Longitudinal Positioning Tool for a Rod String

Abstract

A positioning tool longitudinally positions a rod string relative to a tubing string while the rod string remains by a drive head. An upper hollow shaft member of the tool is fixed to the rod string by a rod clamp while a lower hollow shaft member is slidably coupled to the upper hollow shaft member such that the upper and lower hollow shaft members are rotatable together and longitudinally adjustable relative to one another. The bottom end of the lower hollow shaft member is arranged to be coupled to the rotatable output of the drive head. A hydraulic lifting assembly is coupled between the upper and lower shaft members to hydraulically control the longitudinal position of the rod string and upper shaft member relative to the tubing string and the lower shaft member.

1 . A positioning tool for longitudinally positioning a rod string supported to rotate within a tubing string by a drive head with a rotatable output supported above the tubing string, the tool comprising:
 a rod clamp arranged to be clamped about the rod string at a location spaced above the drive head;   an upper hollow shaft member arranged to be fixed to the rod clamp so as to be arranged to receive the rod string therethrough and be arranged to rotate with the rod string;   a lower hollow shaft member slidably coupled to the upper hollow shaft member such that the upper and lower hollow shaft members are rotatable together with one another and are longitudinally adjustable relative to one another, the lower hollow shaft member having a bottom end arranged to be coupled to the rotatable output of the drive head;   a hydraulic lifting assembly comprising:
 a lower portion arranged to be supported above the tubing string; 
 an upper portion arranged to support the upper hollow shaft member and rod clamp thereon; 
 the upper portion being coupled to the lower portion so as to be longitudinally movable relative to the lower portion between a retracted position in which the rod clamp is supported thereon at a first elevation relative to the tubing string and an extended position in which the upper portion is raised upwardly relative to the retracted position and the rod clamp is supported thereon at a second elevation relative to the tubing string which is greater than the first elevation; and 
 a hydraulic actuator arranged to operate the upper portion between the retracted position and the extended position; and 
   at least one bearing member supporting the upper hollow shaft member for rotation relative to the tubing string.   
     
     
         2 . The tool according to  claim 1  wherein the upper and lower portions of the hydraulic lifting assembly comprise tubular casings which are telescopically connected. 
     
     
         3 . The tool according to  claim 1  wherein one of the upper portion and the lower portion comprises a hydraulic chamber and the other one of the upper portion and the lower portion comprises a piston received within the hydraulic chamber, the hydraulic actuator being coupled to the hydraulic chamber and being arranged to control a volume of hydraulic fluid in the hydraulic chamber for operating the upper portion between the retracted position and the extended position. 
     
     
         4 . The tool according to  claim 1  wherein the lower portion of the hydraulic lifting assembly is arranged to be supported on the drive head. 
     
     
         5 . The tool according to  claim 1  wherein said at least one bearing member includes a bearing assembly supporting the upper hollow shaft member rotatably on the upper portion of the hydraulic lifting assembly and wherein the lower portion of the hydraulic lifting assembly is arranged to be supported on the drive head in fixed relation to the tubing string. 
     
     
         6 . The tool according to  claim 1  wherein said at least one bearing member includes a bearing assembly supported between the lower portion of the hydraulic lifting assembly and the lower hollow shaft member such that the lower hollow shaft member is rotatably and radially supported relative to the lower portion of the hydraulic lifting assembly. 
     
     
         7 . The tool according to  claim 1  further comprising a spline connection slidably coupling the upper hollow shaft member to the lower hollow shaft member. 
     
     
         8 . A rod driving tool for longitudinally positioning and driving rotation of a rod string relative to a tubing string receiving the rod string therein, the tool comprising:
 a drive head including housing supported above the tubing string and a rotatable output arranged to receive the rod string concentrically therethrough;   a rod clamp arranged to be clamped about the rod string at a location spaced above the drive head;   an upper hollow shaft member arranged to be fixed to the rod clamp so as to be arranged to receive the rod string therethrough and be arranged rotate with the rod string;   a lower hollow shaft member slidably coupled to the upper hollow shaft member such that the upper and lower hollow shaft members are rotatable together with one another and are longitudinally adjustable relative to one another;   the lower hollow shaft member being coupled to the rotatable output of the drive head for rotation therewith relative to the housing of the drive head;   a hydraulic lifting assembly comprising:
 a lower portion supported on the housing of the drive head; 
 an upper portion supporting the upper hollow shaft member and rod clamp thereon; 
 the upper portion being coupled to the lower portion so as to be longitudinally movable relative to the lower portion between a retracted position in which the rod clamp is supported thereon at a first elevation relative to the tubing string and an extended position in which the upper portion is raised upwardly relative to the retracted position and the rod clamp is supported thereon at a second elevation relative to the tubing string which is greater than the first elevation; and 
 a hydraulic actuator arranged to operate the upper portion between the retracted position and the extended position; and 
   at least one bearing member supporting the upper hollow shaft member for rotation relative to the housing of the drive head.   
     
     
         9 . The tool according to  claim 8  wherein the upper and lower portions of the hydraulic lifting assembly comprise tubular casings which are telescopically connected. 
     
     
         10 . The tool according to  claim 8  wherein one of the upper portion and the lower portion comprises a hydraulic chamber and the other one of the upper portion and the lower portion comprises a piston received within the hydraulic chamber, the hydraulic actuator being coupled to the hydraulic chamber and being arranged to control a volume of hydraulic fluid in the hydraulic chamber for operating the upper portion between the retracted position and the extended position. 
     
     
         11 . The tool according to  claim 8  further comprising a spline connection slidably coupling the upper hollow shaft member to the lower hollow shaft member.