Sand Casting Process

Advantages of Metal Casting Products
1. Sand casting process is relatively cheap and sufficiently refractory even for steel foundry use.
2. The sand is mixed with a suitable bonding agent (usually clay). The mixture is moistened, typically with water, to develop strength and plasticity of the clay and to make the aggregate suitable for molding.
3. Sand casting process is suitable for shaped or non-symmetrical parts, as well as large parts up to 15,000 lbs./6,800 kg or more.
4. The sand is typically contained in a system of frames or mold boxes know as a flask.

Application of Sand Casting Process
1. Ferrous metal casting has wide adaptability, which can be used for small, large, simple and complex parts.
2. It is also applicable to the production of engine bearer, engine manifolds, cylinder cover and gear box in automobiles, lathes, shipbuilding and locomotive industries.

Description
Sand casting process is a traditional metal casting process characterized by using sand as the mold material. Sand casting products are produced in specialized factories called foundries. Over 70% of the metal casting products are manufactured by sand casting.
The basic casting concept is also called green sand molding or green sand casting. All the other casting techniques employed in the rest of the casting and molding processes are in many ways, just like sand casting or green sand molding.

Process Cycle
The sand casting process cycle consists of six main stages, as follows:
1. Mold-making
The first step in the metal casting process is to create the mold. In an expendable mold process, this step must be performed for each casting. A sand mold is formed by packing sand into each half of the mold. The sand is packed around the pattern, which is a replica of the external shape of the casting.
2. Clamping
After the mold is made, the molten metal should be poured. The surface of the mold cavity is first lubricated to facilitate the removal of the casting. Then the cores are positioned and the mold halves are closed and securely clamped together.
3. Pouring
The molten metal is kept at a set temperature in a furnace. After the mold has been clamped, the molten metal can be ladled from its holding container in the furnace and poured into the mold.
4. Cooling for sand casting process
After the molten metal enters the cavity, it begins to cool and solidify
5. Removal
After the predetermined solidification time has passed, the sand mold can simply be broken, and the casting removed.
6. Trimming
During cooling, the material from the channels in the mold solidifies attached to the part. This excess material must be trimmed from the metal casting products either manually via cutting or sawing, or using a trimming press.

Materials for Sand Casting
This metal casting process can make use of almost any alloy. An advantage of sand casting is the ability to cast materials with high melting temperatures, including steel, nickel, and titanium. The most common used materials in sand casting process are aluminum alloys, brass alloys, cast iron and cast steel.

Tooling for Sand Casting
The main tool for sand casting process is the pattern that is used to create the mold cavity. The pattern is a full size model of the part that makes an impression in the sand mold. However, some internal surfaces may not be included in the pattern, as they will be created by separate cores. The pattern is actually made to be slightly larger than the part because the casting will shrink inside the mold cavity. Additionally, several identical patterns may be used to create multiple impressions in the sand mold, thus creating multiple cavities that will produce as many parts in one casting.

Images Information

Material: HT-250 Technology: Sand casting process Application: Major parts of engineering machinery Gross weight: 300kg

Material: HT-250 Technology: Sand casting process Application: Major parts of engineering machinery Gross weight: 85kg

Material: HT-250 Technology: Sand casting process Application: Major parts of engineering machinery Gross weight: 25kg

Lantyto® is a professional metal casting manufacturer and supplier in China. We have the capacities to carry out sand casting process, gravity casting, low pressure casting, centrifugal casting and shell casting. Additionally, we provide forging process products and precision machined products for our clients. We possess advanced equipments, such as imported Oxford spectrograph from Germany, tensile machine, sclerometer, heat treating equipment, special processes and large-scale parts processing equipment.