What is the part of the lockbolt shank that the puller clamps onto during installation?

The puller clamps onto the pintail during the installation of a lockbolt. The pintail is an extension of the lockbolt shank that serves a crucial purpose in the installation process. When the installation tool pulls the pintail, it creates a reaction that causes the lockbolt to expand within the material being joined. As the pintail is pulled, it ultimately fractures at a predetermined point, ensuring that the lockbolt is securely locked in place without damaging the surrounding materials. This mechanism is essential for achieving a proper and reliable joint.

In contrast, the other components serve different functions. The pin is the main part of the lockbolt that goes through the holes of the parts being joined, while the grip refers to the part of the shank that establishes the width of the joint. The head is the larger portion that provides a surface for the installation tool to work against, but it is not the part that the puller clamps onto. Understanding the role and function of the pintail is key for effective lockbolt installation.