Disclosed is a method of tensioning/detensioning closure studs of a nuclear reactor vessel. The closure studs are spaced about a circumference of the reactor vessel so as to attach an integrated head package (IHP) of the reactor vessel to a body of the reactor vessel. The method comprises supporting a first stud tensioner device on a trolley, moving the trolley across a movement surface from a stored position to a deployment position adjacent the reactor vessel, engaging the first stud tensioner device with one or more of the closure studs, and operating the first stud tensioner device to tension/detension the one or more closure studs.

A bolt tensioning assembly includes a bolt having a through-hole extending longitudinally through the bolt. A ram is inserted into the through-hole. A top cap is configured to be attached to a first end portion of the bolt. A load distributing member is configured to engage the ram at a location adjacent a second end portion of the bolt to distribute a force exerted thereon by the ram, and an actuator is connected to the top cap to exert a force on the ram to cause the ram to engage the load distributing member such that the bolt is placed under tensile stress.

A screw tensioning device 2, 102 for tensioning or loosing tensionable screw connections comprises a fixation element 4, 104 to be connected to a screw 6, 106, a support element 8, 108 moveable relative to the fixation element 4, 104. The support element 8, 108 is arranged moveable relative to the fixation element 4, 104 to apply tension to or remove tension from the screw 6, 106. A piston 10, 110 is positioned and movable within the fixation element 4, 104. A volume 8, 108 containing a hydraulic fluid is defined at least partly by the piston 10, 110, the fixation element 4, 104 or the support element 8, 108. The movement of the piston 10, 110 manipulates the volume 8, 108 and thereby moves the fixation element 4, 104 with respect to the support element 8, 108.

A fully-functional automated bolt tensioning device capable of repeatedly tightening bolts within various locations of an operational wind turbine (e.g., hub, tower, etc.) to a specified tension range is provided. The device includes obstacle detection, alignment, an operational graphical user interface, and nut rotation data acquisition for reduced turbine preventative maintenance cost.

A bolt installation and removal (BIR) system is used for assembling and disassembling a nuclear vessel. The BIR system includes a platform with a stand for supporting the nuclear vessel. A track extends around an outside perimeter of the platform and multiple tool carts include wheels that roll on the track. Tool towers are located on the carts and include tool assemblies configured to install and remove bolts on the nuclear reactor vessel. Magazine towers also extend up from the tool carts next to the tool towers and include magazines that hold bolts for exchanging with the tool assemblies. Drive mechanisms move tool heads in the tool assemblies around a first vertical axis, vertically up and down, and laterally to more simply and reliably install and remove the bolts in a radioactive underwater environment.

A stand for hosting a Multiple Stud Tensioning Machine (MSTM) for tensioning working studs, the stand comprising a first assembly designed to lie on a floor, and a second assembly designed to receive the MSTM and movable in translation with respect to the first assembly thanks to a translation system.

A tensioning device for stretching a threaded bolt by applying tension to the threaded portion of the threaded bolt has a base and a support tube surrounding the threaded bolt and supported on the base. A cylinder housing is arranged as an axial extension on the support tube. A piston is moveably arranged in the cylinder housing and delimits together with an inner wall of the cylinder housing a hydraulic operating chamber. An interchangeable bush is rotatable relative to the piston and can be entrained axially by the piston. The interchangeable bush has an internal thread to establish a screw connection to the threaded portion. A device for path and/or position detection with first and second interacting elements is provided. The first element is fastened to the at least one piston and faces the cylinder housing. The second element is fastened to the cylinder housing and faces the piston.

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.

A system for preloading tension in a stud using an anti-seizure spacer for tapered thread connections is provided. The system comprises a hydraulic tensioning device including a nut configured for threadably engaging the stud, a foot, a cylinder having a first bore defined therein and a surface for engaging the foot, and a piston movably positioned within the first bore, wherein a hydraulic cavity is defined therebetween. The device further includes a puller screw including male tapered threads configured for being threadably coupled with female tapered threads on the stud. The puller screw includes a head configured for engaging a surface of the piston. The system also includes a spacer positioned between the male tapered threads of the puller screw and the female tapered threads of the stud. A method for preloading tension in a stud using the spacer is also provided.

A tensioning device for extending a threaded bolt by tensioning the threaded end section has a supporting tube surrounding the threaded end section, a cylinder arranged in continuation of the supporting tube and having at least one piston axially movable therein, an exchange socket which is screwable to the threaded end section and is configured such that it can be carried along axially by the piston, and a pin arranged in an axially movable manner in a longitudinal guide in the exchange socket. The pin end is axially supportable against that end of the threaded bolt that has the threaded end section. In order to assess the actually usable thread projection even in cases in which known tensioning devices provide imprecise results, the pin is formed in a radially widened manner at its pin end compared with the pin cross section.