Clamping Thick Plastics

When plastic is at welding temperature it is essentially a liquid or it is molten. Therefore when the Powercore Welding Rod is at welding temperature, it is also molten. If too much external pressure is applied during the weld cycle the Powercore Welding Rod, and the molten weld zone can be squeezed out of the desired position. To properly weld with Powercore a small clamping pressure is all that is required. (less than 2 psi). More importantly the clamps should not allow the parts to move in any direction. This will allow the molten weld zone to stay in the same position, and the parts will stay aligned. The two illustrations below show the result of a constant force weld verses a static clamp weld for thick material.

1. A constant force is applied.
2. As the weld zone and Powercore heats up, the entire weld zone will expand and become molten.
3. Powercore is squeezed out of weld zone. Parts are out of alignment.

1. Clamping device holds parts in a static position
2. Weld zone will expand as it heats, causing internal pressure forcing parts into clamp.
3. As parts cool, a set screw is released to allow parts to shrink up slightly to prevent internal stress from forming.

For easy reference, we have provided all the above information in PDF format for you to download.