For a gear pump to work properly, two mechanical gears have to be meshing inside a shared housing. The pump is powered by a prime mover, usually a motor. The drive shaft of the mechanism extends all the way to the gearing chamber and one of the gears is locked to the shaft. As the shaft turns, the gears move and create a pumping action.
The Basic Mechanics
Basic mechanical principles cause two connecting gear wheels to rotate at the same time. Fluid conveyance is taking space between the spur gears, however. This is where the locking and unlocking occurs, and the hydraulic oil used to help lubricate the gears is moved through the gear housing as the gear teeth join and unjoin. Hypothetically, if someone were to cut a cross section into the gear pump while it is in operation, the hydraulic steam would be visible. It would come from the inlet port, move through the dual gears and expel out of the housing from the outlet port.
Examining Gear Pumps
We discussed the shape of a hydraulic device in the last paragraph, but a dual-geared pumping device works in a slightly different way. The fluid doesn’t move through the gears’ midsection, for one. What happens is that the two streams of fluid deviate from one another and move around the rim, past the impeller housing and then flow out the fluid out pipe. This allows the fluid to use the entire housing as it moves. Even dual gears, in the way they move together and separate, the principles differ slightly. The spur wheels are side by side, and they have teeth that are designed to move fluid easily and not necessarily to make mechanical coupling easier. To make this happen, spur wheels may have contoured teeth or may use fewer teeth than normal. How many teeth the wheels have will be determined by how much power output is required and how viscous the fluid is.
These are very efficient fluid pumps, and they can be used as oil pumps, chemical process impellers and as lubrication pumps. Hydraulic gear pumps are designed to work in high pressure and to move very large loads. There are many uses for these types of pumps, but they are almost always used to power hydraulic equipment.