Special coating of hot-mould centrifugal casting mould for flexible joint ferrosteel pipe

Abstract

The present invention relates to a soft joint grey cast-iron pipe hot-mould centrifugal casting special-purpose adhering moulding material. It includes fire-resisting aggregate, bonding agent, suspension agent and water. The described fire-resisting aggregate includes diatomite powder, perlite powder, vermiculite powder and silica flour, and the described bonding agent and suspension agent include sodium base bentonite and sodium cellalose glycollate. Said invention also provides its preparation method and concrete steps.

Description

technical field [0001] The invention relates to a special paint and technology for hot mold centrifugal casting molds of gray cast iron pipes with flexible interfaces. Background technique [0002] Flexible interface gray cast iron pipe (DN50-DN300mm×3000mm) metal mold casting mold at 200 ~ 250 ℃, spray water-based refractory coating on the inner surface of the high-speed rotating mold, the water in the coating evaporates rapidly, and the rest is refractory aggregate The main paint layer. Then pour high-temperature molten iron on the paint layer on the inner surface of the high-speed rotating mold, and after the molten iron cools down, a cast iron pipe is formed. The main disadvantages of existing coatings are as follows: [0003] (1) The coating does not have leveling properties, and the coating is prone to defects such as coating bumps and spirals after spraying. Thereby the appearance of the gray cast iron pipe produced is particularly rough, which is difficult to meet...

AI Technical Summary

Problems solved by technology

Thereby the appearance of the gray cast iron pipe produced is particularly rough, which is difficult to meet the needs of foreign markets; (2), the suspension of the coating is relatively poor, and it must be continuously stirred to ensure the uniformity and consistency of the coating in production; (3), the coating It has high residual strength, that is, the residual strength of the coating is relatively high, so that the residual coating of the casting mold is not easy to clean, which affects production, and special equipment is needed to clean the residual coating; (4), the coating has strong water absorption, when coated After the first layer is sprayed, if it is not poured for a long time, and the temperature of the mold drops, the coating will absorb a large amount of moisture in the environment, and it will need to be re-sprayed the next time it is poured.