March 12, 2012
PennEngineering® has introduced PEMSERTER® tooling that can install PEM® Type S self-clinching nuts permanently in thin aluminum sheets without the need to prepunch a mounting hole in a separate operation. The tooling and fastener pierce the mounting hole during the fastener-installation process, either with manual tooling or automatically with in-die equipment.
This method is suitable for use with Type S nuts with thread sizes ¼-20, 5/16-18, M6, and M8 and with a -2 shank length. Aluminum sheets must be between 0.059 and 0.79 in. thick and no harder than HRB 40. When in-die equipment is not used, a fixture, template, or other location device is recommended to ensure that the fastener is located consistently in the proper position on the sheet.
The tooling includes a modified punch and anvil to achieve the insertion. A raised ring on the anvil allows the fastener to pierce its own mounting hole and then assists in the final clinching process. The feature also creates an embossment in the panel, allowing sub-flush fastener installation on the shank side of the sheet and contributing ultimately to a clean installation.