Compare a punching, blanking or piercing job's required force against a punch press's available capacity and evaluate the preliminary capacity margin.
| Parameter | Value | Calculation / Basis | Status |
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The checker first converts the entered job force and press rating into a common unit. It then applies the entered force allowance to the job force and adjusts the machine's rated capacity for the selected available capacity at stroke.
The preliminary utilization is then:
A utilization below 100% indicates that the entered available capacity exceeds the adjusted job force. The requested machine margin is checked separately.
Capacity margin represents the force remaining after the adjusted job force is compared with the available machine capacity.
The calculator also determines the minimum capacity required to satisfy the selected additional machine margin:
This allows you to distinguish between a machine that merely exceeds the job force and one that also satisfies the selected planning margin.
Punch presses are not always capable of delivering their maximum rated force throughout the entire stroke. Mechanical presses, for example, commonly have force ratings tied to a specified distance from bottom dead centre.
Utilization indicates how much of the available capacity is consumed by the adjusted job force.
These ranges are screening guidance rather than universal machine-selection standards.
For blanking and piercing, the job force can be obtained from a punching-force calculation using the total active cut perimeter, sheet thickness and material shear strength.
Where L is active cutting perimeter, t is sheet thickness and τ is material shear strength.
For multiple simultaneous holes or profiles, include the combined active perimeter when determining the job force.
What does this checker compare?
It compares an entered job force with the usable punch-press capacity at the specified point in the stroke.
What is the difference between rated and available capacity?
Rated capacity is the nominal press rating. Available capacity accounts for the percentage of that rating you expect to be available at the required stroke position.
What does utilization mean?
Utilization is the percentage of available press capacity consumed by the adjusted job force.
What happens if utilization is above 100%?
The entered job force exceeds the available capacity, so the machine fails the preliminary capacity check.
Why add a force allowance?
It provides a user-selected planning allowance around the entered job force. Actual allowances should be based on the specific process and engineering practice.
Does this work for hydraulic presses?
Yes, as a preliminary force comparison. However, hydraulic press force availability depends on the machine's pressure, cylinder characteristics and operating conditions.
Can I use this for forming operations?
Yes, if you have a reliable required forming force. The calculator simply compares the entered job force with machine capacity.
Does passing the capacity check guarantee safe operation?
No. Tooling, stroke, energy, die space, speed, machine stiffness and other process requirements must also be verified.