Method for reducing machining allowance of inner cavity of centrifugal casting pipe

Abstract

The invention discloses a method for reducing the machining allowance of an inner cavity of a centrifugal casting pipe, and is aimed at providing a method which has the advantages of satisfying the process requirements for producing the high-quality centrifugal casting pipe having a smooth inner cavity with no defects and few defects. According to the key points of the technical scheme, the methodcomprises the following steps of: step 01. placing a soldering flux needing to be smelted in a cavity for drying; step 02. smelting molten steel according to the normal operation; step 03. when the molten steel meets the pouring requirements, tapping the molten steel, and pouring into a casting ladle; step 04. placing the soldering flux in the casting ladle, so that the soldering flux covers thesurface of the molten steel; step 05. carrying out centrifugal casting, mixing the molten steel in the casting ladle, the soldering flux not melted and the molten soldering flux being in contact withthe molten steel, and pouring into a high-speed rotating mold bucket; step 06. after completing the casting, taking off the casting pipe from a mold; and step 07. cooling the casting pipe to a room temperature. After the casting pipe is taken off from the mold, the casting pipe is cooled to the room temperature for several hours, a welding slag layer adsorbed on the inner wall of the casting pipeis automatically peeled off, and the inner surface of the casting pipe has metallic luster; and after the casting pipe is machined by 2-3mm, the roughness of the casting pipe reaches Ra12.5, the surface of the casting pipe has no casting defects.

Description

technical field [0001] The invention belongs to the field of centrifugal casting pipe casting methods, in particular to a method for reducing the machining allowance of the inner cavity of the centrifugal casting pipe. Background technique [0002] At present, the Chinese patent whose publication number is CN101704084 discloses a centrifugal casting pipe mold and a manufacturing process thereof. The centrifugal casting pipe mold is made of metal material, and the inner layer alloy of the pipe wall is a composite layer of heat-resistant mold steel. The supporting process methods include: adopting the centrifugal casting process to complete the forming of the outer wall of the centrifugal casting pipe mold with the help of a metal cavity; the metal of the outer wall of the centrifugal casting pipe mold is cooled to 20-100°C below the liquidus temperature At the same time, the heat-resistant mold steel molten liquid forming a composite layer is poured on the inner surface, and...

AI Technical Summary

Problems solved by technology

Although the machining allowance is placed, it is still unsatisfactory, and there are still casting defects inside the finished product.