Eccentric Adjustment Coupling For Mud Motors

Abstract

According to one aspect, there is provided a drilling motor assembly having a power section configured to generate torque, a transmission section coupled to the power section, and a bearing section coupled to the transmission section, the bearing section configured to couple to a drill bit. The transmission section includes a housing assembly having a bore formed therethrough, the housing assembly having a central axis defined therethrough and the bore having a central axis defined therethrough, in which the central axis of the bore is radially offset from the central axis of the housing assembly.

What is claimed is: 
     
         1 . A drilling motor assembly, comprising:
 a power section configured to generate torque;   a transmission section coupled to the power section, comprising:
 a housing assembly comprising a bore formed therethrough, the housing assembly having a central axis defined therethrough and the bore having a central axis defined therethrough, 
 wherein the central axis of the bore is radially offset from the central axis of the housing assembly; and 
   a bearing section coupled to the transmission section, the bearing section configured to couple to a drill bit.   
     
     
         2 . The assembly of  claim 1 , wherein the transmission section comprises a transmission shaft disposed within the bore of the housing assembly. 
     
     
         3 . The assembly of  claim 2 , wherein the radial offset between the central axis of the bore and the central axis of the housing assembly provides clearance between the transmission shaft and an internal surface of the housing assembly. 
     
     
         4 . The assembly of  claim 1 , wherein the radial offset between the central axis of the bore and the central axis of the housing assembly is up to 5 mm. 
     
     
         5 . The assembly of  claim 1 , wherein a cross-section of the housing assembly comprises a variable wall thickness. 
     
     
         6 . (canceled) 
     
     
         7 . The assembly of  claim 2 , wherein a ratio between the diameter of the transmission shaft and the diameter of the bore formed through the housing assembly is 1:1.314. 
     
     
         8 . (canceled) 
     
     
         9 . (canceled) 
     
     
         10 . A drilling motor assembly, comprising:
 a power section configured to generate torque;   a transmission section coupled to the power section, comprising:
 an adjustable housing assembly comprising a first sub coupled to a second sub and a bore formed therethrough, the first sub having a first central axis defined therethrough, the second sub having a second central axis defined therethrough, 
 wherein the bore formed through the adjustable housing assembly comprises a first bore and a second bore, wherein the first bore is formed through the first sub and the second bore is formed through the second sub, the first bore having a first central axis defined therethrough and the second bore having a second central axis defined therethrough, 
 wherein the first central axis of the first sub is radially offset from the first central axis of the first bore, and wherein the second central axis of the second sub is radially offset from the second central axis of the second bore; and 
   a bearing section coupled to the transmission section, the bearing section configured to couple to a drill bit.   
     
     
         11 . The assembly of  claim 10 , wherein the adjustable housing assembly is configured to adjustably bend such that an offset angle is formed between the first central axis of the first sub and the second central axis of the second sub. 
     
     
         12 . The assembly of  claim 10 , wherein the adjustable housing assembly is configured to adjustably bend such that an offset angle of up to  3  degrees is formed between the first central axis of the first sub and the second central axis of the second sub. 
     
     
         13 . The assembly of  claim 10 , wherein the transmission section comprises a transmission shaft disposed within the bore of the adjustable housing assembly. 
     
     
         14 . (canceled) 
     
     
         15 . The assembly of  claim 13 , wherein the radial offset between the central axis of the bore and the central axis of the adjustable housing assembly provides clearance between the transmission shaft and an internal surface of the adjustable housing assembly when the adjustable housing assembly is bent such that an offset angle is formed between the first central axis of the first sub and the second central axis of the second sub. 
     
     
         16 . (canceled) 
     
     
         17 . The assembly of  claim 13 , wherein a ratio between the the diameter of the transmission shaft and outer diameter of the adjustable housing assembly is 1:2.313. 
     
     
         18 . The assembly of  claim 13 , wherein a ratio between the diameter of the transmission shaft and the diameter of the bore formed through the adjustable housing assembly is 1:1.314. 
     
     
         19 . (canceled) 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . (canceled) 
     
     
         23 . (canceled) 
     
     
         24 . (canceled) 
     
     
         25 . (canceled) 
     
     
         26 . (canceled) 
     
     
         27 . (canceled) 
     
     
         28 . (canceled) 
     
     
         29 . A method of using a drilling motor assembly, the method comprising:
 disposing the drilling motor assembly having a power section, a transmission section, and a bearing section downhole; and   transmitting torque from the power section to the bearing section through the transmission section,   wherein the transmission section comprises an adjustable housing assembly having a central axis defined therethrough and a bore formed therethrough, the bore having a central axis defined therethrough,   wherein the central axis of the bore is radially offset from the central axis of the adjustable housing assembly.   
     
     
         30 . The method of  claim 29 , wherein the transmission section comprises a transmission shaft disposed within the bore of the housing assembly. 
     
     
         31 . The method of  claim 30 , wherein the radial offset between the central axis of the bore and the central axis of the housing assembly provides clearance between the transmission shaft and an internal surface of the housing assembly. 
     
     
         32 . (canceled) 
     
     
         33 . The method of  claim 30 , wherein a ratio between the diameter of the transmission shaft and the outer diameter of the adjustable housing assembly is 1:2.313. 
     
     
         34 . The method of  claim 30 , wherein a ratio between the diameter of the transmission shaft and the diameter of the bore formed through the adjustable housing assembly is 1:1.314. 
     
     
         35 . The method of  claim 29 , wherein the adjustable housing assembly comprises a first sub coupled to a second sub and a bore formed therethrough, the first sub having a first central axis defined therethrough and the second sub having a second central axis defined therethrough. 
     
     
         36 . The method of  claim 35 , wherein the adjustable housing assembly is configured to adjustably bend such that an offset angle of up to 3 degrees is formed between the first central axis of the first sub and the second central axis of the second sub.