The application of the silica-sol investment casting process is becoming more and more widespread, and its superiority is a recognized fact, but at the same time it also has the need to improve and enhance the place, because the raw and auxiliary materials used in each factory machine operating conditions are different, so the process parameters are also very different, how to ensure that the finished rate of castings is a permanent issue.
Silica sol precision casting is a melt casting, the general silica sol precision casting process is as follows.
1. First according to the shape of the silica-sol casting parts manufacturing moulds.
2. Then use the silicone casting mould to create the same wax model as the part.
3. Put the wax model into a slurry made of silica-sol and quartz sand, and the wax model will have a layer of slurry on it, after which curing will occur. After several dips in the slurry and curing, the model is basically formed.
4. Dewaxing, the model is placed in hot water and the wax will melt and float on the surface, leaving the mould shell.
5. Casting and moulding.
The correct choice of various raw materials to ensure that the paint has the right specific gravity and viscosity is the key to paint control, for factories requiring a high powder-to-liquid ratio to join the powder-to-liquid regulator T3 can be freely controlled. In addition to silica sol and refractory powder, there are also wetting agent WET-10S, defoamer FA900 and paint guard GERM37, the role of paint guard is to prevent deterioration and ageing of the paint and loss of coating performance.
Generally, the passageway in valve bodies should be smooth, and considering the medium is corrosive, stainless steel valves made by silica sol casting process is the first choice.
How to shape the wax pattern is a crucial step in the production of valve body casting. Due to the bodies’ complex cavities or long liner dimension, one-time molding unworkable for the wax pattern. So we usually use two moulds and then welding the separate wax patterns together. The method not only ensure the valve body forming one-time, but also decrease its cost.
The final step in production is pressure test. Each piece will be inspected to guarantee gas-tight and no leakage before delivery.
Silica sol casting belongs to lost wax casting, mainly used for products with high corrosion resistance and precision dimensions, since it have much better surface quality and less geometrical deviation of dimensions. The main silica sol steel castings we ever made include meat grinder parts, valve castings, pump castings, marine hardware, and furniture decoration etc.Usually, Silica sol casting parts tolerance within GB/T6414, CT5~6, weight range from 20 grams to 50 kilograms, the surface finish is Ra6.3.
The above information is provided by the Silica sol casting supplier.
Room 1917, Hongyue Building,777# Chaoyang south street,Jingxiu Dist,Baoding,China.
P: 86 312 6780859