Progressing cavity devices and assemblies for coupling multiple stages of progressing cavity devices

Abstract

A progressing cavity device includes a stator including a first end, a second end, and an inner surface formed from a metallic material that extends between the first end and the second end, and a rotor rotatably disposed in the stator, the stator including a first end, a second end, and an outer surface formed from a metallic material that extends between the first end and the second end, wherein the outer surface of the rotor contacts the inner surface of the stator, wherein the inner surface of the stator includes a conical taper extending between the first end and the second end, wherein the outer surface of the rotor includes a conical taper extending between the first end and the second end.

What is claimed is: 
     
         1 . A downhole assembly, comprising:
 a first shaft;   a second shaft; and   a drive connector coupled between the first shaft and the second shaft, wherein the drive connector is configured to permit an axial offset between the first shaft and the second shaft such that a central axis of the first shaft is radially offset from a central axis of the second shaft, and wherein the drive connector is configured to transfer torque between the first shaft and the second shaft.   
     
     
         2 . The downhole assembly of  claim 1 , wherein the drive connector is configured to permit the first shaft to pivot relative to the second shaft about a first axis extending orthogonal to the central axis of the first shaft. 
     
     
         3 . The downhole assembly of  claim 2 , wherein the drive connector is configured to permit the first shaft to pivot relative to the second shaft about a second axis extending orthogonal to the central axis of the first shaft, and wherein the second axis is disposed at a non-zero angle from the first shaft. 
     
     
         4 . The downhole assembly of  claim 1 , wherein the drive connector is configured to permit the first shaft to pivot relative to the second shaft about the central axis of the first shaft. 
     
     
         5 . The downhole assembly of  claim 1 , wherein the first shaft comprises a rotor of a progressing cavity pump or power section and the second shaft comprises a drive shaft of a slidable connector module. 
     
     
         6 . The downhole assembly of  claim 5 , further comprising a thrust module comprising:
 a bearing shaft coupled to the drive shaft of the slidable connector module via an axially slidable connection configured to permit relative axial movement between the bearing shaft and the drive shaft, and wherein the axially slidable connection is configured to permit transmission of torque between the bearing shaft and the drive shaft; and   a thrust bearing disposed radially between the bearing shaft and an outer housing of the thrust module.   
     
     
         7 . The downhole assembly of  claim 6 , wherein an end of the bearing shaft of the thrust module comprises a plurality of circumferentially spaced splines that are insertable into a plurality of circumferentially spaced grooves formed in an end of the drive shaft of the slidable connector module. 
     
     
         8 . The downhole assembly of  claim 1 , wherein:
 the first shaft comprises a first key;   the second shaft comprises a second key;   the drive connector comprises a body, a first groove formed in the body, and a second groove formed in the body; and   the first key is slidably disposed in the first groove and the second key is slidably disposed in the second groove.   
     
     
         9 . A downhole assembly, comprising:
 a first shaft;   a second shaft; and   a drive connector coupled between the first shaft and the second shaft for transferring torque between the first shaft and the second shaft, the drive connector defining both a first slidable connection between the drive connector and the first shaft permitting the drive connector to slide laterally relative to the first shaft along a first axis, and a second slidable connection between the drive connector and the second shaft permitting the drive connector to slide laterally relative to the second shaft along a second axis.   
     
     
         10 . The downhole assembly of  claim 9 , wherein the second axis extends orthogonally relative to the first axis. 
     
     
         11 . The downhole assembly of  claim 9 , wherein relative movement between the first shaft and the drive connector along a longitudinal axis of the first shaft is restricted. 
     
     
         12 . The downhole assembly of  claim 9 , wherein the first slidable connection comprises a first groove and a first key slidably received in the first groove, and the second slidable connection comprises a second groove and a second key slidably received in the second groove. 
     
     
         13 . The downhole assembly of  claim 9 , wherein the drive connector is configured to permit the first shaft to pivot relative to the second shaft about a pivot axis extending orthogonal to a longitudinal axis of the first shaft. 
     
     
         14 . A downhole assembly, comprising:
 a first shaft;   a second shaft; and   a drive connector coupled between the first shaft and the second shaft for transferring torque between the first shaft and the second shaft;   wherein a first slidable connection is formed between first shaft and the drive connector, the first slidable connection defined by a first groove and a first key slidably received in the first groove;   wherein a second slidable connection is formed between second shaft and the drive connector, the second slidable connection defined by a second groove and a second key slidably received in the second groove.   
     
     
         15 . The downhole assembly of  claim 14 , wherein the first groove is formed in the first shaft and the drive connector comprises the first key. 
     
     
         16 . The downhole assembly of  claim 14 , wherein the first groove is formed in the drive connector and the first shaft comprises the first key. 
     
     
         17 . The downhole assembly of  claim 14 , wherein the first key extends laterally along a first axis and the second key extends laterally along a second axis. 
     
     
         18 . The downhole assembly of  claim 17 , wherein the first axis extends orthogonally relative to the second axis. 
     
     
         19 . The downhole assembly of  claim 14 , wherein relative movement between the first groove and the first key along a longitudinal axis of the first shaft is restricted. 
     
     
         20 . The downhole assembly of  claim 14 , wherein the drive connector is configured to permit the first shaft to pivot relative to the second shaft about a first axis extending orthogonal to a longitudinal axis of the first shaft.