Hydraulic pumps are
used to shift oil from a tank to the other parts of the system by raising oil
pressure to the required level. A three phase AC induction motor is used to
drive hydraulic pumps. The two basic types of hydraulic pump are hydrodynamic
pump and positive displacement pump. Positive displacement pumps are further
divided into three categories: gear pumps, vane pumps and piston pumps. Gear
pump is a simple pump with only two moving parts. These parts move at constant
speed and are nonreciprocating experiencing uniform force. The factors used for
the determination of pump displacement are fluid volume between each pair of
teeth, number of teeth and rotation speed. The leakage problem is a main
concern in gear pumps. This can be minimized by using vane pumps. Here spring
loaded vanes slotted into a driven rotor is used. But the vane pumps have
disadvantages like lower capacity and pressure ratings. Piston pumps are simple
single cylinder pumps similar to a motor car engine.
No comments:
Post a Comment