What is the position of silica sol casting in precision foundries

What is the position of silica sol casting in precision foundries?

Precision casting is a casting process that we often hear at present. Precision casting manufacturer more familiar, precision casting is divided into three types:

　　1, Silica sol precision casting;

　　2 water glass casting;

　　3, composite casting;

the difference between these three casting methods is the use of wax. And shell making the material is different, take silica sol for example, silica sol is used at low temperature. Wax and warm wax to carry out make wax mold, and then use wrong sand, moying sand, wrong powder and silica sol and so on to make shells, according to the different needs of each product, can be made4-8 layer shell; The process of water glass is the use low temperature wax to make wax mold, and then bubble  alkali, quartz sand, etc. for shell making; The composite process is that the first two processes are interlaced together. The first two or three layers are made of silica sol process, and the last few layers are made of sodium silicate process.

If these three processes are compared in terms of size, silica sol is very suitable for small pieces, the surface will be relatively fine, and the precision roughness value can be reached. RA3.2-6.4 between, tolerance size control will be better, and with silica sol process, some places can not be processed, one-time molding, which can also save a lot of costs. In the case of composite type, neither the surface nor the tolerance size is as good as the silica sol process, but the composite process can make a bigger casting in the ruler. In terms of inches, it is better than that of water glass, and the outer surface is also good, sometimes it can be reached. Ra6.4-12.5 about, water glass and composite process compared with another grade.

So precision casting manufacturer in general, what is the application of silica sol in precision casting?

Silica sol is mainly used in the adhesive of precision casting coatings and can be used made shell reinforcement coating and surface coating. Precision casting manufacturer small particle silica sol will be used in precision casting on the other hand, it is used to replace ethyl silicate, which can not only reduce the cost of casting, but also improve the working environment and conditions. When silica sol for thin shells precision casting at that time, the strength of the shell will be higher, the finish of the casting will be better, the dimensional accuracy will also be higher, the shape will be better than the quality of water glass, and the price will be lower than that of ethyl silicate. For large castings, castings with high surface finish requirements and castings with no or little margin are also more suitable for casting with silica sol.  With. Precision casting the manufacturer put silica sol as a high temperature resistant coating for the mold, the coating can have very good wear resistance and heat resistance, can also reduce the loss of molten metal liquid at high temperature to the mold, and also help the casting mold release.