Why do so many parts use forgings not castings?

 1. The forming principle of forgings and castings:

A forging is an object in which metal is subjected to pressure and plastic deformation to produce the desired shape or appropriate compression force. This force is typically achieved by using a hammer or pressure. The forging process creates a fine granular structure and improves the physical properties of the metal. In the practical use of components, a correct design can make the particle flow in the direction of the main pressure. Castings are metal molding objects obtained by various casting methods that molten liquid metals are injected into prepared castings by casting, injection or other methods, and after cooling, sand falling, cleaning and post-treatment, etc., objects with certain shapes, sizes and properties are obtained.

2. Reason forgings perform better than castings:

The organizational structure and mechanical properties of metal can be improved by forging. Casting organization after thermal forging method, has deformation due to metal deformation and recrystallization, making original bulky dendrite and columnar grain to fine grain and uniform axial recrystallization , making the ingot in the original segregation, porosity, slag compaction and welded become more close, mechanical properties of the metal The mechanical properties of castings are lower than those of forgings of the same material.In addition, the metal forging process can guarantee the continuity of fibrous tissue, the forging of fibrous tissue and appearance consistent, metal flow is complete, can guarantee the parts with good mechanical properties and long service life with precise die forging, cold extrusion, extrusion temperature and other process of forging, is incomparable by casting.

3.The main equipment used in the production of forgings:

The production equipment for forgings mainly consists of two types:——hammer and press:

According to the different driving medium, the forging hammer is divided into steam hammer, air hammer, belt hammer and hydraulic hammer. According to the forming way of forgings, it can be divided into die forging hammer and free forging hammer. According to the control mode, it can be divided into CNC hammer and manual control hammer. Because steam hammers and air compressor hammers are far less energy efficient than electro-hydraulic hammers/hydraulic hammers, many hammer manufacturers have stopped making such hammers.In recent years, some hammer manufacturers have upgraded the die forging electro-hydraulic hammer into striking capability and published PLC control, greatly reducing the dependence on the forging workers' operation experience and providing possibilities for the realization of forging automation.

According to the different power transmission, Press can be divided into crank press, screw press and hydraulic press. Crank press is an eccentric shaft/crankshaft through the connecting rod to drive the slider to move up and down, including small tonnage of open punch and closed hot die forging press;The screw press drives the up and down motion of the slide block through the rotation of the screw rod changing direction continuously, which can be divided into friction screw press and electric screw press.The screw press and the hot die forging press are generally used in the die forging industry.The working principle of hydraulic press is that the piston is pushed up and down by hydraulic oil, which can be used for die forging or free forging.