Cold core

Abstract

The invention relates to a coil core, which comprises sand core main body. Wherein, it is formed by upper and lower cores whose edges are compressed; the sand core has chamber with dual connecting posts fixed with upper and lower cores; the thickness of main body is 10-60mm. And the production comprises that producing upper and lower cores whose connecting surfaces relative to the connecting post are lower than side wall, and central has through hole; the upper and lower cores are opposite, to align their through holes; compressing upper and lower cores, to connect their through holes to form connecting posts. The invention can obtain hollow sand core main body, to confirm support strength, and avoid crack.

Description

technical field [0001] The invention relates to a sand core used in casting molding, in particular to the improvement of the structure of the cold core sand core and its manufacturing method. Background technique [0002] The sand cores used in the foundry industry can be divided into hot cores and cold cores according to the different manufacturing processes. The hot core is to harden the core sand in the core box by heating the core box. However, during the production process, the core box It is easy to deform due to heat, which will affect the shape and size of the sand core; while the cold core is made by mixing the core sand with the binder resin and then adding a curing agent to make it harden at a temperature below 80 ° C. According to the curing agent The difference is divided into triethylamine method, sulfur dioxide method, β method, etc. Taking triethylamine method as an example, the basic process method is: ① put the core sand mixed wi...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a cold core with improved structure, which solves the problems of cracking, seams and poor combination of core and support in the prior art when making large-size castings

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