Abstract: A system and method of tensioning a bolt across a flange assembly. A tensioning apparatus includes the bolt and an unthreaded nut connected to the shank member by an interference fit. The interference fit may be selectively relaxed by applying a fluid pressure to a groove between the nut and the bolt. A tensioner is energized by a pressure to pre-load the bolt by pulling on the bolt while pushing on the nut while the interference fit is sufficiently relaxed to allow relative movement between the nut and the bolt. The tensioner is sized to achieve the required pre-load in the bolt at the same working fluid pressure that is necessary to relax the interference fit on the stretched bolt, thus permitting a single pressure source to be used for both functions. Once the pre-load is established, the interference fit is reestablished by releasing pressure to the nut to secure the nut in position for maintaining the closure force across the flange assembly after the tensioner is removed.

Abstract: A hydraulic screw tensioning device for adjusting screws or bolts includes a cylinder supported on a machine part to be clamped by a threaded bolt and nut, at least one piston guided in the cylinder, a change sleeve threaded onto a threaded end of the bolt, a rotary sleeve in the cylinder for positive connection with the nut, first and second gear mechanisms for driving connection with the rotary sleeve and the change sleeve, respectively, a drive motor for the gear mechanisms, a connecting shaft between gears in the second gear mechanism and first gear mechanism, a device for alternative coupling of the drive motor with the change sleeve or the rotary sleeve, and respective recesses or extensions on a gear secured to the change sleeve and on the gear in the second gear mechanism to positively receive a tool for driving the connecting shaft.

Abstract: Axially expandable spacers (51, 53) are insertable between a nut (20), on a bolt (19) to be tensioned, and a face (F) on a component (C) and have ramp faces (52, 54) to take up the space as the bolt (19) is tensioned by an hydraulic tensioner (25), where the puller bar (35) is engaged with an extension (121) on the nut (120). A segmented collar (60) has radially movable segments (61) to allow quick engagement/release between the puller bar (35) and the end of the bolt (19) on the nut (120).

Abstract: A hydraulic screw tensioning device for tightening and loosening highly stressed screws or bolts comprising a cylinder supported on a machine part that is to be clamped by a threaded bolt and nut. A change sleeve is threaded onto a threaded end of the bolt. A first annular piston is guided in a sealed manner in a cylinder element, is disposed on the change sleeve, and is supported against an inclined surface of a monolithic collar of the change sleeve. At least one second annular piston is guided in a sealed manner in a cylinder element, is disposed on the change sleeve, and is supported against the first annular piston. Respective, facing inclined axial annular surfaces on the annular pistons and on the cylinder elements or annular shoulders thereof are inclined in the same direction and are pressure-remote. Annular surfaces on the second annular piston or pistons and on the annular shoulders of the cylinder elements extend perpendicular to the cylinder axis and are pressurized.

Abstract: The invention relates to a device for tensioning a threaded rod (1). The inventive device comprises: an actuator (5) which can exert an axial force; and a tie rod (6) which transmits the axial force from the actuator (5) towards a threaded end (1b) of the rod (1b), said tie rod (6) comprising at least two jaws (31) which can move radially between a closed position, in which the tie rod (6) is engaged with a threaded end (1b) of the rod (1), and an open position in which the jaws (31) are disengaged from the threaded rod (1b). Moreover, said device comprises a locking element (45) which can move between a jaw (31) opening position and a jaw (31) closing position.

Abstract: An axial-force-detective fastening tool fastens a nut to a bolt, and at the same time, detects and axial force acting on the bolt. The tool has a socket body rotatably supported with a tool body and having a nut receiver. The socket body turns a nut received in the nut receiver around an axis of the socket body, to fasten the nut to a bolt. An ultrasonic sensor is supported with the tool body, is movable along an axis of the socket body, and is brought into contact with a front end of the bolt in the nut receiver. The ultrasonic sensor emits and receives ultrasonic waves to detect an axial force acting on the bolt. A sensor spring pushes the ultrasonic sensor to the front end of the bolt. The bolt includes a reference surface which is engaged by the ultrasonic sensor and is recessed in a tapered opening in an end of the bolt.

Abstract: A washer which has a body having a first bearing face surface at one axial side and adapted to cooperate with a nut, a second bearing face surface at an opposite axial side and adapted to cooperate with an object, at least one third turning resistant surface adapted to cooperate with a thread of the bolt, and at least one breaking point arranged so that when the nut is turned and turns the bolt the washer stops the bolt from turning and thereby the nut creates a pull on the bolt which elongates the bolt in an axial direction and applies to the washer an axial force which breaks said body of the washer and allows a portion of said body of the washer to be pulled axially when the bolt elongates; and also a fastener, a method of fastening objects, and a tool for fastening objects can be provided with the new washer.

Abstract: An apparatus (10) for tightening a hexagon head bolt (13) includes a vertically movable automatic robot arm (16), a screwing mechanism (18) having a rotational part (19), a shaft member (20) mounted to the rotational part, a socket portion (21) mounted to the shaft member for receiving therein a head (14) of the bolt, and a retention means (22) for retaining the head received in the socket portion or retaining the head released from the socket portion. When the arm moves vertically with the head received in the socket portion, the rotational part is rotated along with the shaft member and the socket portion to screw the bolt into a threaded aperture (12) of a crankcase (11) of an engine.

Abstract: For assembling at least two parts of an object with one another, a bolt having a thread is introduced into the parts, a washer is placed on a free end of the bolt, a nut is threadingly connected to the free end of the bolt so as to abut against the washer, a power tool is placed so as to turn the nut by a rotatable element of the power tool connected to the nut to tighten or loosen the bolt and to apply a non-rotatable element of the power tool to the washer to absorb reaction force and the body of the washer is provided with a breaking point such that when the nut is turned and turns the bolt, the washer stops the bolt from turning and thereby the nut creates a pull on the bolt which elongates the bolt in an axial direction and applies to the body of the washer an axial force which breaks a portion of the body of the washer and allows a portion of the body of the washer to be pulled axially when the bolt elongates.

Abstract: A method of tightening and loosening an object to a rotary base torsion-free includes providing a single power tool having a tool housing portion and a driving portion which are coaxial with one another and provide equal but opposite forces, connecting a bolt with the rotary base, connecting a first part which includes a sleeve/washer assembly to one of the portions to be turned by the one portion, which sleeve/washer assembly includes a sleeve with a thread cooperating with a thread of the bolt and a washer abutting against the object, connecting a second part to the other of the portions to be turned by the other portion, which second part includes a nut having a thread cooperating with another thread of the first part, turning the first part by the one portion so that the first part, the bolt and the rotary base turn together while the second part remains free of rotation to urge the bolt to move in a desired axial direction to tighten or loosen the object to the rotary base, and turning the second part by

Abstract: A pressure vessel having a removable closure head in a high radiation environment is closed by placing the closure head having a flange over and spaced from the flange of a pressure vessel body containing fissile material. The closure studs are installed in closure stud holes of the pressure vessel body flange. Transition nut members of hydraulic nut assemblies are threaded onto the closure studs. Hydraulic hoses are connected between the hydraulic nut assemblies and a pressure source. The pressure source simultaneously pressurizes the hydraulic nut assemblies to simultaneously apply a uniform force to the closure studs sufficient to seat the spaced apart closure head flange on the pressure vessel body flange and to elongate the closure studs. The hydraulic nut assemblies are locked in place over the closure head flange while the force is applied to the closure studs and the closure studs are elongated.

Abstract: A method and apparatus for connecting underwater conduits and more specifically, to a method and apparatus which is capable of performing the diverless connection of underwater flowlines and connection of these flowlines to underwater structures such as flowline bases, xmas trees, and templates. The connection of underwater conduits is facilitated by the use of a remotely operated vehicle and connection apparatus both being launchable and recoverable by a support vessel. The connection apparatus adapted to mount on at least one of the underwater conduits and the connection apparatus allowing for docking of the remotely controlled vehicle which then captures and draws a second conduit to form a continuous flowline. Then a connection apparatus is clamped upon the conduits. The apparatus then bolts the conduits together.

Abstract: A high temperature bolting system for clamping steam turbine housings and similar high temperature parts together while operating at a temperature of 800° F. to 1200° F. An elongated fastener shank and housing material have similar coefficient of thermal expansion. The shank has a tensile strength several times greater than the housing to maintain a clamping force during thermal excursions. The diameter of the shank is reduced due to the large creep strength difference between the elongated fastener shank and the clamped parts. The reduced shank diameter allows an increased in the clamping load by providing an increased surface area in the clamped part. A stress generating flange is provided with jackbolts to establish the clamping load at room temperature. A threaded sleeve is interposed between the threads at the end of the shank and the threads of the housing so that the housing threads have a sufficiently large area for withstanding the clamping load.

Abstract: The invention relates to a method and a device for producing screw assemblies, which can be preferably used in industrial production assembly processes, in workshops and in installation technology supervision involving high safety standards. The invention also relates to special screws to carry out said method. The invention is characterized in that the actual elongation of the screw is measured during screwing.

Abstract: Jackbolts for multi jackbolt tensioner embody a thread construction which taper from a maximum diameter adjacent to torque receiving end of the jackbolt when threadedly engaged with a threaded opening in the outer peripheral part of a jackbolt body. The threads of the jackbolt have a different thread pitch than the threads in the jackbolt body and the tooth flank of the jackbolt threads for an angle with the tooth flanks of the thread in the jackbolt body. By this thread construction, there is formed a helical volume of ever increasing size along the jackbolts commencing at a metal to metal relation at the torque receiving end. Stressing of the jackbolt closes the helical volume bringing the threads to a metal to metal load transfer relation. The end of the jackbolts has a protruding central end portion that elastically flattens under stress to reduce torque requirements.

Abstract: A high temperature bolting system for clamping steam turbine housings and similar high temperature parts together while operating at a temperature of 800° F. to 1200° F. An elongated fastener shank and housing material have similar coefficient of thermal expansion. The shank has a tensile strength several times greater than the housing to maintain a clamping force during thermal excursions. The diameter of the shank is reduced due to the large creep strength difference between the elongated fastener shank and the clamped parts. The reduced shank diameter allows an increased in the clamping load by providing an increased surface area in the clamped part. A stress generating flange is provided with jackbolts to establish the clamping load at room temperature. A threaded sleeve is interposed between the threads at the end of the shank and the threads of the housing so that the housing threads have a sufficiently large area for withstanding the clamping load.