Editing Swaging (section)

=== Lockbolts ===
A lockbolt is a fastener similar to a [[Bolt (fastener)|bolt]] in appearance and function. However, instead of using [[screw thread]]s which connect to a nut using a turning motion, a lockbolt has annular grooves around the shaft of the bolt (pin). After placing the lockbolt in a hole, a threadless collar is forced at high pressures around the annular grooves, deforming the collar and permanently locking it into place around the grooves. Swaging is the generic term for setting a lockbolt and collar assembly. During the installation cycle of a lockbolt, the collar is deformed around the pin with locking grooves using special tooling. The tool engages onto the pintail, which is an extra portion of pin material protruding past the collar that the tool grabs and pulls. This force on the pintail pushes the joint together, and the conically-shaped cavity of the tooling is forced down the collar, which reduces its diameter and progressively swages the collar material into the grooves of the harder pin.

As the force required for swaging increases during the process, the installation is finalised when the pintail breaks off.<ref>{{cite book | title = Handbook of Bolts and Bolted Joints | editor-first1 = John H. | editor-last1 = Bickford | editor-first2 = Sayed | editor-last2 = Nassar | publisher = Marcel Dekker | location = New York | year = 1998 | isbn = 978-0-8247-9977-9 | page = 311 }}</ref> Lockbolts could be viewed as a heavy-duty cousin of structural [[Rivet#Blind rivets|blind rivets]] ("pop rivets" in some regions), though the way the collar material's plastic deformation is achieved is different. Some tools are capable of "setting" both variants, as in both cases traction is applied to a sacrificial pintail.