Production process of casting of rapid start-and-stop power station extraction check valve

Abstract

The invention discloses a production process of a casting of a rapid start-and-stop power station extraction check valve. The production process comprises the following steps: 1, preparing a mold; 2,baking and feeding; 3, closing a box and matching a mold; 4, smelting alloy; 5, performing molten steel casting; 6, opening the box and performing treatment; 7, performing heat treatment on the casting; and 8, finishing and putting into storage, wherein in the step 1, according to the structural characteristics, the technical requirements, the product batches and the production conditions of checkvalve parts, a sand core is manufactured by using casting sand and a molding sand adhesive and a model of the casting is prepared. The production process is simple and reasonable in process; the sandmold and sand core can be strictly adjusted in the production process, so that the defects of sand holes, gas holes and dispersed shrinkage can be effectively avoided; and the casting is finely trimmed and polished for many times, so that wrinkles on the surface of the casting can be flattened effectively, the surface of the casting is smooth and flat, the size precision of the casting is improved and the rejection rate is reduced.

Description

technical field [0001] The invention relates to the technical field of valve casting, in particular to a production process for castings of air extraction check valves of fast opening and closing power stations. Background technique [0002] The fast opening and closing power station suction check valve is used in the gas extraction system of power plants or thermal power plants, or on non-corrosive medium pipelines such as steam and water in other systems, which can protect the safe operation of steam turbines. [0003] In the production process, the air extraction check valve is usually produced by casting. The production process in the prior art is complex and difficult to operate. During the production process, the problem of sand sticking is prone to occur. During the process, the pouring quality is affected, making the valve castings prone to defects such as trachoma, pores and shrinkage porosity, resulting in a high scrap rate of the castings, which seriously affects ...

AI Technical Summary

Problems solved by technology

[0003] In the production process, the air extraction check valve is usually produced by casting. The production process in the prior art is complex and difficult to operate. During the production process, the problem of sand sticking is prone to occur. During the process, the pouring quality is affected, making the valve castings prone to defects such as trachoma, pores and shrinkage porosity, resulting in a high scrap rate of the castings, which seriously affects the service life of the valve. There are grinding marks on the surface of the casting, which seriously affects the surface flatness and the process size of the valve casting. Therefore, it is necessary to design the production process of the fast opening and closing power station suction check valve casting.

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