Home default The simplest type of fixed-displacement pump is the gear pump, in which the hydraulic fluid is pushed by rotating gears. The simplest type of fixed-displacement pump is the gear pump, in which the hydraulic fluid is pushed by rotating gears. Pvc Pipe December 28, 2019 Share: Facebook Twitter Pinterest The simplest type of fixed-displacement pump is the gear pump, in which the hydraulic fluid is pushed by rotating gears. ... Click to read moreOthers news: Another news: