Titanium LGP® Pull-Type Lockbolts : Technical Information : Installation Sequence -- Pull-in Method

Installation Sequence -- Pull-in Method

Pull-Type Lockbolts
Typical of LGPL18SC, LGPL2SP, LGPL4SC & LGPL4SP Fasteners
The pull-in system is an alternative to the hammer drive method of installing fasteners in interference fit holes. Pull-in refers to an innovative, two-stage fastener installation operation. Using a special Pull-in nose assembly, Huckbolt pins are first pulled into an interference fit hole without breaking off the pintail. The collar is then placed on the pin and using a standard Huck installation tool, the collar is swaged to complete the installation. Pull-in installation can reduce the factory noise to 50 decibels for installations with hydraulic tools or 75 decibels for pneumatic tools this is compared to over 110 dBA for rivet gun installations.
The pin is inserted from one side of the work surface The pull-in nose assembly is placed over the pintail. Note: a minimum of .375" (4 pull grooves must protrude to engage adequate pintail-chuck jaw engagement.)

Step 2
The tool trigger is depressed and the pin is pulled into the work piece. Note installation tools must be preset to proper pull pressure so that pintail will not separate during pull-in action. See table below.

Step 3
The pull-in tool is removed and a collar is placed over the pintail.

Step 4
The Huck installation tool with nose assembly is placed onto the fastener. The tool is actuated causing the nose assembly to pull on the pin and push on the collar. This action seats the head of the fastener and begins swaging the collar material into the pin’s locking grooves, providing a permanent lock between the pin and collar.

Step 5
Continued swaging of the collar forces the collar to stretch in length, resulting in a corresponding stretch of the pin. This precise lengthening of the pin and collar is what causes the high consistent clamp-up of the LGP Lockbolt system.

Step 6
When collar swaging is complete, the tool continues to pull until the pin separates in tension (at a pre-determined force) at the break neck groove. The tool trigger is then released and the nose assembly with tool is pushed off the installed fastener, completing the installation cycle. The entire sequence occurs in less than two seconds.

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