1. The tension of the nail core itself is not stable, the breaking point force is very close to the tension of the nail core itself, or the heat treatment is not done well, and the nail core is brittle.
2. The nail core has been damaged before riveting.
3. The claw piece of the nail pulling gun is not adjusted well and is not on the same plane. The claw piece cuts the nail core.
4. The air pressure of the pull riveter is not enough, and the claw is worn. The first pull riveting has caused damage to the nail core, so that the tension at the damaged part is less than the breaking point force. When pulling again for the second time, the nail core will break from the injured part.
Post time: Jan-26-2022