DESCRIPTION
The GB7720 is a hydraulic installation designed to install 5/8" Bobtail® lockbolts. It weighs 15 lbs and has a
1.900" rivet setting stroke and a rated pull load of 21,000 lbs. at 5,000 psi PULL pressure.
The GB7720 installation tool is designed to operate at pressures up to 10,000 psi on hydraulic pressure developed
by the Powerunit. Normal operating pressure is set at 5,000 psi PULL pressure and 4,000 psi RETURN pressure,
enabling the tool to pull 5/8" Bobtail® lockbolts. The powerunit pressures may be set using 942280 pressure
setting gauge. The tool comes equipped with 24" hoses and electric cord kit complete with quick disconnects.
BT20-7720-58 NOSE ASSEMBLY MUST BE ORDERED SEPARATELY.
OPERATION
When the tool is connected to a powerunit, operation is controlled by a button in the handle. When the
button is depressed, a directional valve in the powerunit directs fluid to the front side of the piston
forcing it and the nose assembly puller rearward. This action causes the jaws to clamp onto the fastener
pintail and pull the sheets together. The anvil is forced forward, swaging the collar into locking grooves
of the fastener.
When the button is released the directional valve reverses fluid flow to the back of the piston and
pushes the nose assembly off of the swaged fastener.
MAINTENANCE
The performance of any tool depends upon good maintenance practices. Following these minimal
requirements for service and care will extend the life of your tool.
*Only use a hydraulic power source equipped with relief valves and pressures set within specified
limits.
*Keep hydraulic system free of dirt. Avoid letting couplers contact a dirty floor.
*Do not use as a hammer to force fasteners into holes or otherwise abuse tool.
*Proper care by operators is necessary in maintaining full productivity and reducing downtime.
WARNING
Be sure powerunit is disconnected before cleaning, or when replacing worn or damaged components.
Severe personal injury may occur if power source is not disconnected.
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