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GP® High Strength Tension Pull-type Lockbolts

Titanium GP™ Pull-Type Lockbolts

GP™ High Strength Tension Pull-type Lockbolts
Huck's (GP™) Lockbolt fastener is a high-strength aerospace fastener. Easily one of the most cost-effective high strength aerospace fastener available. The GP™ can help reduce aircraft weight due to the use of aluminum collars instead of steel collars or nuts used on threaded fasteners to achieve full tension values.
The GP™ is designed for use in both interference and clearance fit conditions. Common applications include wing spars, stringers, webs, fuselage panels and major joins.
The GP™ is a high strength version of the Huck Lockbolt family used on aircraft for over 50 years. The GP™ is available in protruding, MS24694 & MS20426 full tension 100° flush head styles. Unlike threaded fasteners, Lockbolts install rapidly and cannot vibrate loose. Their unique design assures predictable, consistent clamp force.
Design Features

The GP™ Fastener features a tapered root diameter and variable pitch lock groove. A larger volume of collar material flows into the locking grooves at the beginning of the of the installation sequence. This gives the fastener its greatest tensile strength where it is most crucial during swaging of the collar so that a high clamp force can be developed with out loss of strength during collar extrusion resulting in a high residual clamp and high ultimate tensile. The locking groove’s 20-degree flank angle serves as a platform for retaining the high clamp load generated during collar installation.
Cost effective Features
Sloped surface installations
The GP™ fastener can be installed on sloped surfaces up to 7° on the collar side of material being fastened. With this feature heavy, costly self-aligning washers and special nuts are not required. Inventory costs as well as structural weight is reduced. Fewer parts to handle translate into greater labor efficiency.


Extended grip range
The GP™ fastener has a usable 3/32" grip range, which reduces inventory, and installation errors that are common when using conventional 1/16" grip range fasteners. The extended grip range makes the GP™ fastener more forgiving if the installer needs a fastener just over or just under the recommended grip.
The labor-intensive job of over-coating each fastener or the use of heavy, costly sealing nuts is eliminated with the GP™ fastener. Annular grooves on the pin forms a series of separate barriers to prevent fuel leaks. Fay surface sealant flows during installation due to high clamp load ensures reliable sealing.
Quiet Interference-Fit Installations
The GP™ can be used in interference applications without noisy rivet hammer insertions. Huck's pull-in installation method reduces noise levels by as much as 50% to 50 dBA when installations are made with hydraulic tools and 75 dBA when using pneumatic tools.

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