Force required for cutting sheet metal

Thread starter eng_taha_a
Start date May 9, 2018
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Cutting Force Metal Sheet metal

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The discussion focuses on calculating the force required to cut sheet metal using an electrically powered shear. Key points include the importance of blade angle and clearance on cutting force, with the cutting force increasing as the blade progresses through the material. The formula for peak punch force is discussed, incorporating ultimate tensile strength (UTS) and the area being sheared, which is affected by the blade's position during cutting. Participants emphasize the need for accurate dimensions to perform calculations and suggest using a conservative estimate for the cutting force based on professional judgment. The final consensus indicates that the required force is significantly less than initially estimated, with a suggested range of 2,700 N to 6,000 N based on various calculations.

May 17, 2018

CWatters

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eng_taha_a said:

this dimension is about 100 mm

So at the end of a 1000mm cut I make the blade angle about 5.8 degrees, the length of the cut about 15mm and the triangular area under the blade about 11sq mm.

The eqns linked to by Asymptotic in #2 and jrmichler in #5 are similar and suggest the cutting force is some factor between 0.7 and 1.5 multiplied by UST multiplied by the area, so somewhere between..

0.7*350*11 = 2700N
and
1.5*350*11 = 5800N

Lets call it 6,000N.

eng_taha_a said:

will it be 420,875 N or less or more ?

The force required is considerably less.

The torque required is the force multiplied by the length of the blade so 6000 * 1m = 6000 Newton Meters.

eng_taha_a said:

this is the electric motor vision and ,but not the final decision

I notice that the arm that connects the electric actuator to the blade is shorter than the blade. Let's call the length of the actuator arm "L" (meters). Then the force the actuator would have to produce is: 6000/L Newtons.