How to choose tonnage of forging press
The calculation method is as follows:
1) P=p/q=(64 ～ 73) F/q, where P — tonnage of screw press (KN);
P – deformation force required for free forging (KN);
F – developed area of steel casting connected with burrs (cm2);
(64 ～ 73) – complex steel casting index is 73, simple casting index is 64;
Q is a deformation index, which can be divided into:
① When the steel casting must be free forged with large deformation stroke arrangement, deformation amount and deformation work, q=0.9~1.1;
② The steel casting must have a small deformation stroke arrangement and when the deformation work is carried out in free forging, q=1.3;
③ The steel casting must only be arranged with a small deformation stroke, but q=1.6 when a large deformation force is required for fine pressing.
2) P=(17.5 ～ 28) K · F total (KN), in which F total – total developed area of steel casting connected with burrs (cm2); K — steel grade index, refer to the section on the calculation of tonnage of machinery and equipment in Unit 3; (17.5~28) – The index 28 is used when the deformation is difficult (such as extrusion deformation, burr deformation, etc.) and the production efficiency is high, and the opposite is 17.5. The above formula is applicable to the calculation of tonnage of machinery and equipment required for 2~3 times of hammering forming. If one hammering forming is required, it shall be doubled according to calculation. There are three kinds of forging press: screw press, gear press and oil press.