What is a Hydraulic Pump?

Last updated: April 2024

Almost every hydraulic system will include a hydraulic pump. But how important is the hydraulic pump within a system and what exactly does it do?

There are a wide variety of hydraulic pumps on the market and these vary depending on application, flow required, pressure required and many other factors. Considering these factors when selecting your pump will ensure optimum performance.

It may seem like a basic question to ask what is the purpose of a hydraulic pump but, even to some engineers in the industry the answer is obscured, so:

What does a hydraulic pump do?

A hydraulic pump is the component within a system that converts mechanical power into hydraulic energy. Hydraulic energy is a mixture of both pressure and flow, which enables the system to work.

How does a hydraulic pump work?

Hydraulic energy requires both pressure and flow in order for it to work correctly, performance cannot be achieved without both of them working together. In turn, the function of a hydraulic pump is to push fluid through the machine which in turn will move loads. A pump creates fluid movement, it doesn’t generate pressure. The key thing to remember about hydraulic pumps is that pumps produce flow, and pressure is resistant to flow.

Types of hydraulic pumps:

There is a varied range of hydraulic pumps available to suit your flow/pressure requirements and application type. The 3 most common pump types are; variable, fixed and gear pumps. Below we will briefly explain the functions of the most common hydraulic pumps.

Variable displacement pump

Flow can be varied at a given shaft speed. Typically tend to be more energy efficient because flow and pressure more closely matches load. The most common types being variable piston pumps.

Fixed displacement pump

Flow only varies with shaft speed. Fixed displacement pumps are good for constant flow and pressure applications. The most common types being gear pumps and vane pumps.

Gear pump

Flow is repeatedly moved due to interlocking cogs and gears enclosing a fixed volume and transferring it mechanically. There are two types of gear pumps, internal and external.

How important is a hydraulic pump within a system?

Once you understand what a hydraulic pump is used for, some would say the pump acts as a beating heart of any hydraulic system. This is due to its role of providing flow to other components and producing the flow which allows pressure to be created when there is a resistance to flow. Being a main component within a hydraulic system highlights the importance of its role, even slight damage to a hydraulic pump can affect its performance and efficiency.

How to tell is a hydraulic pump is bad

Sometimes, you might find yourself in a situation where you have to inspect a hydraulic pump for potential problems. There are several methods available to help you detect any issues that could indicate a faulty hydraulic pump.

Loss of Hydraulic Pump Pressure

If the hydraulic system fails to generate enough pressure or if there is a noticeable decrease in pressure while in operation, it may suggest there is an issue with the hydraulic pump.

Reduced Hydraulic Pump Efficiency

If the hydraulic system fails to generate enough pressure or if there is a noticeable decrease in pressure while in operation, there may be a problem with the pump.

Unusual Sounds

If you start hearing strange sounds like grinding, whining, or knocking, it might be a sign that something is not quite right. These noises could indicate internal damage or worn-out components.

Slow Operations

If your hydraulic equipment is moving at a slower pace or behaving unpredictably, it might be an indication of pump failure or problems with the flow of fluid.

Leaking from the Hydraulic Pump

If you spot any noticeable leaks around the pump or anywhere else in the hydraulic system, it’s a clear sign that something is wrong. These leaks can occur at various points such as fittings, seals, or even through cracks in the pump housing. When you come across such leaks, it’s a strong indication that repairs or replacement are necessary.

Hydraulic Pump Overheating

If the hydraulic system is experiencing too much heat, especially in the pump, it could be a sign of inefficiencies or issues with fluid flow. This can result in overheating, which in turn can harm pump parts and lower the system’s performance.

Hydraulic pump maintenance

Maintaining all your hydraulic components is vital. Lack of maintenance could cause great issues to your hydraulic system. Our sister company ARS Anglian Diesels recently wrote an article all about the importance of hydraulic pump maintenance and repair if you would like more information about this subject.

Hydraulic Pump Repair

BSP offer an in-house and on-site hydraulic pump repair and service, so should your pump be deteriorating due to general wear and tear or there’s an issue in your system, contact us and we will be more than happy to assist.

BSP Hydraulics offer a range of hydraulic pumps from some of the leading hydraulics manufacturers. To find out more about which hydraulic pump would suit your requirements, contact us today on 01924 332491 or email sales@bsphydraulics.co.uk. You can also use our new live chat function where our sales engineers would be happy to assist.