Surface sulfur seepage prevention coating for furan resin-sand production wind power nodular iron casting

Abstract

The invention provides surface sulfur seepage prevention coating for a furan resin-sand production wind power nodular iron casting. The surface sulfur seepage prevention coating is prepared from the following components in parts by weight: 62 to 70 parts of magnesia powder, 2 to 3 parts of lithium-based bentonite, 1 to 1.5 parts of organic bentonite, 0.8 to 1.5 parts of phenolic resin, 0.5 to 1 part of industrial glucose, 0.2 part of polyvinyl butyral (PVB), 0.5 to 1 part of rosin, 0.15 part of ethyl silicate and 24 to 30 parts of ethyl alcohol. The surface sulfur seepage prevention coating of the technical scheme disclosed by the invention can be used for production of all the furan resin-sand production wind power nodular iron castings; for a common mechanical casting, the quality can be improved, and the wind power nodular iron casting and an outlet nodular iron casting can meet the technical requirement of a user more easily; and the surface layer, subjected to sanding cleaning, of the nodular iron casting does not have a sulfur seepage shortcoming, so that the loss on defective product is greatly reduced, and the surface sulfur seepage prevention coating is relatively high in practical value.

Description

technical field [0001] The invention belongs to the field of casting technology, and in particular relates to a surface anti-seepage sulfur coating for producing wind power ductile iron parts with furan resin sand. Background technique [0002] The principle of furan resin sand molding process is: add furan resin and curing agent to the molding sand and stir evenly, the resin and curing agent react to harden the molding sand to meet the strength requirements of pouring molten iron. The curing agent must be an acid liquid. The most economical and best curing agent is a sulfonic acid curing agent, and the sulfonic acid contains sulfur. The sulfur brought in) forms SO2 into the molten iron on the surface of the cavity, and SO2 reacts with magnesium (Mg) in the molten iron: Mg+SO2=MgO+MgS. The result of the reaction reduces the magnesium content in the molten iron on the surface of the casting, which is not enough to make the graphite ball It will eventually cause the surface l...

AI Technical Summary

Problems solved by technology

In order to eliminate the surface defects of castings, a small number of large-scale foundry enterprises in China have replaced more expensive resins with other types of resins, but this has greatly increased the cost of enterprises

The application number is 201110332130.1, and the name is "an anti-sulfur coating for casting surface of furan resin sand mold". There is 0.12-0.2%, such a small amount of magnesia is not enough to absorb sulfur from the molding sand; at the same time, between the interface between the hot molten iron and the sand mold at a temperature above 1300 degrees, the coating layer within 1mm is used for isolation, and its effect is very limited. Yes, and the sintering of the paint to form vitrification takes time, and it is impossible to form the molten iron immediately after pouring into the sand mold, so the practical effect of this patent is limited, and it cannot satisfy the production of ductile iron castings for wind power generation equipment at all. need, therefore it is necessary to propose improvements

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