The methods of silica sol precision casting include sand casting, special casting, precision casting, V-method casting, and precision casting. Precision casting in precision casting belongs to special casting. Do we all know the process of silica sol casting castings when casting silica sol?
The process of silica sol precision casting parts is as follows:
1. Pressing wax molds
Press the processed wax paste into the mold cavity, condense the ice water in the ice water machine, take it out, and place it in the water tank for a period of time. After repair and inspection, a single wax mold was obtained, which can be understood as a pressure cast part.
2. Manufacturing molds
Mold is a type of mold used to press casting patterns, in order to ensure the quality of wax molds. The mold must have high dimensional accuracy and a small surface roughness value.
3. Mold repair
The quality, surface quality, and degree of deformation of wax molds determine some important parameters of the product. Therefore, the wax mold workshop needs constant temperature control to minimize the deformation of wax molds. At the same time, surface inspection is also required for each wax mold, and any flow marks should be washed away. At the same time, when repairing the mold, burrs, burrs, and closing lines of the wax parts should be removed, and minor defects should be repaired.
4. Combination wax model (group tree)
After repairing the mold, for qualified individual wax molds, in order to improve productivity, the individual wax molds are fused and welded onto a pre made wax common pouring system. Forming a wax model group, usually 2-80 wax models can be fused onto one wax model group.
5. Cleaning wax molds
After the wax model group is left to stand for more than 45 minutes, it can be cleaned before shell making and slurry hanging. The wax model group after the number of groups must be cleaned to remove surface wax and grease, and improve the adhesion of the shell.
6. Manufacturing shell
After immersing the wax mold with coating, it is placed in the shell making room for drying, and the surface layer is dried naturally. The transition layer and back layer are accelerated by rotary air drying, and this process is repeated 5-7 times (5-6 layers for small castings and 6-9 layers for large castings).
7. Shell roasting, casting, sand removal, and cleaning
The dewaxed shell needs to be baked during casting, and the shell should be placed in a 1100 ℃ oil or electric furnace for 50 minutes. Its main purpose is to remove residual wax after dewaxing and improve the strength and breathability of the mold shell, preventing deformation or cracking of the mold shell during pouring.
8. Dewaxing and wax treatment
Pour the mold shell into the steam dewaxing axe to melt the wax mold and let it flow out from below. After being separated by a water separator, the wax liquid is collected and placed in a water removal bucket for further wax water separation and removal of impurities in the wax.
