摘要 |
Disclosed herein is a short stud tensioning apparatus for tensioning and detensioning an externally threaded stud or bolt protruding a short distance above a surface. The apparatus includes an internally threaded sleeve and a gripper having internal and external threads. The gripper surrounds the stud for threadably engaging the stud and the sleeve surrounds the gripper for threadably engaging the gripper. When engaged on the stud, the gripper serves as an extension of the stud. Hydraulic force is applied to a puller bar which is threadably connected to the gripper so that the gripper travels upwardly when hydraulic force is applied to the puller bar. The upwardly travel of the puller bar causes a correspondingly upward translation of the stud thus tensioning the stud. While the stud is in tension, the sleeve is run down the gripper until the sleeve engages the surface from which the stud protrudes. The stud will thus remain in tension even after the hydraulic force acting on the puller bar is removed. After the tensioning operation is completed, only the sleeve and gripper remain about the stud. Hence, the sleeve and gripper combination replaces the traditional nut. Of course, the stud may be detensioned in a manner similar to its tensioning except that the sleeve is disengaged from the surface by running the sleeve and gripper up the stud.
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