Threaded Connection with Engaging Lugs for Electrical Submersible Pump

Abstract

An electrical submersible pump assembly has modules including a pump, a motor, and a seal section. A threaded connection between at least two of the modules has a first adapter and a second adapter. A collar rotatably carried and axially movable on one of the adapters is in threaded engagement with threads of the other adapter when the threaded connection is made up. First adapter lugs are spaced circumferentially apart from each other around the first adapter. Second adapter slots are spaced circumferentially apart from each other around the second adapter. The lugs slide into the slots while the adapters are brought together. Each of the lugs and each of the slots have side edges that are parallel with the axis. The side edges of the lugs abut the side edges of the slots to prevent rotation of the first and second adapters relative to each other.

1 . An electrical submersible pump assembly, comprising:
 a plurality of modules including a pump, a motor, and a seal section for reducing a pressure differential between lubricant in the motor and hydrostatic pressure of well fluid;   a threaded connection between at least two of the modules, comprising:   a first adapter and a second adapter, the first and second adapters having a longitudinal axis;   a collar rotatably carried and axially movable on one of the adapters, the collar being in threaded engagement with threads of the other adapter when the threaded connection is made up;   first adapter lugs spaced circumferentially apart from each other around the first adapter;   second adapter slots spaced circumferentially apart from each other around the second adapter; wherein   the lugs slide into the slots while the adapters are brought together; and   each of the lugs and each of the slots have side edges that are parallel with the axis, the side edges of the lugs abutting the side edges of the slots to prevent rotation of the first and second adapters relative to each other.   
     
     
         2 . The assembly according to  claim 1 , further comprising:
 a plurality of first adapter electrical terminals mounted in the first adapter and spaced circumferentially about the axis at a lesser radial distance from the axis than the lugs;   a plurality of second adapter electrical terminals in the second adapter and spaced circumferentially about the axis at a lesser radial distance from the axis than the slots, for engagement by the first adapter electrical connectors.   
     
     
         3 . The assembly according to  claim 2 , further comprising:
 at least one inclined cam surface on each the lugs extending between opposite sides edges of each of the lugs; and wherein   the cam surfaces engage the side edges of the slots as the first and second adapters are brought together to incrementally rotate one of the adapters relative to the other until the electrical terminals of the first adapter and the second adapter are axially aligned.   
     
     
         4 . The assembly according to  claim 2 , further comprising:
 a pair of inclined cam surfaces on each the lugs extending between opposite sides edges of each of the lugs toward each other; wherein   the lugs protrude axially past the electrical terminals in the first adapter; and   the engagement of the cam surfaces of the lugs with the side edges of the slots causes the first and second adapters to incrementally rotate relative to each other until the electrical terminals of the first adapter and the second adapter are axially aligned.   
     
     
         5 . The assembly according to  claim 1 , further comprising:
 a first drive shaft in one of the modules, the first drive shaft having a splined end;   a second drive shaft in an adjoining one of the modules, the second drive shaft having a splined end,   a sleeve coupling having a cylindrical body with an inner wall and an outer wall and internal splines separated by spline grooves in the inner wall that slide over and engage the splined end of the second drive shaft, the sleeve having a rim on a first end; and   teeth formed on the rim of the coupling, each of the teeth extending from the inner wall to the outer wall and being aligned with one of the spline grooves for incrementally rotating the shafts relative toe ach other and guiding the splined end of the first drive shaft into engagement with the internal splines.   
     
     
         6 . The assembly according to  claim 1 , wherein:
 the first adapter has a cylindrical inner wall and a cylindrical outer wall that are concentric with each other;   circumferentially extending recesses are located in the outer wall of the first adapter between adjacent one of the lugs; and   each of the recesses has a radial depth that is less than a radial thickness of the first adapter measured the inner and the outer walls of the first adapter.   
     
     
         7 . The assembly according to  claim 1 , wherein:
 the first adapter has a cylindrical inner wall and a cylindrical outer wall that are concentric with each other;   circumferentially extending recesses are located in the outer wall of the first adapter between adjacent one of the lugs; and   each of the recesses has a radially outward facing back wall.   
     
     
         8 . The assembly according to  claim 1 , wherein:
 each of the lugs has an inner side and an outer side that are cylindrical segments.   
     
     
         9 . The assembly according to  claim 1 , wherein:
 each of the lugs has an end that is located in a plane perpendicular to the axis.   
     
     
         10 . The assembly according to  claim 1 , wherein:
 each of the lugs has on an end two cam surfaces that incline from opposite side edges of each of the lugs to a crest; and   each of the slots has a slot base having two inclined surfaces that incline from opposite sides edges of each of the slots to a valley, defining a mating contour for receiving one of the lugs.   
     
     
         11 . An electrical submersible pump assembly, comprising:
 a plurality of modules including a pump, a motor, and a seal section for reducing a pressure differential between lubricant in the motor and hydrostatic pressure of well fluid;   a threaded connection between at least two of the modules, comprising:   a first adapter having an axis;   a second adapter;   a collar rotatably carried and axially movable on one of the adapters, the collar being in threaded engagement with threads of the other adapter when the threaded connection is made up;   a male portion extending from one of the adapters, the male portion having cylindrical, concentric inner and outer walls;   a receptacle portion in the other adapter, the receptacle portion having cylindrical concentric inner and outer walls;   male portion lugs formed in the outer wall of the male portion, the male portion lugs being spaced circumferentially apart from each other by male portion slots, each of the male portion slots having a back wall that faces radially outward;   receptacle portion lugs formed in the inner wall of the receptacle portion, each of the receptacle portion lugs being spaced circumferentially apart from each by receptacle portion slots, each of the receptacle portion slots having a back wall that faces radially inward; wherein   the male portion lugs slide into the receptacle portion slots and the receptacle portion lugs slide into the male portion slots while the adapters are brought together; and   each of the male portion lugs and each of the receptacle portion lugs have side edges that are parallel with the axis, the side edges of the male portion lugs sliding along the side edges of the receptacle portion slots as the male portion lugs slide into the receptacle portion slots, to prevent rotation of the first and second adapters relative to each other.   
     
     
         12 . The assembly according to  claim 11 , wherein the outer wall of the male portion is in contact with the back walls of the receptacle portion slots when the connection is made up. 
     
     
         13 . The assembly according to  claim 11 , wherein:
 each of the male portion slots has a radial depth less than a radial thickness of the male portion measured between the inner and outer walls of the male portion at the male portion lugs.   
     
     
         14 . The assembly according to  claim 11 , wherein:
 each of the receptacle portion slots has a radial depth less than a radial thickness of the receptacle portion measured between the inner and outer walls of the receptacle portion at the receptacle portion lugs.   
     
     
         15 . The assembly according to  claim 11 , wherein:
 each of the male portion slots has a shoulder extending between the side edges of each of the male portion slots; and   each of the receptacle portion lugs has an end that abuts one of the shoulders when the connection is made up.   
     
     
         16 . An electrical submersible pump assembly, comprising:
 a plurality of modules including a pump, a motor, and a seal section for reducing a pressure differential between lubricant in the motor and hydrostatic pressure of well fluid;   a threaded connection between at least two of the modules, comprising:   a first adapter having an axis;   a second adapter;   a collar rotatably carried and axially movable on one of the adapters, the collar being in threaded engagement with threads of the other adapter when the threaded connection is made up;   first adapter lugs spaced circumferentially apart from each other around the first adapter;   second adapter lugs spaced circumferentially apart from each other around the second adapter that slide between the first adapter lugs while the first and second adapters are brought together;   each of the first adapter lugs and the second adapter lugs having side edges that are parallel with the axis, the side edges of the first adapter lugs abutting the side edges of the second adapter lugs to prevent rotation of the first and second adapters relative to each other;   a plurality of first adapter electrical terminals mounted in the first adapter and spaced circumferentially about the axis at a lesser radial distance from the axis than the first adapter lugs;   a plurality of second adapter electrical terminals in the second adapter and spaced circumferentially about the axis at a lesser radial distance from the axis than the second adapter lugs, for engagement by the second adapter electrical connectors;   at least one inclined cam surface on an end of each of the first adapter lugs extending between opposite sides edges of each of the first adapter lugs;   at least one inclined cam surface on an end of each of the second adapter lugs extending between opposite side edges of each of the second adapter lugs; and wherein   the cam surfaces of the first adapter lugs engage the cam surfaces of the second adapter lugs as the first and second adapters are brought together to incrementally rotate one of the adapters relative to the other until the electrical terminals of the first adapter and the second adapter are axially aligned.   
     
     
         17 . The assembly according to  claim 16 , wherein:
 the cam surfaces on each of the lugs intersect each other at a crest equidistant between the side edges of each of the lugs.   
     
     
         18 . The assembly according to  claim 16 , wherein:
 the first adapter lugs protrude axially past the electrical terminals in the first adapter; and   the second adapter lugs protrude axially past the electrical terminals in the second adapter.   
     
     
         19 . The assembly according to  claim 16 , further comprising:
 a first drive shaft in one of the modules, the first drive shaft having a splined end;   a second drive shaft in an adjoining one of the modules, the second drive shaft having a splined end,   a sleeve coupling having a cylindrical body with an inner wall and an outer wall and internal splines separated by spline grooves in the inner wall that slide over and engage the splined end of the second drive shaft, the sleeve having a rim on a first end; and   teeth formed on the rim of the coupling, each of the teeth extending from the inner wall to the outer wall and being aligned with one of the spline grooves for incrementally rotating the shafts relative to each other and guiding the spliend end of the first drive shaft into engagement with the internal splines.   
     
     
         20 . The assembly according to  claim 16 , wherein:
 the second adapter lugs define slots between them; and   each of the slots has a base with a contour mating with the cam surface on each of the first adapter lugs.