A corrosion-resistant impeller casting process

Abstract

The invention discloses a corrosion-resistant impeller casting process, which is particularly characterized in that an aluminium material is selected as a pressing pattern mould material; an aluminium bar material is adopted as a mould material when the diameter is below 300 mm; primary aluminium is adopted as a mould material when the diameter is above 300 mm; silicon melt is adopted as mucilage; the compression environmental temperature is at 22-26 DEG C; the compression temperature is at 56-60 DEG C; the compression pressure is at 0.3-0.6 MPa; 100-120-mesh zircon sand is adopted as a sanding raw material; dewaxing is carried out by adopting high-pressure steam; a shell is roasted in the range of 950-1050 DEG C; an alloy is molten and poured by adopting stainless steel 316 and 304; and the pouring temperature is at 1580-1620 DEG C. By means of the process, the surface flatness of impellers is increased; material shrinkage and shell deformation are reduced; and the corrosion-resistant performance of the impellers is increased.

Description

technical field [0001] The invention relates to a manufacturing method of an impeller, in particular to an impeller casting process capable of improving corrosion resistance. Background technique [0002] As the core part of the pump product, the impeller plays an intuitive and important role in the performance of the pump and the reliability and life of the whole machine. From the development of pump products in our country to the present, the casting process of the impeller is produced by the sand casting process with wooden molds. In recent years, with the water glass casting technology and investment casting technology, the casting technology has developed more and more mature. However, the structure of the impeller is complex, especially the three-dimensional structure of the blade, which makes the casting process of the impeller develop slowly, especially the precision casting technology is difficult to use in the casting process of the impeller. Impellers cast by sa...

AI Technical Summary

Problems solved by technology

However, the structure of the impeller is complicated, especially the three-dimensional structure of the blade, which makes the casting process of the impeller develop slowly, and it is difficult to use the precision casting technology in the casting process of the impeller.

Impellers cast by sand casting have relatively large defects: heavy wall thickness, large roughness on the flow-through surface, and the general precision is 13-15, which is prone to defects such as sand inclusions, long nodules, and looseness.

In particular, there is a certain gap between the actual cast airfoil of the impeller and the hydraulic model, and the result is that the efficiency of the pump cannot meet the design requirements

At the same time, the processing volume of such a heavy impeller is also very large, the labor productivity is low, and the balance of the impeller is poor. These factors seriously affect the performance and life of the pump equipment.

If the impeller is subjected to blasting treatment, although the surface roughness of the impeller flow is improved, the processing cost of the impeller is greatly increased, the processing cycle is longer, and the production cost is also increased.