Mushan Precision Casting Co., Ltd. stainless steel precision casting is a method of lost wax precision casting process , which belongs to silica sol molten mold casting. It is different from sand mold casting and water glass casting as follows .

Difference 1: Different concepts

What is sand casting, water glass casting, silica sol casting?

1. The sand casting process uses wet clay sand as the main molding material, which is cheap.

2. The water glass investment casting process uses water glass quartz sand as the molding material, which can withstand temperatures up to 1800 degrees, but is more expensive than wet clay sand.

3. The silica sol investment casting process uses silica sol zircon sand as the molding material, which can withstand temperatures up to 2000 degrees. This molding material is very expensive.

Difference 2: surface quality and defects of castings

1. The surface of sand castings is very rough, and there are more surface and internal defects.

The following are some photos showing the surface quality of steel castings made by the sand casting process.

2. Water glass investment castings have better surface smoothness and fewer surface and internal casting defects.

Below are some photos showing the surface quality of steel castings made by this process.

3. Silica sol investment castings have very good surface quality, very smooth, and almost no surface and internal defects.

　Difference 3: Specification of unit weight and wall thickness difference

The sand casting process can produce very heavy and very large steel castings, but it cannot be used to produce castings that are too small, too complex, or very thin.

Precision casting can make the size of castings less than 10b , while sand casting is not always able to manufacture small and complex parts, such as precision casting.

Investment casting also has restrictions on the size and weight of sand casting.

The following table can be used to illustrate the difference between them.

The unit weight and size of the casting process limit the complexity of the wall thickness

Sand casting 5 – 3000kg 0.1 – 3 meters is not complicated > 5mm

Water glass investment casting 0.1 – 100kg 0.01 – 0.5 meters complex > 3mm

Silica sol investment casting 0.1 – 100kg 0.01 – 0.5 m Very complicated > 1mm

　　Difference 4: casting price

The cost of mold materials has caused large differences in the price of its castings. Wet clay sand is very cheap, water glass quartz sand is very expensive, and silica sol zircon sand is very expensive. Due to the complexity and preparation required, the cost of the precision casting process is always higher than that of sand casting.

For example, sand casting is 1.5 USD / kg, water glass investment casting is 2.50 USD / kg, and silica sol investment casting is 6.5 USD / kg.

Difference 5: Surface treatment.

Surface finishing is another big difference between investment casting and sand casting and water glass investment casting.

Investment casting can produce a finished product that shows a smooth surface and low tolerances under the effect of the pattern.

After removing the sprue gate and performing shot blasting, the cast billet is the final part delivered.

The surface of the water glass casting is more than that of the sand casting

For sand casting, the mold must be separated to release the final product. As a result, the parting line will leave the outside of the finished part. And because of the rough sand, the surface of the finished casting will be similarly rough. Therefore, additional cost and time are required in secondary processing to remove parting lines and smoother surfaces.

Different 6: Easy to design:

In investment casting, the ceramic shell mold is made of liquid slurry, so the parts made by the investment casting process can be made into almost any shape, so that engineers have great freedom in designing and can add Complex features and complex shapes.

For sand casting parts, in order to make it easily sand-out with less friction, it usually must be made into a cone (with draft angle) or shaped. For sand castings, manufacturing parts with internal voids or cavities is also a challenge. Sand casting requires a properly shaped core and inserting it into the mold to form the inside of the part. Sometimes multiple cores may be required, and it takes time to form and fix them in each mold.