Thin-wall complex cylinder body type iron casting shell mold pouring system and casting process

Abstract

The invention relates to a thin-wall complex cylinder body type iron casting shell mold pouring system. The system involves a pouring outer mold, a sand core and a runner; a pouring cavity is formed in the pouring outer mold; the sand core is arranged in the pouring outer mold, and the sand core is used for forming a cylinder body casting; the runner comprises an ingate, and the ingate is connected to the interior of the sand core; and a cast iron liquid enters the pouring cavity from the ingate in a top pouring type balanced mode, and an oil pan face of the cylinder body casting is formed upwards in a vertical mode. A casting process comprises the steps of top cover core positioning, sand core combining, sand core fixing and bonding, pouring preparation, cylinder body pouring and aftertreatment, a low-temperature pouring scheme is implemented on the casting, and the effective pouring time and the additional pouring time are controlled. According to the system and the process, a molding mode of the pouring system is improved, so that a reasonable pouring temperature is designed, the effective pouring time is controlled, the uniformity of casting materials is good, the compactness of mass structures of a cylinder barrel section is high, the surface quality is good, the percent of pass of castings is high, and the system and the process are suitable for casting cylinder body castings without large equipment investment.

Description

technical field [0001] The invention relates to the technical field of vehicle engine casting, in particular to the technical field of shell mold casting of thin-walled complex cylinder-type iron castings. Background technique [0002] As an important part of the engine, the cylinder block needs to have better performance to improve the internal power of the engine. The structure of the inner cavity is complex and the wall is thin. The existing large-scale production of thin-walled complex iron castings for small and medium-sized vehicle engine cylinders is traditional. The sand casting process usually adopts the "lying and horizontal pouring" molding method. Under this condition, the upper and lower box castings are placed in half or close to half (separated boxes), two-box molding, and bottom pouring. Or the pouring system with the main one-sided liquid inlet, the pouring process guided by the traditional pouring time concept, and the sand casting process plan for high-tem...

AI Technical Summary

Problems solved by technology

[0003] This traditional sand casting process scheme is difficult to ensure the quality compactness, uniformity requirements and technical requirements of the surface finish of the cylinder section of complex thin-walled cylinder body castings. Poor quality, casting porosity, many cold shut defects, casting leakage and reject rate usually reach 10-30%

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