Threaded Connection Having Different Upper and Lower Threads for Submersible Well Pump Modules

摘要

An electrical submersible pump assembly has pump, motor and pressure equalizer modules. A first adapter, which secures to the first module, has an external set of first adapter threads. A second adapter, which secures to the second module, has an external set of second adapter threads. A collar has an internal set of collar first threads that engage the first adapter threads, and an internal set of collar second threads that engage the second adapter threads. The collar first and second threads differ from each other, such that rotation of the collar relative to the first and second modules pulls the first and second modules toward each other. The pitches of the collar first and second threads may differ. Or, the collar first and second threads may turn in opposite directions.

主权项

1. A submersible pump assembly, comprising:
a plurality of modules including a pump, a motor, and a pressure equalizer for reducing a pressure differential between lubricant in the motor and hydrostatic pressure of well fluid; a first one of the modules having a first drive shaft rotatably mounted therein, the first drive shaft extending along a longitudinal axis and having a splined end; a second one of the modules having a second drive shaft rotatably mounted therein, the second drive shaft having a splined end; a first adapter secured to the first one of the modules, the first adapter having a set of first adapter threads; a second adapter secured to the second one of the modules, the second adapter having a set of second adapter threads; a collar having a set of collar first threads that engage the first adapter threads, and a set of collar second threads that engage the second adapter threads; wherein the collar first and second threads differ from each other, such that rotation of the collar relative to the first and second modules in a single direction pulls the first and second modules toward each other and positions the splined ends of first and second drive shafts in full engagement with each other.