All pumps cause the flow (flow). The principle of operation is called displacement “in which a liquid or fluid is taken and transferred to another place. In general, pumps convert mechanical energy into hydraulic fluid power. While the definition of displacement is the volume of liquid is transferred each cycle (rotation) of the pump.
Classification of pumps.
Hirolik pump basically classified into:
  1. Non-positive displacement
    The meaning of the positive displacement pump is when NON pump characteristics:
    • Internal large leakage.
    • The change in pressure has a considerable influence on the capacity
  2. Positive displacement.
    The meaning of the positive displacement pump is when the pump has the characteristics:
    • Internal leakage of small (to get this made SEAL or precision).
    • Changes in the small effect of pressure on capacity (with the establishment of precision / SEAL, going against leakage when the pressure rises).
Positive displacement pump is divided into several types, namely:
  1. Gear pump: is cheap, has a long durability (durable), a simple operation. But the drawback is to have low efficiency, because the nature of air-displacement pump that remains, and is more suitable for use at pressures below 20 MPa (3000 psi).
  2. Vane pump: cheap and simple, low maintenance costs, and whether to produce a high flow with low pressure.
  3. Axial piston hydraulic pump pump. One kind of interest is the axial piston pump. These pumps can also type swashplate or checkball. This type of pump is designed to be work at varying displacement, so as to produce a flow and pressure of hydraulic fluid which varies according to need. The most widely used is the pump swashplate. These pumps can we change its angle swashplate piston to produce a variety of steps per rotation. Larger angel will produce a larger flow rate with the pressure of the smaller, and vice versa.
  4. Radial Piston Pump: used to generate high pressure hydraulic fluid to the low flow rates.

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