Casting molding sand for molding sand experimental instrument

Abstract

Casting molding sand for a molding sand experimental instrument comprises, by weight, 40-60 parts of quartz sand, 20-30 parts of electric smelting zircon sand, 5-10 parts of silica powder, 20-30 parts of land plaster, 10-20 parts of kaolin, 20-30 parts of sepiolite, 10-20 parts of pulverized coal, 3-8 parts of sodium silicate, 1-8 parts of hollow glass microspheres, 2-6 parts of lignin fibers and 10-20 parts of water. Raw materials with the small expansion factor are mixed with raw materials with the low caking property and good air permeability, so that the molding sand is low in shrinkage when serving as the casting molding sand and has excellent burnt-on sand prevention capacity, the wet viscosity between the molding sand in the early stage of machining and castings and the strippability between the molding sand in the later stage of machining and the castings are good, meanwhile machining air permeability, plasticity and fluidity are good, and thus the yield of the castings is increased, and the machining efficiency of the castings is improved.

Description

technical field [0001] The invention relates to the technical field of casting sand, in particular to a casting sand used for a sand experiment instrument. Background technique [0002] The role of molding sand in foundry production is extremely important. The casting waste caused by poor quality of molding sand accounts for about 30-50% of the total casting waste. Foundry production generally requires molding sand to have high strength and thermal stability to withstand various external forces and high temperatures; good fluidity, that is, the ability of molding sand to move between sand particles under the action of external force or its own gravity; Certain plasticity, that is, the ability of the molding sand to deform under the action of external force, and maintain the given shape when the external force is removed; good air permeability, that is, the ability of the pores of the molding sand to pass through gas; high sand production, also known as collapsibility , that...

AI Technical Summary

Problems solved by technology

[0003] Molding sand testing equipment has high requirements on the casting sand used. Existing molding sand testing equipment often has various casting defects in the casting production process, such as cracks, pores, sand holes, shrinkage cavities, etc., which affect the performance of the molding sand testing equipment. Use performance, and the occurrence of these defects is related to the bonding and detachment between the casting and the casting sand. The existing casting sand has poor service performance and is easy to bond with the casting, making the casting difficult to peel off, and the air permeability of the casting , Plasticity and fluidity are not good, which leads to rough surface of castings and high rejection rate of castings