What matters should be paid attention to in sand mold compaction?

Be careful not to put your hands on the sand box when tamping the sand mold.

A casting method uses molding sand and core sand as molding materials to make molds, and liquid metal fills the molds under the action of gravity to produce castings. Steel, iron and most nonferrous alloy castings can be obtained by sand casting. Because the molding materials used in sand casting are cheap and easy to obtain, and the mold is simple to manufacture, it can adapt to the single piece production, batch production and batch production of castings. For a long time, it has been a basic working procedure in foundry production.

The mold used in sand casting usually consists of an external sand mold and a core. In order to improve the surface quality of castings, a layer of paint is often painted on the surface of sand molds and cores. The main components of the coating are powdery materials and binders with high fire resistance and good high-temperature chemical stability, and convenient carriers (water or other solvents) and various additives are added.

The basic raw materials for making sand molds are casting sand and sand binder. The most commonly used casting sand is siliceous sand. When the high temperature performance of silica sand can't meet the use requirements, special sand such as zircon sand, chromite sand and corundum sand is used.

In order to make the sand mold and core have certain strength and not be deformed or damaged when transporting, molding and pouring liquid metal, it is generally necessary to add molding sand binder during casting to bond loose sand particles to form molding sand. Clay is the most widely used binder for molding sand, and various drying oil or semi-drying oil, water-soluble silicates or phosphates and various synthetic resins can also be used as binders for molding sand.