05722820 is referenced by 27 patents and cites 10 patents.

A progressing cavity pump is provided in which the compressive fit between the rotor and stator is gradually reduced with the distance from the suction end of the pump. This gradual decrease in compressive fit allows for increased slippage near the discharge end of the pump, resulting in better distribution of the internal differential pressure along the length of the pump. The differential pressure distribution in turn reduces heat build-up near the discharge end, increasing the life of the elastomeric stator or rotor.

Title
Progressing cavity pump having less compressive fit near the discharge
Application Number
8/654359
Publication Number
5722820
Application Date
May 28, 1996
Publication Date
March 3, 1998
Inventor
Kamran Z Mirza
Springfield
OH, US
Alan G Wild
Woodstock
OH, US
Agent
Thompson Hine & Flory
Assignee
Robbins & Myers
OH, US
IPC
F04C 5/00
F04C 2/107
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