Through-rotary centralizer

Abstract

Devices, systems, and methods are provided for a through-rotary centralizer for downhole operations. The through-rotary centralizer assists with centralizing a tool operating downhole, such as a bit. The through-rotary centralizer has a mandrel, a sleeve rotatably mounted around the mandrel, a floating hub slidably mounted around the sleeve, and centralizing arms mounted to the sleeve and floating hub. The centralizing arms extend to exert force against the inner wall of a tubular, such as wellbore casing, thereby providing stability to the downhole tool. Because the sleeve is rotatably mounted to the mandrel, the mandrel rotates within the sleeve and is able to transmit power or torque to the downhole tool, such as a bit. The centralizing arms are not required to rotate with the mandrel due to the rotatably mounted sleeve. A surface system may be used to control the position of the through-rotary centralizer.

1 . A through-rotary centralizer, comprising:
 a mandrel;   a sleeve rotatably mounted around a circumference of the mandrel;   a floating hub slidably mounted around a portion of the sleeve; and   one or more centralizing arms each having a first end and a second end, wherein the first end is attached to the floating hub and the second end is attached to the sleeve.   
     
     
         2 . The through-rotary centralizer of  claim 1 , wherein the floating hub is a first floating hub, the through-rotary centralizer further comprising:
 a second floating hub slidably mounted around the sleeve,   wherein the second end of the one or more centralizing arms is attached to the second floating hub.   
     
     
         3 . The through-rotary centralizer of  claim 1 , wherein the one or more centralizing arms is a bowspring. 
     
     
         4 . The through-rotary centralizer of  claim 1 , wherein the one or more centralizing arms is a bar linkage. 
     
     
         5 . The through-rotary centralizer of  claim 4 , wherein the bar linkage is a 3-bar linkage or a 4-bar linkage. 
     
     
         6 . (canceled) 
     
     
         7 . The through-rotary centralizer of  claim 1 , wherein the mandrel includes a longitudinal passage. 
     
     
         8 . The through-rotary centralizer of  claim 1 , further comprising:
 a coil spring mounted around the sleeve between the floating hub and an end stop of the sleeve.   
     
     
         9 . The through-rotary centralizer of  claim 2 , further comprising:
 a first coil spring and a second coil spring, wherein the first coil spring is mounted around the sleeve between the first floating hub and a first end stop of the sleeve and the second coil spring is mounted around the sleeve between the second floating hub and a second end stop of the sleeve.   
     
     
         10 . The through-rotary centralizer of  claim 1 , further comprising:
 a coil spring mounted around the sleeve between the floating hub and the second end of the one or more centralizing arms.   
     
     
         11 . The through-rotary centralizer of  claim 2 , further comprising:
 a coil spring mounted around the sleeve between the first floating hub and the second floating hub.   
     
     
         12 . The through-rotary centralizer of  claim 11 , further comprising:
 a second coil spring mounted around the sleeve between the first floating hub and the second floating hub.   
     
     
         13 . The through-rotary centralizer of  claim 1 , wherein the mandrel has a length greater than a length of the one or more centralizing arms. 
     
     
         14 . The through-rotary centralizer of  claim 1 , wherein the mandrel has a length greater than a length of the centralizing arm plus a length of the floating hub. 
     
     
         15 . The through-rotary centralizer of  claim 1 , wherein the sliding hub is slidably moved by hydraulic power. 
     
     
         16 . The through-rotary centralizer of  claim 1 , wherein sleeve rotates in only one direction around the mandrel. 
     
     
         17 . The through-rotary centralizer of  claim 1 , further comprising:
 a locking mechanism between the sleeve and mandrel that provides rotation of the sleeve around the mandrel in one direction and restricts rotation of the sleeve around the mandrel in the opposite direction.   
     
     
         18 . A through-rotary centralizer, comprising:
 a mandrel;   a sleeve rotatably mounted around the circumference of the mandrel; and   a cylinder non-rotatably mounted around the sleeve.   
     
     
         19 . The through-rotary centralizer of  claim 18 , wherein the cylinder has an outer diameter greater than the outer diameter of the mandrel. 
     
     
         20 . (canceled) 
     
     
         21 . A system for centralizing a tool string, comprising:
 a surface system comprising:
 a cable having a distal end; 
 a cable deployment system for extending and retrieving the cable; and 
 a non-transitory, computer-readable medium comprising instructions that, when executed by a processor, controls extension and retrieval of the cable by the cable deployment system; and 
   a tool string attached to the distal end of the cable, comprising:
 a through-rotary comprising:
 a mandrel; 
 a sleeve rotatably mounted around a circumference of the mandrel; 
 at least one floating hub slidably mounted around a portion of the sleeve; and 
 one or more centralizing arms each having a first end and a second end, wherein the first end is attached to the at least one floating hub and the second end is attached to the sleeve. 
 
   
     
     
         22 . (canceled) 
     
     
         23 . (canceled) 
     
     
         24 . The through-rotary centralizer of  claim 21 , wherein
 the at least one floating hub includes two floating hubs that slide along the sleeve,   the one or more centralizing arms include two centralizing arms attached at each end to the two floating hubs, and   the through-rotary centralizer further comprises coil springs around the sleeve that exert force against the two floating hubs.   
     
     
         25 . (canceled) 
     
     
         26 . (canceled)