Core sand mixing process, heated core box core-making process and sand core prepared therefrom

Abstract

The invention provides a core sand mixing process, comprising the following steps of: (a) mixing ceramic sand and calcined sand according to the weight proportion of 4:6-6:4; and (b) primarily mixing the ceramic sand and the calcined sand for 20-30s, adding a curing agent into a mixture of the ceramic sand and the calcined sand, mixing for 50-60s, then adding heated core box resin, and mixing for 120-150s, wherein the addition amount of the heated core box resin accounts for 1.8-2.5% of the total weight of the ceramic sand and the calcined sand, and the weight of the curing agent accounts for 20-30% of that of the heated core box resin. The invention further provides a heated core box core-making process comprising the core sand mixing process. In the core sand mixing process, the ceramic sand and the calcined sand are adopted as raw sand, less abrasion is generated in a core making process, and the demoulding performance of sand cores is good; the consumption amount of the resin is lower so that more resin are saved and the cost is low; the sand cores of the ceramic sand and the calcined sand have good collapsibility and the cavity quality of a produced casting is better; and the ceramic sand resources are more sufficient.

Description

technical field [0001] The invention relates to the field of casting, in particular to a core sand mixing process, a hot core box core making process and a sand core prepared therefrom. Background technique [0002] The hot core box sand core making process is a method of machine-made sand cores in foundry production. The sand material mixed with foundry sand, thermosetting resin and catalyst is injected into a core box with a heating device and heated to 180 ° C ~ 250°C, heat the sand close to the surface of the core box, under the action of temperature, its binder can be condensed and hardened in a short time to form a sand core, which does not need to be dried in an oven, which shortens the production cycle Etc. Moreover, as long as the surface layer of the sand core has a millimeter to form a hard shell, it can be taken out from the core box, and the sand core in the central part can be hardened by itself by using the waste heat and the heat released by the hardening re...

AI Technical Summary

Problems solved by technology

This process can stably and reliably produce dry-type cylinder liner cylinder block water jacket cores with a length of about 1m. However, the chrome ore is crushed from natural chrome ore, and the shape is sharp-edged particles. After long-term use, the chrome ore will wear the mold more Big

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