Patent ID: 9657556
Date: 2017-05-23
CPC Classifications: E21B,F04C,F04D

Claim:
1. A well pump assembly for pumping well fluid from a well, comprising: a pump; an electrical motor operatively coupled to the pump for driving the pump; a seal section operatively coupled to the motor for reducing a pressure difference between a dielectric lubricant in the motor and a hydrostatic well fluid pressure on an exterior of the motor, the seal section comprising: a housing having a longitudinal axis and a cylindrical inner surface; first and second end members at opposite ends of the housing; a guide tube concentric with the axis and fixed between the end members; an outer bellows within the housing surrounding the guide tube, the outer bellows having a fixed end secured to the first end member and a floating end that moves axially relative to the fixed end, and the outer bellows having a flexible corrugated wall that is closely spaced to the inner surface of the housing and moves axially relative to the housing when the outer bellows contracts and extends; a sleeve within the outer bellows, the sleeve having an external flange secured to the floating end of the outer bellows and an internal flange located within the outer bellows; an inner bellows surrounding the guide tube, the inner bellows having a fixed end secured to the second end member and a floating end located within the outer bellows and secured to the internal flange; a guide ring secured to the wall of the outer bellows between the fixed and floating ends of the outer bellows, the guide ring having a contacting surface protruding slightly from the wall and slidingly engaging the inner surface of the housing as the outer bellows contracts and extends; and wherein the guide ring has an inner diameter that is larger than an outer diameter of the sleeve.