Centrifugal casting radiant tube paint and preparation method thereof

Abstract

The invention is a centrifugal casting radiant tube coating and a preparation method thereof, the coating comprises the ingredients (mass percent) of: 25-30% of diatomite of, 5-10% of zircon powder, 1.0-1.2% of titanium powder, 1.5-1.8% of iron powder, 4.5-5.0% of sodium bentonite, 2.0-2.5% of polyvinyl alcohol, 0.8-1.0% of sodium alginate, 3.5-4.0% of silica sol, 0.8-1.0% of sodium dodecylbenzene sulfonate, 0.05-0.08% of silane and 46.82-49.95% of water, wherein, the mass percent of the diatomite and the zircon powder is not less than 35% and not more than 37%, the mass percent of the titanium powder and the iron powder is not less than 2.7% and not more than 2.9%, and the mass percent of the sodium bentonite plus the polyvinyl alcohol plus the sodium alginate is not less than 8.0% and not more than 8.2%. The inventive coating is used for the centrifugal casting radiant tube after dry-blending, mixed grinding and sieving, uniformly distributed bulges (namely pitting surface) can be formed on the outer surface of the radiant tube to improve heat efficiency of the radiant tube. The inventive coating also has excellent adhesive force, high temperature strength and crack resistance, thus reducing defects on the surface of the radiant tube and improving quality of complex tube. Using the inventive coating to cast the radiant tube can result in remarkable economical benefit.

Description

technical field [0001] The invention relates to various centrifugal casting alloy steel pipe coatings and a preparation method thereof, in particular to a centrifugal casting radiant tube coating and a preparation method thereof, belonging to the field of casting technology. Background technique [0002] In the heat treatment industry of mechanical processing, automobile manufacturing and steel industry, in order to ensure the internal quality of the workpiece and meet the requirements of certain surface heat treatment processes, many heat treatment furnaces use indirect heating with a protective atmosphere. Since the radiant tube heating effectively avoids oxidation and decarburization of the heated surface, it creates conditions for heat treatment under a protective atmosphere. At present, radiant tubes are widely used and developed rapidly. Radiant tubes generally have two types of electric heating and gas heating. The method of radiant tube heating has many advantages ...

AI Technical Summary

Problems solved by technology

However, it is not easy to obtain evenly distributed pockmarks on the outer surface of the tube when it is used for centrifugal casting of radiant tubes

Japanese patent JP54019420-A also discloses a coating for centrifugally cast steel (or nickel-base alloy) pipes, which contains B 4 C, it is easy to form a layer of boron-containing hardened layer on the surface of the cast tube, which is beneficial to improve the wear resistance of the cast tube surface, but it is not easy to obtain uniformly distributed pockmarks on the outer surface of the tube when used for centrifugal casting radiant tubes

Invention patent RO95387-A also discloses a refractory coating for centrifugal steel casting, containing 1.5-5% bentonite, 0.3-1.5% starch, 2-5% water glass, 0.1-0.2% phenol or formaldehyde solution, but the human body After inhaling phenol, it will cause dyspnea and headache, and it will irritate the eyes, and formaldehyde is also a protoplasmic poison, which can be combined with protein. Bronchial asthma occurs, because the paint is harmful to the body, it should not be used in the production of centrifugal casting radiant tubes