Abstract: A well pump assembly includes a pump and a motor that contains a dielectric motor lubricant and a pressure equalizer containing a bellows. The bellows has an interior in fluid communication with the motor lubricant and an exterior immersed in well fluid. The bellows is axially extendable and contractible in response to a pressure differential between the well fluid and the motor lubricant. A tube has a lower end secured to a tube port in the pressure equalizer housing and an upper end secured to a lower end of the bellows. The tube has a center line that makes at least one curved flexible bend between the tube upper end and the tube lower end to enable the tube to flex as the bellows extends and contracts.

Abstract: A well pump assembly includes a pump and a motor that contains a dielectric motor lubricant and a pressure equalizer containing a bellows. The bellows has an interior in fluid communication with the motor lubricant and an exterior immersed in well fluid. The bellows is axially extendable and contractible in response to a pressure differential between the well fluid and the motor lubricant. A tube has a lower end secured to a tube port in the pressure equalizer housing and an upper end secured to a lower end of the bellows. The tube has a center line that makes at least one curved flexible bend between the tube upper end and the tube lower end to enable the tube to flex as the bellows extends and contracts.

Abstract: A submersible pump assembly has modules, including a rotary pump, an electrical motor, and a seal section located between the motor and the pump. The seal section has a tubular housing with a lower adapter secured to the housing and joining the seal section with the motor. An upper adapter is secured to the housing and joins the seal section with another one of the modules. An inlet port in the upper adapter admits well fluid into the housing. A tubular, flexible compensator element has an upper end sealed to the upper adapter and a lower end sealed to the lower adapter. A communication passage in the lower adapter admits lubricant from the motor into the compensator element. A cap is mounted around the upper end of the compensator element. The cap has a skirt extending radially outward to limit upward expansion of the compensator element.

Abstract: A submersible well pump assembly has a rotary pump, a motor, and a seal section coupled between the motor and the pump. The seal section has a cylindrical housing having upper and lower adapter and a shaft extending axially through the housing. A guide tube surrounds the shaft and a bellows surrounds the guide tube. A well fluid passage communicates well fluid to a well fluid chamber between the bellows and the housing. A guide tube passage extends axially within the guide tube between an interior and an exterior of the guide tube from an upper portion to a lower portion of the guide tube for communicating lubricant in the motor with lubricant within the bellows.

Abstract: A submersible pump assembly has modules, including a rotary pump, an electrical motor, and a seal section located between the motor and the pump. The seal section has a tubular housing with a lower adapter secured to the housing and joining the seal section with the motor. An upper adapter is secured to the housing and joins the seal section with another one of the modules. An inlet port in the upper adapter admits well fluid into the housing. A tubular, flexible compensator element has an upper end sealed to the upper adapter and a lower end sealed to the lower adapter. A communication passage in the lower adapter admits lubricant from the motor into the compensator element. A cap is mounted around the upper end of the compensator element. The cap has a skirt extending radially outward to limit upward expansion of the compensator element.

Abstract: A labyrinth type seal section for use with an electrical submersible pump assembly having a guide tube with an axial bore to port wellbore fluid to a lower end of the seal section. Lubricating fluid fills substantially all of the seal section above an interface between the lubricating fluid and the wellbore fluid. The guide tube circumscribes a drive shaft that extends between a motor and a pump. The guide tube and shaft form an annulus filled with lubricating fluid that communicates to the well fluid and to the motor, so that pressure in the motor can be equalized to pressure of the ambient well fluid.

Abstract: A labyrinth type seal section for use with an electrical submersible pump assembly having a guide tube with an axial bore to port wellbore fluid to a lower end of the seal section. Lubricating fluid fills substantially all of the seal section above an interface between the lubricating fluid and the wellbore fluid. The guide tube circumscribes a drive shaft that extends between a motor and a pump. The guide tube and shaft form an annulus filled with lubricating fluid that communicates to the well fluid and to the motor, so that pressure in the motor can be equalized to pressure of the ambient well fluid.

Abstract: A submersible well pump assembly has a rotary pump, a motor, and a seal section coupled between the motor and the pump. The seal section has a cylindrical housing having upper and lower adapter and a shaft extending axially through the housing. A guide tube surrounds the shaft and a bellows surrounds the guide tube. A well fluid passage communicates well fluid to a well fluid chamber between the bellows and the housing. A guide tube passage extends axially within the guide tube between an interior and an exterior of the guide tube from an upper portion to a lower portion of the guide tube for communicating lubricant in the motor with lubricant within the bellows.