A method for casting integral multi-way valve body castings

Abstract

The invention discloses a monolithic multi-way valve body casting piece casting method which comprises the following steps: preparing a core preparing mold, and checking and cleaning the mold; preparing a main core by mold sand, and after the shape of the main core is finalized, spraying a mold release agent, and demolding; preparing small cores, and drilling exhaust holes in the small cores; finishing to remove burrs on the main core and the small cores, and removing a transition jet nozzle on the main core; fixing the main core by a sand core bonding preparation tooling, firstly assembling the small core at one side, and then assembling the small core at the other side; mounting the assembled sand core into a shell body; and casting a valve body: performing a pouring process at two sides of a side thin gate at the same time, using an exothermic riser with the diameter of 120 mm and the height of 220 mm, and placing special cold iron at the bottom face of the shell body. The monolithic multi-way valve body casting piece casted by the casting method has the advantages that the linearity of a main valve hole casting blank is controlled to be less than or equal to 1.0 mm, and the valve hole linearity is ensured; the casting piece pore shrinkage, shrinkage porosity, internal gas holes and other casting defects, especially defects of micropores in the casting piece, are solved; and the compactness of the internal structure is improved.

Description

technical field [0001] The invention relates to the technical field of engineering machinery equipment manufacturing, in particular to a method for casting integral multi-way valve body castings. Background technique [0002] The product produced by the manufacturing method is a key part of the hydraulic control system of the large excavator, and is the development direction of the hydraulic control system of the large excavator today. [0003] An excavator, also known as an excavator, is an earth-moving machine that uses a bucket to excavate materials that are higher or lower than the bearing surface, and load them into transport vehicles or unload them to the stockyard. Judging from the development of construction machinery in recent years, the development of excavators is relatively fast, and excavators have become one of the most important construction machinery in engineering construction. [0004] Most of today's large excavators have hydraulic control systems. The hy...

AI Technical Summary

Problems solved by technology

[0005] The hydraulic valve is a key component of the hydraulic system. The hydraulic valve structure and precision requirements of large excavators are very high, especially for some valves with multiple oil circuits, the temperature rises rapidly during the working process, and the temperature is too high, causing the hydraulic valve to not work stably. , and the amount of wear is large, the pressure pulsation or impact vibration of the hydraulic system will cause the valve body to leak, and it is easier to leak under the high-pressure working state with a pressure ≥ 35Mpa. The hydraulic valve body casting shrinkage cavity, shrinkage porosity, internal pores, etc. The problem is often a defect of the product, requiring higher internal structure compactness and the straightness of the main valve hole casting blank is less than 1.0mm