The most economical pierce nut is the universal one. Dies coin the metal and force it into nut undercuts. This nut is also available as a strip pierce nut in which strands of wire hold nuts together in a continuous strip. The nut strip simplifies automatic assembly by eliminating feed hoppers and nut orientation stations.
In the assembly operation, pierce nuts are fed continuously under a plunger. With each press stroke, the nut pilot is driven through the metal panel, piercing the mounting hole for the fastener. Clinching die ribs cold-flow the panel metal into the undercut, securing the nut to the panel. High-strength pierce nuts are used where greater stresses are encountered.
Pierce die nuts are designed for dynamically stressed applications. They have great resistance to pull-through, shear, and impact loads. Flush mounting makes the nut self-sealing.