According to a first aspect of the invention we provide an automatic reaction pawl-assembly (ARPA) which includes; a shaft assembly; a pawl fixed rotatably relative to the shaft assembly; and a torsion lever torsionally coupled with the paw) about the shaft assembly. Advantageously the ARPA enhances belting efficiency, increases torque accuracy and maximizes operator safety. Torsion springs of the shaft assembly overcome a housing spring and automatically disengage the pawl from a ratchet wheel. The pawl releases without advancing the fastener, touching the tool or raising the hydraulic pressure beyond an intended torque value. This allows for hands free operation of one or more tools. During SWULTORC the operator no longer needs to determine which tool; is locked on to its fastener.

A reaction arm for use with a torque generating device, the reaction arm including a reaction bar, and a body portion having a first internal diameter, and having formed on an internal surface thereof a female spline having a second internal diameter and a guide bushing having a third internal diameter, the first, second, and third internal diameter being distinctly sized.

A hand-held knockout driver includes a main housing having a handle portion, a motor positioned within the main housing, a hydraulic assembly driven by the motor and including a reservoir containing hydraulic fluid, a secondary housing coupled to the main housing and defining a bore therein, a working piston moveable within the bore between a rest position and an actuated position, and a work zone defined between the secondary housing and the working piston into which pressurized hydraulic fluid discharged from the hydraulic assembly is received. One unit of fluid is added to the work zone to move the working piston from the rest position to the actuated position. The reservoir has a fill capacity no greater than about 1.5 units of fluid.

Torque tools of the present invention include: a hydraulic cylinder assembly (40); a drive assembly (600, 60); a flexible linkage connection, or force transfer, assembly formed between the hydraulic cylinder assembly (40) and the drive assembly (600, 60); all of which is formed within or adjacent to a housing assembly (70). They provide large, accurate torque for limited clearance applications. The flexible linkage connection assembly (50) includes a rocker arm assembly (51) and a chain link-pin assembly. The flexible linkage connection assembly (50) maintains the relationship between the line of action of the linear force generated on the rocker arm assembly (51) by the hydraulic piston assembly (44, 50)(ies) and rotary force generated on the ratchet drive socket (9) by the rocker arm assembly (51) via the chain link-pin assembly at close to the optimized position throughout the entire travel of a drive plate assembly (61) of the drive assembly (600, 60). The resulting efficiency increase of converting linear force and displacement into rotary torque and angular displacement allows for generation of large and accurate torque in minimal cross-sections necessary to access hidden, limited clearance and/or inaccessible threaded fasteners.

A torque wrench assembly includes a torque wrench head being adapted to both tighten and loosen a fastener, wherein the torque wrench head includes fastener engaging means and drive means for driving the fastener engaging means. The torque wrench assembly also includes means for mounting the torque wrench assembly on a support means, wherein the torque wrench head and the mounting means are adapted so that the torque wrench head is capable of both tightening a fastener and loosening a fastener.

A ratchet wrench includes a body having a head and a shank interconnected to the head. The head includes a driving hole extending along a first axis and receiving a driving device. The shank includes a transmission hole receiving a transmission shaft. An axis fixing device is mounted in a transmission groove between the driving hole and the transmission hole and includes an axial hole extending through the axis fixing device along a second axis that extends perpendicularly to and intersects with the first axis. A gear coupled to the driving device is received in the axial hole and is rotatable about the second axis. A driving end of the transmission shaft extends into the axial hole and is connected to the gear.

A limited clearance hydraulic tool provides torque to an associated threaded fastener assembly. The limited clearance hydraulic tool includes a piston and a rachet wheel. The limited clearance hydraulic tool also includes a drive plate and a piston rod extending between the drive plate and the piston. The limited clearance hydraulic tool further includes a connection pin that defines a first point of contact between the piston rod and the drive plate and continuously connects the piston rod and the drive plate together to always drive and retract the drive plate. Additionally, the limited clearance hydraulic tool includes a push plate that defines a second point of contact between the piston rod and the drive plate. The push plate is separate and unique from the first point of contact. The push plate selectively connects the piston rod and the drive plate together for driving the drive plate.

A safety wrench for coupling and uncoupling hammer union type connections employs a spring biased retractable bolt to apply a blow to the union lug. In use the bolt is retracted rearward to compress compression springs positioned within an internal spring bore in the bolt to a position away from the lug of the union to be rotated. When the bolt is disengaged from the ratchet mechanism, the compression springs rapidly extend to rapidly move the bolt forward to impact the union lug and rotate the union. The bolt may be retracted by a hydraulic or pneumatic cylinder, a hand lever, or a rack and pinion mechanism. Reversing the position of the safety wrench on the union lug will allow the union to be rotated in the opposite direction.

Apparatus for use in operations of tightening and/or loosening threaded fasteners of the kind having a nut and stud about an axis are disclosed and include: a threaded assembly threadedly engageable with exposed threads of the stud above the nut and either a nut, a tool socket and/or a tool housing engagement assembly. Torque tools of the kind having a pass-through socket including the apparatus are disclosed. And systems including the torque tools of the kind having a pass-through socket including the apparatus and threaded fasteners are disclosed. Advantageously holding plate assemblies of the present invention: allow torque tools and/or drive extension links with through sockets to be used in vertical, inverted and/or tight clearance bolting applications; allow for simultaneous operation of multiple such tools on such bolting applications to achieve Parallel Joint Closure; account for bolting application having long and/or protruding studs; and increase bolting speed and safety, efficiency, reliability and repeatability.

In a torque wrench system with a drive unit (2) and a ratchet unit (3), which can releasably be assembled to a wrench unit, wherein drive unit (2) and ratchet unit (3) releasably are rigidly connected with each other in the assembled condition, the drive unit (2) includes a first drive coupling element (5) and the ratchet unit (3) includes a ratchet (18) and a second drive coupling element which is in driving engagement with the ratchet (18) and, in the assembled condition of drive unit (2) and ratchet unit (3), also with the first drive coupling element (5) for driving the ratchet (18), the drive unit (2) includes at least one latch (7) which is movable from an unlocking position, in which the drive unit (2) and the ratchet unit (3) are releasable from each other, into a locking position, in which the drive unit (2) and the ratchet unit (3) are rigidly connected with each other in the assembled condition, and back, and at least one actuating element (9) with which the at least one latch (7) is movable from the one into the other position, and the ratchet unit (3) includes a latch receptacle (23) which is in locking engagement with the latch (7) in its locking position for rigidly connecting the drive unit (2) with the ratchet unit (3) in their assembled condition.