resin with large curing shrinkage is adopted, the core receiving fork is deformed or the sand core is stored unevenly, the high temperature performance of the coated sand is poor, the pouring pressure is too large to improve the mold structure and make the temperature distribution uniform, the sand core is stored in the molding tray, the resin with small curing shrinkage is adopted, the coated sand with high temperature resistance and low expansion is adopted, and the improved pouring system adopts pressureless type.

3 The air hole core of the casting is not exhausted smoothly, the amount of gas produced by the resin sand is large or the gas production speed is inappropriate, and the sand core is not completely cured.

Improve the exhaust system, improve the exhaust effect, choose high concentration or coarse raw sand; use low gas coating sand.

4 The resin in the casting internal shrinkage coated sand equipment burns at high temperature to generate heat, which slows down the solidification rate of molten iron and leads to shrinkage.

Chilled coated sand is used, and internal chilled iron is placed in the shell core.

5 shelling: the mold design is unreasonable, the temperature of the core box is uneven, so that the strength of the low temperature part is low and shelling, the melting point of the coated sand is low, the curing speed is slow, and the thermal strength is low.

Improve the mold structure, so that the temperature distribution is uniform, the selection of high melting point, fast curing speed, high thermal strength of the resin.

This article is finished by coated sand, the point of view of this article does not represent the point of view of this site.