Basic Fundamentals of Hydraulic Pumps You Should Know
Whether you are a technician, construction worker, engineer, or mechanic who works with hydraulic pumps and related systems, there are basic fundamentals you should know in order to ensure you are utilizing the system correctly and achieving proper performance. A hydraulic pump can fall into one of a few basic categories. There are also different types of pumps to consider and many components to know about when planning, implementing, and maintaining hydraulic systems.
A positive displacement pump, used in high-pressure hydraulic systems, controls displacement and speed. In fixed displacement pumps, the output remains constant at a given speed, while variable displacement pumps allow the output to be changed. Non-positive-displacement pumps generate continuous flow for low pressure systems. Output is variable, depending on variations in pressure.
Types of Pumps
There are many different types of pumps, each with its own set of functions and applications. The more common ones include:
- Rotary Impeller Pumps: A rotating component uses energy from the motor to accelerate fluid away from the center of rotation.
- Piston Pumps (radial and axial): A cylinder-inside-a-cylinder design enables hydraulic fluid to be moved via up and down motions.
- Plunger Pumps: Pistons reciprocate within fixed cylinders, and a positive seal between the inlet and outlet supports higher pressures.
- Reciprocating Pumps: As the piston extends, a partial vacuum is created, drawing fluid through the inlet; when it retracts, fluid is forced out of the pump.
- External Gear Pumps: Two identical gears rotate against one another, supported by a shaft; bearings are fixed on both sides of the gears.
- Internal Gear Pumps: An inner gear has one or two fewer teeth than an outer one, allowing a low relative speed and lower rate of wear.
- Screw Pumps: Two helical screw shafts inside the housing guide fluid in a linear direction.
- Lobe Pumps: A rotary, external gear type pump in which lobes are driven through gears outside the chamber.
- Vane Pumps: Compartmentalized vanes on the rotating shaft convey fluid from the pump input to the output.
All hydraulic pumps share common components, but not all have the pump components listed below. Nonetheless, each is important to recognize when comparing pump systems:
- Inlet Valve
- Check Valve
- Outlet Valve
- Load Sense Controls
- Torque Limiter Controls
- Electronic Displacement Controls
- Pressure Valves
- Pressure Compensators
Before working with or using a hydraulic system, always verify what type of pump is being used and familiarize yourself with the controls, parts, and components. If you’re searching for hydraulic pumps for sale or replacement parts, call the hydraulic experts at White House Products, Ltd. at +44 (0) 1475 742500 today!
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