2 to 1 for stainless 1 to 1 for carbon steel 0 75 to 1 for aluminum.
Punching sheet metal thickness.
F 0 7 t l u t s displaystyle f 0 7tl uts where t is the sheet metal thickness l is the total length sheared perimeter of the shape and uts is the ultimate tensile strength of the material.
A deflecting punch requires more tonnage to break through the material and again increases distortion.
You will see from our cnc punch tooling tables that we have a range of die clearances to cover sheet metal materials from 0 4mm thick up to 5 0mm thick.
Punch force kn 80 x 3 x 0 3447 82 728 kn convert into tonnage.
The die clearance ideally increases as thicker sheet metal is punched but in practice some standard dies can be used for a range of materials.
Generally capabilities of of 0 9mm 20mm in thickness are able to be manufactured from sheet 3mm or plate 3mm but this tolerance depends mainly on the part.
Regardless if a shop follows some basic strategies it will be well on its way to better parts and greater throughput.
Also watch out for punch deflection especially if you re working with small hole diameter to material thickness ratios.
Shear strength 0 3447kn mm 2.
When considering sheet metal thickness a single sheet with punches holes is a good rule of thumb.
If punching one square hole in the 3mm thickness low carbon steel plate side length 20mm you will get.
One of the most mature technologies in metal fabrication punching is also one of the most misunderstood perhaps because the process can ccomplish so much punch myriad shapes form even bend flanges.