Method for eliminating looseness defect of wear-resistant pump shell casting

Abstract

The invention provides a method for eliminating the looseness defect of a wear-resistant pump shell casting. The method comprises the following steps: S1, mold modeling: arranging an exhaust passage on a sand core and / or a sand mold, enabling the head of the exhaust passage to be close to a neck triangular area of the pump shell casting, and enabling the tail of the exhaust passage to extend out of the sand core or the sand mold; and S2, conducting casting: injecting molten iron into a cavity, wherein gas generated by a core in a neck triangular area of the pump shell casting is exhausted from an exhaust channel, and the looseness defect generated during solidification as the gas in the neck triangular area is too much and exhausted gas is not timely enters the molten iron is avoided. According to the method for eliminating the looseness defect of the wear-resistant pump shell casting, the exhaust channel is formed in the neck triangular area, so that gas of molten iron on the mold and the core is exhausted from the exhaust channel, and the looseness defect generated during solidification as the gas enters the molten iron is avoided; and meanwhile, the sand core mold is baked and heated, so that the gas forming amount of the sand core is reduced, the looseness defect is further eliminated, and the casting quality is improved.

Description

technical field [0001] The invention relates to a casting method, in particular to a method for eliminating loose defects of an anti-wear pump shell casting. Background technique [0002] The traditional understanding in the industry is that the triangular area of ​​the neck of the pump casing belongs to the geometric and physical thermal joints of the casting. It is believed that the porosity that is prone to appear in the triangular area of ​​the casting is caused by solidification and shrinkage, which belongs to shrinkage cavity shrinkage defects. Therefore, an external chiller is used in the triangular area to eliminate the thermal influence and improve the feeding efficiency of the riser, or a large-capacity feeding riser is installed on its top surface, and some people think that the pouring temperature is too high to reduce the pouring temperature. However, the result of these measures is that the loose defects in the triangular area cannot be completely eradicated, a...

AI Technical Summary

Problems solved by technology

However, the result of these measures is that the loose defects in the triangular area cannot be completely eradicated, and sometimes even "shrinkage cracks" appear on the top surface of the triangular area of ​​the casting.

The loose defect in the triangular area of ​​the pump casing neck has always existed, but it is only a difference in size or degree. This defect directly affects the normal use of the equipment and reduces the service life of the pump casing.

Sometimes there will be a phenomenon similar to shrinkage and cracking, which will directly cause internal scrapping

The traditional method not only reduces production efficiency due to low yield, sometimes it is difficult to guarantee the delivery date, and increases production costs

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