There are ten casting processes in the casting classifi […]
There are ten casting processes in the casting classification, such as sand casting, investment casting, centrifugal casting, metal casting, squeeze casting, and lost foam casting. Today, the editor will give you a detailed introduction to these casting processes.
(1) Sand casting: A casting method in which castings are produced in sand. Steel, iron and most non-ferrous alloy castings can be obtained by sand casting methods.
1. It is suitable for making blanks with complex shapes, especially with complex cavities;
2. Wide adaptability and low cost;
3. For some materials with poor plasticity, such as cast iron, sand casting is a forming process for manufacturing parts or blanks.
(2)Investment casting: usually refers to making a pattern in fusible materials, covering the surface of the pattern with several layers of refractory materials to form a shell, and then melting the pattern out of the shell to obtain a mold without a parting surface. It is a casting scheme that can be filled with sand and poured after high temperature roasting. Often called "lost wax casting".
Process characteristics and advantages:
1. High dimensional accuracy and geometric accuracy;
2. High surface roughness;
3. It can cast complex castings, and the cast alloy is not limited.
Application: suitable for the production of small parts with complex shapes, high precision requirements, or other processing difficulties, such as turbine engine blades.
(3) Centrifugal casting: It is a casting method in which molten metal is poured into a rotating mold, and the mold is filled under the action of centrifugal force to solidify and shape.
Application: Centrifugal casting was first used to produce cast pipes. At home and abroad, centrifugal casting is used in metallurgy, mining, transportation, irrigation and drainage machinery, aviation, national defense, automobile and other industries to produce steel, iron and non-ferrous carbon alloy castings. Among them, the production of centrifugal cast iron pipes, internal combustion engine cylinder liners and shaft sleeves is the most common.
(4) Metal mold casting: refers to a molding method in which liquid metal is filled with a metal mold under the action of gravity and cooled and solidified in the mold to obtain a casting.
Application: Metal mold casting is not only suitable for mass production of complex-shaped aluminum alloy, magnesium alloy and other non-ferrous alloy castings, but also suitable for the production of iron and steel metal castings, ingots, etc.
(5) Lost foam casting (also called solid casting): It is to combine paraffin wax or foam models similar in size and shape to the castings to form clusters, brushed with refractory paint and dried, and then buried in dry quartz sand for vibration modeling , Pouring under negative pressure to vaporize the model, liquid metal occupies the position of the model, solidification and cooling to form a new casting method.
Process flow: pre-foaming→foaming→dipping coating→drying→modeling→pouring→falling out→cleaning
1. The casting has high precision and no sand core, which reduces the processing time;
2. No parting surface, flexible design and high degree of freedom;
3. Clean production, no pollution;
4. Reduce investment and production costs.
Application: It is suitable for the production of precision castings of various sizes with complex structures, unlimited alloy types and unlimited production batches. Such as gray cast iron engine box, high manganese steel elbow, etc.