A method for installation and/or maintenance of a flange connection includes screw connections with a manually movable tool including a screw tensioning structure, a processing unit and a screw identification sensor. The method includes assigning a one-to-one identification to each screw connection of the flange connection, determining a screw connection to be tensioned, positioning the tool on a respective screw connection to be tensioned, identifying the respective screw connection by the screw identification sensor, releasing the screw tensioning structure by the processing unit, and tensioning the respective screw connection by the screw tensioning structure. It is checked whether the tool or the screw tensioning structure is placed correctly on the screw connection. The screw tensioning structure is released when the result of this check is positive and/or the screw tensioning structure is blocked or stopped when the result of this check is negative.

A tensioning apparatus is adapted to simultaneously tension a number of jackbolts of a multi jackbolt tensioner. The tensioning apparatus may be made compact by overlapping gear disks of the spindle gears and further act as a torque multiplier between the other gears of the tensioning apparatus. The tensioning apparatus can be part of a combination with a power transfer assembly.

The present technology relates to a battery cell jig for fastening bolts with uniform pressure when fixing a battery cell between first and second plates by applying the same rotating force to a plurality of bolt fastening units. The battery cell jig includes first and second plates arranged to face each other, n bolt fastening units, where the n is an integer equal to or greater than 2, a rotating member which is installed on one surface of the first plate or the second plate and is installed on an opposite side of a surface where the first and second plates face each other, and a driving unit which transmits rotating force of the rotating member to each of the n bolt fastening units.

In a tightening method for a screw connection of a bolt and a nut by using a tensioning device, a rotary drive, and a process control unit with documentation module, the nut is tightened with the rotary drive by a tightening moment required for the nut to bear against a support. The screw connection is elongated by exerting axial tension on a threaded end of the bolt protruding from the nut. The nut is further tightened while maintaining elongation, and a rotation angle covered during further tightening is detected by a rotation angle sensor. Lengthening of the bolt is calculated from the rotation angle and thread geometry of the screw connection. A longitudinal force in the threaded bolt is calculated from lengthening of the bolt, bolt diameter and bolt length. The calculated longitudinal force and an identifier identifying the screw connection are stored in the documentation module.

A bolt tensioning assembly has a bolt with a first end portion and a second end portion at an opposite side of the bolt. The first end portion has an enlarged diameter to form a counter-pressure surface facing the second end portion. The first end portion has external threads to receive a lock nut. A hydraulic bolt tensioning device is for tensioning of the bolt. The hydraulic bolt tensioning device is arranged for enclosing a portion of the bolt such that it abuts the counter pressure surface. A lock nut is arranged on the first end portion of the bolt. The hydraulic bolt tensioning device and lock nut are dimensioned such that upon tightening of the lock nut, the lock nut will tighten against a portion of the hydraulic bolt tensioning device.

A fastening device for fastening a bolt to a fastening target object, wherein the bolt has a bolt head female screw section in an inner circumferential surface of a recess provided in an upper surface of a bolt head section. The fastening device includes a tension rod having a rod male screw section engaging the bolt head female screw section; a drive socket circumferentially surrounding the tension rod and having a lower end section with a grasper for laterally grasping the bolt head section; a supporter circumferentially surrounding the drive socket and having a lower end section protruding downward beyond a lower end section of the drive socket; a sensor for sensing compression force acting on the supporter in the upward/downward direction; a first motor for rotating the tension rod around an axis extending in the upward/downward direction; and a second motor for rotating the drive socket around the axis.

A tensioner may assist in coupling two pipe flanges. The tensioner may include a body and a piston. The body may include a central longitudinal axis, a pair of fastener holes extending through the body in a direction parallel to the central longitudinal axis, and a piston housing having an inner bore disposed about the central longitudinal axis. The piston housing may be provided between the pair of fastener holes. An axial end of the piston housing may define a distal end of the body. The piston may be at least partially disposed in the inner bore of the piston housing. The piston may be axially moveable parallel to the central longitudinal axis through an opening of the inner bore at the distal end of the body.

The present invention relates to a multi jackbolt tensioner and methods of using the same. The present invention alleviates some of the problems associated with presently available multi jackbolt tensioners.

Embodiments disclosed herein generally relate to a system and method for tensioning a bolt. The bolt tensioning system may be used with variable length connection members, for example studs, in any one or more of the drilling, subsea, and process industries to couple a first member to a second member. The bolt tensioning system may remain coupled to the first member and the second member, while applying tension to all of the bolts at the same time, rather than having to torque or tension each bolt individually. The bolt system may accurately and uniformly tension all bolts in a single operation to provide reliable connections.

The invention concerns a rod tensioning device having a first actuator, at least a second actuator and a tubular support sleeve dedicated to radially surround a threaded rod. Each of the actuators provides a cylinder, and a piston sliding in the cylinder and forming with the cylinder an annular chamber dedicated to be supplied with pressurized fluid. According to the invention, the at least second actuator is temporary axially arranged between the first actuator and the tubular support sleeve for a temporary blockwise assembly, the pistons of two axially adjacent actuators being indexed in rotation together.