Heavy Steel Coatings

The near-net-shape technology has showed an emergence in United States in the end of 1980s, taking the outstanding product quality (especially the external appearance quality) as center. Because the near net shape castings increase in value obviously, numerous foundry factories have become interested in this technology.To near net shape metallic castings, the chief mission is to raise its surface quality. About 80% to 90% of castings are made by sand mold(high efficiecy and low cost), but sand burn-on phenomena is incapable of solving from A to Z. Be order to let near-net-shape come true, we must solve the sand burning problem. Those medium and small castings can be cleared easily, the other way round, those large and thick ones is troublesome.Various ways can be selected , but economic and viable means should be the foundry coating. Analyze and dicuss characteristics of three current mould sand(clay sand, sodium silicate sand and gummy sand) and the large and thick steel castings, this research draws up to take the fireproof type and sintering coating as project to resolve the burn-on problem of the large foundies.After analyzing mechanism of burning-on of the heavy steel castings and sintering coating , acquire the fire-resistant type water-base and alcohole-base dope formulation of clay bonded sand and soluble glass sand by way of orthogonal experiment, then on the bedrock of water glass sand alcohole formulation, take the specialty of gummy sand into account, adopt double- layer coating project of the bottom paint add to a layer of face dope, develop the resin sand coating formulation; because manufacyuring of the steel casting in our country has been utilizing soluble glass sand long time, on the foundation of water glass alcohole-base dope formulation again, appending certain powder to accelerate sintering process, obtain the successful alcohole-base sintering dope formulation.The clay bonded sand water-base coating, the soluble glass sand and resin-sand alcohole-base dope, sintering paint are experienced via factory, produce validation proves that its anti-burning-on function isiscompellent.Calculate its cost respectively, compare with the same kind commercial foundry coating, its price superiority is visible and distinct.Its economy and application effect express express that coating formulation aquired is a combo of low cost and high performance.