Enter the mean circumference of the shell (often based on the mean diameter), the stock thickness, and the material tensile strength (or an estimated drawing/flow stress) into the calculator to determine the drawing force.

Drawing Force Calculator

Enter any 3 values to calculate the missing variable

Drawing Force Formula

The following equation is used to calculate the Drawing Force (a simplified estimate based on wall area and an assumed tensile/drawing stress).

FD = C*T*S
  • Where FD is the drawing force (lbf)
  • C is the mean circumference of the shell (in)
  • T is the stock thickness (in)
  • S is the tensile strength (psi, i.e., lbf/in^2)

To calculate the drawing force, multiply the circumference by the stock thickness (this gives the wall cross-sectional area), then multiply by the tensile/drawing stress.

What is a Drawing Force?

Definition:

Drawing force is the tensile force required to pull (draw) a thin-walled shell/cup through a forming die in sheet-metal drawing or ironing. This calculator uses a simplified estimate based on shell wall area and an assumed material stress.

Drawing is a metalworking process in which material is pulled through or into a die under tension to form a new shape; real drawing forces also depend on factors such as friction and die/punch geometry.

How to Calculate Drawing Force?

Example Problem:

The following example outlines the steps and information needed to calculate the Drawing Force.

First, determine the mean circumference of the shell. In this example, the mean circumference is measured to be 5 inches.

Next, determine the thickness of the material. This material is 1.5 inches thick.

Next, determine the tensile strength of the material. For this problem, the tensile strength is found to be 5,000 lbf/in^2.

Finally, calculate the drawing force using the formula above:

FD = C*T*S

FD =5 * 1.5 * 5000

FD = 37,500 lbf