What is a hydraulic pump?
To understand hydraulic motors, it’s useful to understand what hydraulics means.
Hydraulics is a very complicated topic but to put it simply – hydraulics refers to the movement of liquid in a confined space under pressure. The liquid particles are very close together in fact, their proximity is so close that the liquid hardly looks like a liquid.
When it comes to equipment, there are hydraulic cylinders, hydraulic power units, hydraulic pumps and more. Everyday hydraulic systems include the brake system in your car, lifting equipment and wheelchair lifts. Each of these hydraulic systems uses fluid movement (rather than generating power) in order to perform work. Performance varies depending on the resistance present and the type of hydraulic pump you’re using.
Classification of hydraulic driven pumps
There are 2 main types of hydraulic driven pumps. The most common of the 2 types is the positive displacement hydraulic pump.
1. Non-positive displacement pumps
A great benefit of non-positive displacement hydraulic pumps is that they produce continuous flow. However, it does come with a drawback. Non-positive displacement pumps fluctuate considerably with output as the pressure fluctuates. Hydraulic non-positive displacement pumps are seen in centrifugal pumps, multi-stage and propeller pumps.
Often non-positive displacement pumps are used for low pressure application as they have a maximum pressure of 18 – 20 bars.
2. Positive-displacement pumps
With positive displacement hydraulic pumps, flow is generally constant regardless of the changes in pressure. In extreme circumstances, this can result in the pump breaking if it was plugged. Positive displacement pumps are common amongst peristaltic hose pumps, piston pumps and rotary lobes.
Unlike non-positive, positive displacement hydraulic pumps work in high pressure applications, up to 800 bar. Efficiency increases as the pressure increases, making it the hydraulic pump of choice for many.
Advantages of hydraulic driven pumps
- Reduced energy consumption – it’s said that hydraulic driven pump systems are up to 80% more efficient than pneumatic pumps.
- Better runaway control – hydraulic systems have been recalled to be much easier to control, offering better flow manipulation.
- Reduced maintenance costs – due to the process of hydraulic pumps, less strain is placed on the motor resulting in lower maintenance costs.
- Pump power – hydraulic driven pump systems deliver great power and accuracy.
Disadvantages of hydraulic driven pumps
- Hydraulic fluid mess – hydraulic systems can be messy as it can be difficult to prevent leaks. However, this can be prevented through checking the hydraulic system before each use and lubricating when necessary. Change the filter and the pump’s seals when needed.
- Hydraulic safety – overall, hydraulic systems are very safe and easy to use however, with all equipment it’s important the individual using the equipment is trained properly. Incorrect use could lead to the hydraulic lines bursting or damaging leaks.
As hydraulic pumps differ widely between one another, it’s best to consult Pumps Australia before making your buying decision.
Choosing the right hydraulic driven pump
When it comes to selecting the correct hydraulic pump it’s a similar process when choosing other types of pumps such as diesel and petrol. Firstly, you need to determine the task the pump will be used for. Consider whether it’s for fire fighting, transferring, trash or chemical transfer. Once this has been decided, you can narrow down the selection process.
You also want to consider what you’re more comfortable using. If you’re unfamiliar with hydraulic driven pumps, you might want to buy a pump you’re more experienced with depending on the task at hand. Talk with one of our experts for more information and help with selecting the right pump to suit your needs..