Hydraulic pilot valve body casting and mold thereof

Abstract

The invention discloses a hydraulic pilot valve body casting. The hydraulic pilot valve body casting comprises a valve body main body and a valve body base, wherein the valve body main body is cylindrical, the valve body base is square, seven vertical flow passages are arranged in the valve body main body, and seven flow passage openings corresponding to the seven vertical flow passages are formedin the top of the valve body main body. The invention further discloses a hydraulic pilot valve body casting mold, wherein a sand core is formed by assembling a main sand core and a plurality of small sand cores, the main sand core comprises a left sand core and a right sand core, a hollow part for gathering gas is formed in the in the inner portion formed by bonding of the left sand core and theright sand core, and vertical exhaust holes are formed in the top of the small sand cores. A pouring cup and a dead head are arranged at the upper end of a shell mold, the bottom of the dead head isconnected with the upper end of a cavity, and a gate is connected with the lower end of the cavity through a pouring gate for injecting pouring liquid from the bottom of the cavity. The hydraulic pilot valve body casting has fewer surface air holes and smaller core breaking ratio in the casting process.

Description

technical field [0001] The invention relates to the field of valve body castings and molds thereof, in particular to a hydraulic pilot valve body casting and molds thereof. Background technique [0002] Hydraulic pilot valve body castings are mainly used in the hydraulic control system of large loaders. As a key component of the hydraulic system of construction machinery, it has the advantages of high integration, strong reliability, and long life, and has a good market prospect. However, my country's industry is large but not strong, and the current situation of overcapacity of low-end and mid-range products and almost complete reliance on imports of high-end hydraulic components needs to be resolved urgently. [0003] The existing hydraulic pilot valve body castings have the following disadvantages: 1. There are many air holes on the casting, and the reject rate caused by the plane air holes reaches more than 70%. The diameter of the sand core is only 5 mm, so it is diffi...

AI Technical Summary

Problems solved by technology

[0003] The existing hydraulic pilot valve body castings have the following disadvantages: 1. There are many air holes on the casting, and the reject rate caused by the plane air holes reaches more than 70%. The diameter of the sand core is only 5 mm, so it is difficult to quickly discharge the gas from the middle sand core to the outside of the mold, and a large part of the gas will invade into the mold to form pores in the casting; The sand core in the part is relatively large, with a thickness of about 20 mm, while the sand core connected to the central part of the sand is very small, with a diameter of only about 5 mm. High proportion of broken cores

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