How to calculate the tonnage of pneumatic punch press

It is very important to choose a suitable pneumatic punch press to match the stamping parts and the punching tools. But how to calculate the needed press tonnage? This article is to introduce an easy calculation formula.

F=LTσbf

L refers to the length of the trimming line. For example, if a square hole is punched, the length of the trimming line is the sum of the lengths of the four sides of the square hole, which is exactly its perimeter.

T refers to the thickness of the material as above, the unit is mm.

f is the blanking coefficient, which is usually 1.3.

σb refers to the tensile strength of the stamped steel plate material. This must be checked in the manual, and there are some on the Internet.

The effect obtained by multiplying the above is the punching force, but the unit is N, and the conversion into tons needs to be divided by 9800, and the basic tonnage is obtained. Then consider the safety margin of punching and the ejection of the unloading pusher for the force required for other things, the high-speed pneumatic punch divides this tonnage by the factor of 0.7 to get the tonnage of the machine tool.