Portable Downforce System and Method

Abstract

A wellbore tubular handling system for applying a downforce to wellbore tubulars using a service rig. A downforce system includes a first frame assembly coupled to a slip assembly for engaging wellbore tubulars, a base member connected to the first frame assembly, and an actuator adapted to extend and/or retract the first frame assembly between a first position and a second position, wherein the second position is laterally displaced from the first position along a path formed by extension of the actuator, and wherein the base member is connected to the mast of the service rig. A method of applying a downforce to a wellbore tubular using a downforce system for a service rig.

1 . A method for moving wellbore tubulars into or out of a wellhead, the method comprising,
 positioning a travelling slip assembly in line with a center of the wellhead,   feeding a tubular through the travelling slip assembly;   applying a downforce or an upforce using the travelling slip assembly to push the tubular into or pull the tubular out of the wellhead; and   retracting the travelling slip assembly so that it is no long in line with the center of the wellhead when not in use.   
     
     
         2 . The method of  claim 1  wherein the positioning or the retracting or both comprise lateral movement of the travelling slip assembly. 
     
     
         3 . The method of  claim 1  wherein the positioning or the retracting or both consist of lateral movement of the travelling slip assembly. 
     
     
         4 . The method of  claim 1  further comprising installing a portable downforce system comprising the travelling slip assembly to a mast of a service rig before positioning the tubular in line with the center of the wellhead. 
     
     
         5 . The method of  claim 4  further comprising uninstalling the portable downforce system when not in use. 
     
     
         6 . The method of  claim 1  wherein the wellhead is associated with a wellbore having a wellbore trajectory, having a string of wellbore tubulars therein, wherein a resistance force resisting movement of the string of wellbore tubulars is substantially equal to or exceeds the force of gravity urging movement of the string of tubulars into the wellbore. 
     
     
         7 . The method of  claim 6  wherein the wellbore trajectory comprises a shallow horizontal well, having a relatively shorter substantially vertical section and a relatively longer horizontal or deviated section. 
     
     
         8 . The method of  claim 1  wherein the wellhead is associated with a steam assisted gravity drainage (SAGD) well. 
     
     
         9 . The method of  claim 1  wherein a pressure at the wellhead has been substantially equalized by a kill fluid such that the pressure is substantially reduced to or is substantially zero.