Hard metals like steel and larger drill bits require even slower speeds.
Psi required to punch through a sheet of aluminum.
Problem 115 what force is required to punch a 20 mm diameter hole in a plate that is 25 mm thick.
Multiply x 1 25 stainless steel.
In general it s a good idea to drill through metal using as slow a speed as possible using a drill bit for metal.
With a small twist bit 1 16 in.
Multiply x 36 brass 1 4 hard.
Multiply x 70 copper 1 2 hard.
You can calculate the punching tonnage been required with the help of the following punching force calculation formula blanking force formula.
Shear strength n mm 2.
For round holes in steel this is diameter pi 30.
To calculate the force to punch holes in metal you determine the cross section in shear and multiply it by the shear strength of the metal.
Sheet rb 40 000 276 80 25 astm a 36 bhn 119 159 58 80 000 1 20 20 25 45 50 carbon hr sheet bhn 200 80 000 552 1 60 25.
Tonnage required for punching round holes.
Recommended die clearance in of thickness low carbon hr steel rb 70 50 000 345 1 00 20 low carbon c r.
Multiply x 1 60 a36 steel recycled.
To 3 16 in you can drill through most metals at 3 000 rpm.
The shear strength is 350 mn m 2.
Multiply x 52 high carbon steel.
Punching force calculation formula.
When the sheet metal is put through the process of bending the metal around the bend is deformed and stretched.
Figures in the body of this chart are u s.
How to obtain tonnage required for punching round holes.
Tonnage in mild steel 3 1416 x diameter of hole x material thickness x 25 example.
As this happens you gain a small amount of total length in your part.
The formula is perimeter times thickness times shear.
3 1416 x 2 000 x 250 x 25 39 26 tons.
Tons 2000 lbs required to punch round holes in mild carbon steel having a shear strength of 60 000 psi subject to the multiplier from table above of 75 to 1 3 according to the state of the metal whether annealed or work hardened.
Required tonnage for punching mild steel with tensile strength of 50 000 psi how to calculate required tonnage for punching mild steel with tensile strength of 65 000 psi how to calculate the diagonal dimension of a punch.
If you punch round holes or square holes or some other forms of holes through a given thickness of metal you just want to know the force required to punch a hole in steel.
