Hot die forging is a kind of forging technology, which generally refers to the precision forging method that the metal blank is plastically formed into the shape and size of the forgings by means of the mold after the metal blank is heated to a temperature higher than the recrystallization temperature of the material.

In the process of forging, the hot  forging press and hammer are the two most widely used forging equipment.How to choose in the production process?

1. The motor releases energy through the flywheel. The pressure of the slider is basically static pressure, and there is no vibration and noise during operation. Due to the static pressure, the metal flows slowly in the mold, which is very advantageous for the formation of low-plastic alloys sensitive to deformation speed. Therefore, some metals such as heat-resistant alloys and magnesium alloys which are not suitable for die-forging on the hammer can be forging on a hot forging press.

2. The rigidity of the frame and crank linkage mechanism is large, the elastic deformation will change smaller during operation to ensure the dimensional accuracy. The slider has an additional guiding with trunk structure, which improves the guiding precision and the ability to withstand the eccentric load to ensures the horizontal accuracy .

3. The stroke of the slider is fixed, and each die forging step needs only one stroke to complete. The metal deformation is completed in one stroke of the slider, and the inner and outer layers of the blank are deformed almost at the same time, so the deformation is deep and uniform, the mechanical properties of the forgings are nearly same, and the streamline distribution is relatively uniform, which is beneficial to improve the internal quality of the forging. At the same time, because the stroke is fixed, therefore, it is not suitable for the blanking process such as lengthening and rolling, only the blanking operation with little change in the section can be completed.

4. With upper and lower ejector device, it is easy to demould the workpiece after forging. So the forging draft angle is small, and even the forgings without the draft angle can be produced.

In addition, the hot forging press can perform multi-die forging, automatic production, high forging precision .It is the most technical die forging equipment.

Compared with the die forging on the hot forging press, the former can reduce the metal loss by 5%~10%. Due to the high level of automation, it is suitable for mass production. The journal allowance of the modern light-duty vehicle crankshaft does not exceed 3mm as well as diameter tolerances and length tolerances, which can only be forged on presses to meet these tolerances. In the advanced die forging plants in mainland and abroad, hot forging presses are generally used instead of die forging hammers.