Slow cooling sand box for lost foam casting

Abstract

The invention discloses a slow cooling sand box for lost foam casting, and the slow cooling sand box comprises a rectangular box body, wherein the upper part of the box body is opened and is covered by a box cover, four partition plates which are matched with the shape of a cavity in the box body are arranged in the box body, the head and the tail of each partition plate are spliced with one another, the bottom of the box body is provided with an installation clamping groove for the partition plates to be inserted in the direction of the inner wall of the box body, each partition plate is inserted into the corresponding installation clamping groove, a gap is formed between each partition plate and the inner wall of the box body, so that the partition plates and the inner wall of the box body form an air pumping chamber together, and the plate surface of each partition plate is provided with a plurality of through holes; one side surface of the outer wall surface of the box body is provided with an exhaust pipe, one end of the exhaust pipe communicates with an exhaust chamber in the box body, and the other end of the exhaust pipe is connected with a negative pressure system; and aninterlayer is arranged in the partition plate, a gauze layer and a heat-preservation cotton layer are inserted into the interlayer, the gauze layer is close to the center of the box body relative to the heat-preservation cotton layer, and the heat-preservation cotton layer comprises a plurality of layers of heat-preservation cotton. The slow cooling sand box for lost foam casting solves the problem that the cooling time of the sand box is too short, thereby ensuring the quality of castings.

Description

technical field [0001] The invention relates to the field of casting, in particular to a slow cooling sand box for lost foam casting. Background technique [0002] The lost foam casting technology is to bond and combine foamed plastic models similar in size and shape to the castings to form a model cluster. After brushing the refractory coating and drying it, it is buried in the foundry sand for vibration molding, and the liquid metal is poured under certain conditions. The method of vaporizing the model and occupying the position of the model, solidifying and cooling to form the required casting. [0003] Existing equipment using lost foam casting generally adopts air cooling or air cooling to cool down. Although this method ensures the sequential solidification of castings and the quality of castings to a certain extent, for some castings that require slow cooling It is not applicable; for example, most alloy steels, due to the action of alloying elements, undergo phase t...

AI Technical Summary

Problems solved by technology

[0003] Existing equipment using lost foam casting generally adopts air cooling or air cooling to cool down. Although this method ensures the sequential solidification of castings and the quality of castings to a certain extent, for some castings that require slow cooling It is not applicable; for example, most alloy steels, due to the action of alloying elements, undergo phase transformation during high-temperature cooling, and the structural stress changes, resulting in cracks on the surface and inside of the slab, and martensitic stainless steel, when cooled to 200~ At 300°C, due to the occurrence of martensite transformation, the volume expands, causing the structural stress to form the brittleness of the slab, and the slow cooling can greatly reduce the structural stress and thermal stress generated during the cooling process, and can prevent the generation of white spots , which is conducive to subsequent machining

[0004] However, in the existing slow cooling method, heating is generally used for heat preservation, which will generate huge energy waste, so the sand box structure used in the general lost foam casting process is not suitable for the slow cooling casting casting device ;Because the traditional sand box structure cooling casting is too fast, direct application will cause a large number of pores in the casting, and it is difficult to discharge the waste slag from the riser smoothly, affecting the quality of the casting, so how to find a slow cooling that can solve the cooling time is too short The sand box is particularly important

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