Bucket tooth shell mold casting method

Abstract

The invention discloses a casting method for a bucket tooth shell mold applied in the casting field. The method includes sand box molding and vibratory pouring. The sand box molding includes steps such as upper and lower box molding, box closing, and covering insulation layer; a shell mold and a sealing shell with a thickness not greater than 3mm are made in a horizontal metal mold, and the upper metal mold is removed. , replace it with a box body, check the shell shape, and repair the local unformed parts with coated sand to ensure that the sand box is vacuumed and air-tight. Add steel shots to the box, cover it with agricultural film, vacuumize it, and demould it from the lower metal mold to complete the shape of the upper and lower box; lower the core to close the box, and cover the top surface and surroundings of the sand box with quartz sand or insulation cotton insulation layer. The sand box is in a vacuum state during pouring, vibrates immediately after pouring, and stops vibrating before the vacuum is withdrawn. By adopting the casting method of the method, the amount of coated sand used is greatly reduced, the as-cast crystal grains of the wear-resistant parts are refined, the generation of cracks is avoided, and the energy consumption of heat treatment is reduced.

Description

technical field [0001] The invention is applied in the field of casting, relates to shell mold casting, and is suitable for the casting production of bucket teeth of wear-resistant parts of excavators. Background technique [0002] Bucket teeth are the wear-resistant castings with the largest consumption on construction machinery excavators. They require the unity of high toughness and high hardness. Most of them are made of alloy steel or bimetal. The casting process mostly uses lost foam and resin sand, and a few of them use shell casting. The surface quality of bucket tooth castings produced by the process is good. In general, bucket teeth need to be heat treated to obtain high hardness and wear resistance. The heat treatment of bucket tooth castings is divided into return pretreatment, quenching and tempering treatment, etc. [0003] Shell mold casting first makes the shell mold, and the coated sand formed by the mixture of silica sand or zircon sand and resin is formed...

AI Technical Summary

Problems solved by technology

In order to ensure the molding strength of the shell mold, its thickness is generally not less than 5mm. Expensive coated sand uses large materials and high production costs. Therefore, even though the surface quality of bucket tooth castings is better, there are few manufacturers using shell molds.

Images