Abstract: A tool for installing an externally threaded and keyed insert comprising a mandrel for the acceptance of an externally threaded insert. A cylindrical key-set sleeve is journaled on the mandrel and is movable axially thereof so as to bias the keys on the insert to the locked condition. An air chamber supports a piston that is movable upon the introduction of pressurized air into the air chamber to effect locking movement of the key-set sleeve.

Abstract: A co-axial, dual trigger valve mechanism for use in a nut runner, said valve mechanism being of such a construction as to permit low air flow initially so as to deliver only minimum acceptable torque to the nut with the result that the tool is caused to stall out at this low flow in cases where the nut has been properly pre-crimped and then upon further depression of the trigger full air flow will result causing the nut to be fully and properly installed. Conversely, if the nut has not been properly pre-crimped, the initial depression at the low pressure will cause the nut to be fully run all the way down thus indicating to the operator that the nut is improper and must be removed and replaced.