Precoated sand mixing process

Abstract

The invention provides a precoated sand mixing process which is characterized by comprising the following steps: (1) heating crude sand, adding the crude sand into a sand mixing machine after the temperature of the crude sand rises to 140 DEG C -160 DEG C, adding and mixing an adhesive with the sand, stirring for 1-2 minutes to obtain adhesive sand, and adding a deodorant while stirring in a stirring process; (2) adding a lubricant into the adhesive sand, mixing with the sand for 1-2 minutes, cooling down the adhesive sand after being mixed, adding a curing agent when the temperature of the adhesive sand is reduced to be 105-110 DEG C, and mixing for 20-40 seconds so as to obtain curing agent sand; and (3) adding the lubricant into the curing agent sand, mixing with the sand for 1-2 minutes, cooling down the curing agent sand after mixing, and discharging the sand when the temperature of the sand is reduced to be less than 70 DEG C so as to obtain precoated sand, wherein the addition amount of the adhesive is 1.5-2.5% of the total weight of the crude sand, the addition amount of the deodorant is 20-40% of the addition amount of the adhesive, the addition amount of the curing agent is 10-20% of the addition amount of the adhesive, and the addition amount of the lubricant is 2-6% of the addition amount of the adhesive. The precoated sand produced by using the precoated sand mixing process has the characteristics that the pungent smell is little, agglomeration is unlikely to happen, the roughness degree is low, and the sand is unlikely to adhere to a cast piece.

Description

technical field [0001] The invention relates to a core (mold) sand mixing process, in particular to a coating sand mixing process capable of reducing the peculiar smell of the coated sand, and belongs to the field of casting technology. Background technique [0002] Coated sand refers to the molding sand or core sand that is covered with a layer of solid resin on the surface of the sand before molding. It is widely used in foundry fields such as iron castings. [0003] The Chinese Patent Publication No. CN102921878A discloses a coated sand and its preparation method, which is made of the following raw materials by weight: 40 parts of 50-100 mesh calcined quartz sand, 40-70 mesh mullite high temperature 30 parts of calcined sand, 30 parts of 50-100 mesh chromite sand, 2 parts of phenolic resin, 0.3 part of curing agent, 1 part of additive, in the preparation method, add raw sand, adhesive, curing agent and additive in sequence , through sand unloading, crushing and screenin...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the deficiencies in the background technology, the purpose of the present invention is to overcome the defects of the background technology such as strong pungent odor, long-term storage in high-temperature an...