How to Calculate a Bolt's Clamping Force
- 1). Determine the preload force on the bolt. This force is caused by rotating the bolt, which stores force, much like a spring. This can be experimentally determined using a force transducer (if the value is not already known). As an example, assume the preload force is 2 lbs.
- 2). Determine the tension force on the bolt. This can also be measured using a force transducer (again, if the value is not already known). Assume the tension force is 3 lbs.
- 3). Subtract the preload force from the tension force. In our example, the tension force (2 lbs.) subtracted from the preload force (3 lbs.) gives 1 lbs. This is the bolt's clamping force.
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