Abstract: A medical device includes an elongate body having a proximal end and a deflectable distal region, a handle coupled to the proximal end, an actuator movable relative to the handle, and a resistance assembly adjacent the actuator. The resistance assembly exerts a force on the actuator that varies according to a direction in which the actuator is moving relative to the handle. For example, the resistance assembly can exert a lower (or zero) force when the actuator is moving relative to the handle in a direction that effects deflection of the distal region of the elongate body from neutral and higher when the actuator is moving relative to the handle in a direction that effects return of the distal region of the elongate body towards neutral. The resistance assembly can also include materials that exhibit anisotropic frictional properties and/or have surface finishes or treatments that yield directionally-dependent frictional forces.

Abstract: Methods and apparatus for preloading a bearing are provided. These methods and apparatus include preload monitoring devices whereby the mechanic can accurately monitor and regulate the preload on a bearing or bearing assembly. Aspects of the invention may also be used to adjust the endplay on a bearing or a bearing assembly. In one aspect, the preload on the bearing is transmitted through a housing having a fluid pressure that can be detected and monitored. An apparatus for precisely rotating a nut and a tool for precisely rotating a nut are also provided. A bearing retaining nut arrangement that permits the loading or evaluating of a bearing inner race is also provided. The bearing retaining nut arrangement includes a first load-setting nut, a lock washer, and a second jam nut that secures the arrangement to a shaft.

Abstract: A tensioning system for tensioning a stud is provided. The system includes an adapter ring having an external surface, an internal surface engaging the external surface of the stud or puller screw, and at least two bores defined therein. The posts have first and second ends and are disposed in the bores. The first ends are supported by a stop surface, and the second ends extend outwardly from the bores. A cylinder includes an internal surface engaged with the external surface of the adapter ring. First and second pistons are movably positioned within the cylinder with an intermediate cap disposed therebetween to define first and second hydraulic chambers. The first piston is configured for being supported by the second ends of the posts. The hydraulic chambers are hydraulically connected to one another, whereby providing a hydraulic fluid in the chambers operates to apply a tension force on the stud.

Abstract: A connection between a first component and a second component is provided including a first hole formed in a portion of the first component and a second hole formed in a portion of the second component. The second hole is aligned with the first hole. A pin includes a through hole having a pin hole diameter. The pin extends through a portion of the first hole and into a first portion of the second hole. The pin is configured to absorb a shear load applied to the connection. A bolt extends through the second hole and the pin such that a clearance fit is formed between the bolt and the pin. The bolt is configured to absorb an axial load applied to the connection. A nut connected to the free end of the bolt limits movement of the bolt relative to the first and second component.

Abstract: A generator stator core through-bolt tensioning device that automatically tightens the nut on the through-bolts that hold together and compress laminate plates of the stator core in a high voltage generator. A controller receives a signal from a measuring device, such as a fiber Bragg grating that measures the strain on the bolt, and based on that signal determines whether the nut needs to be tightened. If the controller determines that tightening is necessary, it will cause the tensioning device to automatically tighten the nut while the generator is in service, and use the measuring device to provide feedback of the tensioning of the through-bolt to know when to stop the device from tightening the nut.

Abstract: An apparatus for providing a load on a bearing mounted to a shaft includes an attaching member and a press mechanism. The attaching member is releasably connected to the shaft. The press member is coupled to the attaching member and is configured to provide a compressive load to the bearing. The press mechanism includes an aligning arm configured to engage a shaft slot of the shaft to align the press mechanism relative to the shaft when the attaching member connects to the shaft. A lock nut is engageable with the shaft and has a plurality of engaging teeth configured to engage a plurality of keeper teeth of a keeper.

Abstract: A coupling device provides a pre-tensioned coupling between a first member and a second member. The members are arranged to define a sealed compartment. A piston is housed within the compartment and is translated between the first member and the second member. A first ratchet lock is mounted within the second member and on translation of the piston, the first ratchet lock engages with the piston. A second ratchet is mounted within the second member and, on translation of the piston into the second member, the piston engages with the ratchet. The second ratchet is mounted on a piston, and translation of the second ratchet on the piston applies a tensile force to the first piston to tension or pre-tension the piston. As the ratchets substantially prevent reverse movement of the piston, the tensile force is retained.

Abstract: A two-piece locking nut assembly for securing a mantle to a head assembly of a cone crusher. The two-piece locking nut assembly includes an inner nut and an outer nut. The inner nut includes a set of axial bores that each receive a jackscrew. Once the locking nut assembly is in position on the head assembly, the series of jackscrews are tightened to exert a force on the mantle that is counteracted by forces through the inner nut and into the head to create a locking force between the locking nut assembly and the head assembly. The outer nut is turned along the inner nut to hold the locking nut assembly in place. Once the outer nut is moved into position, the jackscrews are removed such that the outer nut continues to apply the locking force between the mantle and the head through the locking nut assembly.

Abstract: An interlocking nut and washer system complies with new standards identified in the Society of Automotive Engineers (SAE) Recommended Practice J2535, Setting Preload in Heavy-Duty Wheel Bearings, and with maintenance recommendations issued by the Technology Maintenance Council (TMC) Recommended Practice RP618, Wheel Bearing Adjustment Procedure. The system includes an improved inner washer, adjustment nut, intermediate washer, and outer nut that interlocks with the intermediate washer following the introduction of an established level of preload force by the adjustment nut. The inner washer isolates the adjustment nut from the inner bearing race to eliminate frictional wear. An increase in outer diameter of the inner washer provides an interference capability that serves as a safety factor to prevent separation of the wheel hub from the axle spindle in event of bearing failure. The inner washer includes markers to establish the final adjusted preload or the endplay position of the adjustment nut.

Abstract: An apparatus for providing a load on a bearing mounted to a shaft includes an attaching member and a press mechanism. The attaching member is releasably connected to the shaft. The press member is coupled to the attaching member and is configured to provide a compressive load to the bearing. The press mechanism includes an aligning arm configured to engage a shaft slot of the shaft to align the press mechanism relative to the shaft when the attaching member connects to the shaft.

Abstract: This invention relates to a method for hydraulically tensioning screw bolts as well as to screw bolts and screw bolt tensioning devices for carrying out the method. It is proposed to apply the total pretensioning force for one part via an external thread and for the remaining part via an internal thread of the bolt end.

Abstract: A hydraulic nut for tensioning an assembly comprises a mechanical threaded locking collar to minimize load loss during transfer of hydraulic load to the locking collar, an annular piston, an annular pressure area to generate an axial load under hydraulic pressure, a hydraulic pressure port and preferably metallic seals to maintain the hydraulic pressure within the annular pressure area that operates in an elastic region and continues to actuate hydraulic pressure after repeated operating temperature cycles. The seals of the hydraulic nut have a ‘U’ or ‘C’ shaped cross-section.

Abstract: The invention relates to a ring (120) that is intended for being mounted tightly around a shaft of a hydraulic machine to form a portion of a hydrostatic or hydrodynamic bearing. The ring includes at least one first section (122), at least one second section (124) and means (132) for mounting the first and second sections around the shaft. Each section (122, 124) includes two edge surfaces (1223, 1243) connecting the external (1221, 1241) and internal (1222, 1242) radial surfaces thereof. The first section (122) is provided with at least one threaded hole (127) accessible via an edge surface (1223) and capable of receiving a screw (132) projecting from an edge surface (1243) of the second section (124). The screw (132) is provided, on the portion of the shank (134) thereof that projects from the second section (124), with at least one raised pattern (140) for rotatably moving the shank (134) in order to screw or unscrew the shank in the threaded hole (127).

Abstract: A low torque tension relief system for threaded fasteners comprises an inner body with two sloped surfaces, upper and lower wedges which convert longitudinal movement of the inner body to a dimension change in the transverse direction, an outer body which acts to inhibit said movements, and a restraining bolt which passes through the outer body and engages the inner body thereby anchoring said inner body with said outer body and selectively restricting or promoting relative movement of said inner body compared to said outer body.

Abstract: Different embodiments of hydraulic nut are described comprising a pressure system with screws that may be displaced to an end detent, and once the travel of the screw has finished, there is no possibility of a further forward movement thereof, so there cannot be a hydraulic fluid leakage. The hydraulic wrench of the present invention may be used in a preventive way, since the nut may indicate a decrease or increase in the preset stress to which it must operate, or it may indicate that the stress at which it must be installed has been reached. For example, the nut may comprise a visual alarm device, an acoustic alarm device or it may issue a warning signal through phototransistors or radiofrequency.

Abstract: Methods and apparatus for preloading a bearing are provided. These methods and apparatus include preload monitoring procedures and devices whereby a mechanic can accurately monitor and regulate the preload on a bearing or bearing assembly. Aspects of the invention may also be used to adjust the endplay on a bearing or a bearing assembly. The methods and apparatus allow the mechanic to apply and/or verify a preload on the bearing, for example, to apply and/or verify a preferred “3 thousandths” preload, as is desired in the industry. In one aspect, the preload on the bearing is transmitted through a housing having a fluid pressure that can be detected and monitored.

Abstract: Load-bearing ring (120, 220) have segments (121, 122, 221, 222) connected by studs (123) or frangible portions (228), where opposed tapered faces (125, 126, 225, 226) co-operate with complementary faces (114, 115) on hydraulic fasteners (110, 210) on a tapered face (342) on a washer (341), to enable controlled release of the load-bearing rings (110, 210) to enable de-tensioning of a bolt or stud tensioned by the hydraulic fasteners (110, 210, 310).

Abstract: A tensioner for tensioning foundation bolts generally used in securing large utility towers is provided. The tensioner generally comprises a hollow outer body through which the foundation bolt can extend. The lower end of the body, which is adapted to abut onto the foundation surface from which the bolt extends, is provided with an opening allowing access to a foundation nut threaded onto the foundation bolt. The upper end of the outer body slidingly receives therein an inner body with which it defines an annular hydraulic piston, the inner body being configured with a seat portion for receiving and engaging a split nut mounted to the foundation bolt. Upon providing hydraulic fluid to the tensioner, the hydraulic piston urges the split nut, engaged to the foundation bolt, upwardly, thereby tensioning the foundation bolt. The load in the bolt is then maintained by threading down the foundation nut until it abuts onto the foundation surface.

Abstract: A system for providing a load on a bearing mounted to a shaft includes an attaching member and a press mechanism. The attaching member is releasably connected to the shaft. The press member is coupled to the attaching member and is configured to provide a compressive load to the bearing. The press mechanism includes an aligning arm configured to engage a shaft slot of the shaft to align the press mechanism relative to the shaft when the attaching member connects to the shaft. A lock nut is engageable with the shaft and has a plurality of engaging teeth configured to engage a plurality of keeper teeth of a keeper. The nut includes an outer surface having a plurality of markings corresponding to a plurality of roots of the plurality of engaging teeth to allow a user to selectively rotate the nut relative to the aligning arm to an engaging position such that a radially inner side of the keeper engages a slot of the shaft when the keeper teeth engage the engaging teeth of the nut.

Abstract: A pressure enclosure includes a first component having an opening, a second component coupled to the first component in a position over the opening, a third component positioned between the first and second components and covering the opening, and a load chamber defined by a space between the second and third components and configured such that pressure in the load chamber biases the third component against the first component to seal the opening. The pressure enclosure may be a cylinder of a pump for pressurizing fluid or gas, with the first component a cylinder body, the second component an end cap and the third component a valve body, with the load chamber biasing the valve body against the cylinder body.

Abstract: An open mat system to reinforce turf includes an anchor arrangement to help secure the mat to the turf. The anchor arrangement includes an anchor head embedded in the earth, a cable connected to the anchor head, a cable connector device, and a brace. The cable is inserted into the connector device, which holds the cable against withdrawal from the connector device. The brace includes a receiver, in which the cable connector device is removably oriented in the receiver.

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 method of establishing and checking the axial preload in a tightening portion (34) of at least one shank of the screw or stud type (4). The establishing of the preload involves a step of tensioning an extension portion (33) of the shank (4) comprising the tightening portion (34) using a shank (4) gripper member (9) and a tensioner (6). The checking method involves a step in which, prior to establishing the preload, the tensioner is brought into a rest configuration and the gripper member (9) is brought into contact with the tensioner (6) in said rest configuration, and a step in which, having established the preload, the tensioner is returned to said rest configuration, and the tensioner in said rest configuration is pressed toward one of the ends of the extension portion (33) and the difference between the initial length (Li?) and the final length (Lf?) of the extension portion (33) is compared against a threshold.

Abstract: The invention relates to a blind rivet and a rivet pin that is connected or can be connected to the tool and is used to apply the blind rivet. Said rivet pin can be connected, by means of a rivet positioning tool, to a part of the blind rivet designed for said tool. When the blind rivet is inserted into a hole up to the abutment of an abutment shoulder formed on a flange, said contact place can be lengthened by means of the rivet pin acting as a traction element, in order to deform the rivet pin such that it fixes in the opening.

Abstract: The present invention is directed to a self locking tensioner that can be used to place a piston or stud in tension. The present invention is directed to a tensioner comprising slip wedges positioned between a piston and a body which houses the piston and the slip wedges.

Abstract: This invention relates to a method for hydraulically tensioning screw bolts as well as to screw bolts and screw bolt tensioning devices for carrying out the method. It is proposed to apply the total pretensioning force for one part via an external thread and for the remaining part via an internal thread of the bolt end.

Abstract: A threaded connection comprising a first threaded member threadably connected with a second threaded member and an axial loading member. The first threaded member defines an opening for passage of the axial loading member therethrough, wherein the axial loading member protrudes from the first threaded member when in an extended position. The second threaded member has a loading surface defining a recess therein for receipt of the axial loading member when in the extended position such that the axial loading member bears on the loading surface and imparts an axial tensile force between the first and second threaded members. A method for connecting the members includes threading together the first and second threaded members, and passing the axial loading member through the opening defined by the first threaded member, so as to bear on the second threaded member within the recess, imparting the axial tensile force between the threaded members.

Abstract: A coupling device provides a pre-tensioned coupling between a first member and a second member. The members are arranged to define a sealed compartment. A piston is housed within the compartment and is translated between the first member and the second member. A first ratchet lock is mounted within the second member and on translation of the piston, the first ratchet lock engages with the piston. A second ratchet is mounted within the second member and, on translation of the piston into the second member, the piston engages with the ratchet. The second ratchet is mounted on a piston, and translation of the second ratchet on the piston applies a tensile force to the first piston to tension or pre-tension the piston. As the ratchets substantially prevent reverse movement of the piston, the tensile force is retained.

Abstract: A fastener comprises a fastener post, a clasping element and an elastic element. The fastener post comprises a head, a post body and a threaded portion. The post body has a first extension section connecting with the head, a second extension section connecting with the threaded portion and a recess section connected between the first and second extension sections. The clasping element comprises an annular clasping body, a first clasping portion axially extending from the clasping body and a second clasping portion extending outwardly and then downwardly from the clasping body. The clasping body encloses the post body, the first clasping portion engages with the recess section of the post body, and the second clasping portion engages with the heat sink. The elastic element is set around the post body and located between the head and the clasping body.

Abstract: A fastener assembly for use in a joint in a work-piece comprises a first fastener component for extending through a hole in the work-piece, a second fastener component and a resilient element. The first component has a first contact portion for engaging the work-piece. The second fastener component has a second contact portion for cooperating with the first fastener component to compressively load the work-piece thereby forming the joint. The resilient element is located between the first and second contact portions so that it is it is compressed under load. The resilient element has a first stiffness characteristic when subjected to loading less than a predefined amount and has a higher stiffness characteristic when subjected to loading more than the predefined amount.

Abstract: The present invention is directed to a self locking tensioner that can be used to place a piston or stud in tension. The present invention is directed to a tensioner comprising slip wedges positioned between a piston and a body which houses the piston and the slip wedges.

Abstract: A rivet fixing device includes a catch tab retainer tube engageable with a transmission spindle of an electrically-operated, pneumatic or battery-powered electric drill or screwdriver, an inner guide sleeve, a driver, pawls, a rivet breaker, and an outer guide sleeve. By being driven by the transmission structure of the electric screwdriver, a rivet, with a shank section thereof inserted into a front end of the rivet breaker and the rivet being fit through holes defined in steel plates, iron plates, copper plates, or aluminum plates, due to the catch tab retainer tube being depressed inward to engage the transmission spindle, is driven by the rearward movement of the catch tab retainer tube to have a fit end thereof that extends beyond the holes of the plates squeezed and deformed to form an expanded portion, serving as a positioning wall that stretches and secures the rivet between the two metal plates.

Abstract: A fastener includes a threaded circular ring half divided along a plane intersecting a central longitudinal axis. One of the end walls is formed with a truncated conical load-bearing surface that is seated on a truncated conical thrust surface formed on a circular ring of a stress generator. The load bearing and thrust generating surfaces are arranged to present a conjugate pair of truncated conical surfaces to provide a favorable resolution of forces developed by torque applied to jack bolts distributed about an outwardly surrounding cylindrical stress generator body section.

Abstract: The present invention is directed to a self locking tensioner that can be used to place a piston or stud in tension. The present invention is directed to a tensioner comprising slip wedges positioned between a piston and a body which houses the piston and the slip wedges.

Abstract: Methods and apparatus for preloading a bearing are provided. The apparatus includes a rod having a first end and a second end adapted to be removably mounted to a shaft; a device for compressing a hub against the outer race of a bearing to provide the preload to the bearing; and a cylindrical frame positioned between the device for compressing the hub and the hub. These methods and apparatus include preload monitoring devices whereby the mechanic can accurately monitor and regulate the preload to a bearing or bearing assembly. Aspects of the invention may also be used to adjust the endplay on a bearing or a bearing assembly. In one aspect, the preload to the bearing is transmitted through a housing having a fluid whose pressure can be detected and monitored. An apparatus for precisely rotating a nut and a tool for precisely rotating a nut are also provided.

Abstract: Described herein are fasteners and devices for securing together several components so that the load applied to the components is constant or nearly constant. The fasteners described herein include a hyperelastic member having first end to which a first retainer is coupled and a second end to which a second retainer is coupled. The retainers are configured to contact the structures being fastened and transfer the load from the structures to the hyperelastic member. The hyperelastic member may be an elongate shaft (e.g., a rod, cylinder, strut, etc.), and is a shape memory alloy that is typically fabricated as a single crystal.

Abstract: A device integrally formed with a threaded nut or bolt for establishing that a desired minimum preload condition has been attained. The device includes an annular portion including a disk shaped bottoming surface and a top area. A frusto-conical portion circumscribes the annular portion and includes a frusto-conical bottoming surface with an inner smaller diameter abutting the disk shaped bottoming surface and an outer larger diameter spaced longitudinally from the disk shaped bottoming surface. The frusto-conical bottoming surface forms an angle with a plane transverse to the longitudinal of between ten (10) and thirty (30) degrees. The device is preferably made of steel having carbon content of less than 0.3%.

Abstract: Methods and apparatus for preloading a bearing are provided. These methods and apparatus include preload monitoring devices whereby the mechanic can accurately monitor and regulate the preload on a bearing or bearing assembly. Aspects of the invention may also be used to adjust the endplay on a bearing or a bearing assembly. In one aspect, the preload on the bearing is transmitted through a housing having a fluid pressure that can be detected and monitored. An apparatus for precisely rotating a nut and a tool for precisely rotating a nut are also provided. A bearing retaining nut arrangement that permits the loading or evaluating of a bearing inner race is also provided. The bearing retaining nut arrangement includes a first load-setting nut, a lock washer, and a second jam nut that secures the arrangement to a shaft.

Abstract: A double nut for a controlled fixing of a component using a bolt connection, comprising a pulling sleeve having an internal thread adapted to be screwed onto a threaded end of a bolt, and a pressing sleeve adapted to be supported on the component. An internal thread of the pressing sleeve is adapted to be screwed onto an external thread of the pulling sleeve, and engages such external thread to such an extent that the internal thread of the pressing sleeve is spaced by a distance equaling several threads from that end of the pulling sleeve that faces the component. The external thread of the pulling sleeve is furthermore adapted to threadedly receive a pull bushing of a bolt-tightening cylinder that has a support bushing adapted to be supported on the component and to extend over the pulling sleeve and the pressing sleeve.

Abstract: A hydraulic nut having a first part connected around the first end of a fixing member the first part having an annular recess which opens to receive a second part forming an annular member which fits within the annular recess, wherein a pressurized medium chamber is defined between the second part and the annular recess. The second part has an annular portion which extends longitudinally away from the first part. The annular portion has an outer surface which is spaced radially inwardly to form a locking part recess. A locking part is placed within the locking part recess, and has an inner diameter which is threadedly engaged with the second part outer surface. The locking part has a surface facing the first part first surface, and movable by the threaded engagement with the second part to an abutment with the first part first surface.

Abstract: A hydraulic tensioning system for nuts on studbolts has a puller bar and a puller buddy, which are coupled to the studbolt, and a bridge around the nut. The puller bar is internally coupled to the studbolt (and may engage the nut before the tension is applied). The nut can comprise a cone nut, which cooperates with a complementary collar or shell with a conical inner face and a spherical base washer.

Abstract: A system (150) and method of tensioning a bolt (44) across a flange assembly (42). A tensioning apparatus (40) includes the bolt and an unthreaded nut (48) connected to the shank member by an interference fit. The interference fit may be selectively relaxed by applying a fluid pressure to a groove (54) between the nut and the bolt. A tensioner (58) 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 (148) to be used for both functions.

Abstract: A hydraulic nut having a piston which is movable in a fluid chamber of a nut body and which has a radial protrusion from the piston and a displacement bar mounted on the protrusion. The displacement bar overlies the nut body and extends past the nut body by an amount equal to the distance through which the hydraulic nut is to move a bearing assembly along a tapered shaft or move an adapter sleeve, or removal sleeve with bearing assembly on them.

Abstract: A first load-receiving member having a cylinder and a screw hole through which a bolt is thread-engaged and a second load-receiving member having a piston and a fastening face that is made in contact with a member to be fastened are attached to a nut, and a number of balls made of steel the surface of which is lubricated by grease are loaded into a pressure chamber that is formed as a compartment by the cylinder and the piston. Since these balls exert fluidity in the pressure chamber, a load applied to the balls is transmitted to the cylinder and the piston through the balls by screwing the input bolt. Thus, the first load-receiving member is moved in the axis direction with respect to the second load-receiving member, thereby applying a tensile force to the bolt.

Abstract: A tensioning apparatus (40) for applying a closing force across a flange assembly (42). The tensioning apparatus includes a shank member (44) and an annular member (48) connected to the shank member by an interference fit. The interference fit may be selectively relaxed by applying a fluid pressure (P1) to a groove (54) between the annular member and the shank member. A tensioner (58) is used to pre-load the shank member by pulling on the shank member while pushing on the annular member while the interference fit is sufficiently relaxed to allow relative movement between the annular member and the shank member. Once the pre-load is established, the interference fit is reestablished by releasing pressure P1 to lock the annular member in position for maintaining the closure force across the flange assembly after the tensioner is removed. A lock nut (34) may be tightened against the annular member to provide additional protection against the release of the pre-load.

Abstract: A hydraulic tensioning system for nuts on studbolts has a puller bar and a puller buddy, which are coupled to the studbolt, and a bridge around the nut. The puller bar is internally coupled to the studbolt (and may engage the nut before the tension is applied). The nut can comprise a cone nut, which cooperates with a complementary collar or shell with a conical inner face and a spherical base washer.

Abstract: A tensioning apparatus (40) for applying a closing force across a flange assembly (42). The tensioning apparatus includes a shank member (44) and an annular member (48) connected to the shank member by an interference fit. The interference fit may be selectively relaxed by applying a fluid pressure (P1) to a groove (54) between the annular member and the shank member. A tensioner (58) is used to pre-load the shank member by pulling on the shank member while pushing on the annular member while the interference fit is sufficiently relaxed to allow relative movement between the annular member and the shank member. Once the pre-load is established, the interference fit is reestablished by releasing pressure P1 to lock the annular member in position for maintaining the closure force across the flange assembly after the tensioner is removed. A lock nut (34) may be tightened against the annular member to provide additional protection against the release of the pre-load.

Abstract: A system (150) and method of tensioning a bolt (44) across a flange assembly (42). A tensioning apparatus (40) includes the bolt and an unthreaded nut (48) connected to the shank member by an interference fit. The interference fit may be selectively relaxed by applying a fluid pressure to a groove (54) between the nut and the bolt. A tensioner (58) 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 (148) to be used for both functions.

Abstract: A tension control arrangement including a plurality of cams disposed about an opening that accommodates a bolt to which a nut is intended to be secured. Each of the cams has a contoured outer surface, and each of the cams is rotatably supported such that the contoured outer surface operatively engages both the base and a contact member interposed between the cam and the nut. A lever assembly is operatively coupled to the cams, such that movement of the cams is substantially restricted to rotational motion from a first position in which the nut is engaged with the bolt and tightened by hand until it is seated against the contact member, to a second position in which the bolt is elongated to achieve a predetermined bolt tension.

Abstract: A stud tensioning device includes a nut having internal threads and external threads. The internal threads engage corresponding threads on the stud. At least two axial bores are defined by the nut, and posts are disposed in the bores. Each post at a first end thereof engages a stop surface, and at a second end thereof extends external to the bores and axially beyond a free end of the stud in a direction away from the structural member. A load cell threadingly engages the nut applying an axially-directed force on the posts in a direction toward the structural member and on the nut in a direction away from the structural member to thereby tension the stud.