Hydraulic Motors: Their Types And Uses

Categories: Hydraulic

Hydraulic motors have been around for quite some time now, and their application can vary based on different factors.

These motors are generally used to convert hydraulic pressure into mechanical energy, which can come in the form of speed or torque being transferred to the output shaft.

Continue reading to learn more about hydraulic motors, their types and their uses.

What are Hydraulic Motors?

These are basically used to transform fluid energy to rotary mechanical energy, typically applied to a load via a crankshaft. In simple terms, these are used to convert the kinetic or potential energy of a fluid into mechanical energy. 

If we look at it conceptually, a hydraulic motor could be interchangeable with a hydraulic pump, but they serve entirely different purposes. Because of this, there are many structural differences between them both.

Hydraulic Motors Types:

There are generally three different types of hydraulic motors based on their configuration: piston, gear, and vane.

These motors are interchangeable with the same kind of hydraulic pumps when used to pour a fluid where the hydraulic motor acts as a pump acting on external torque and vice versa.

Hydraulic motors configured differently are meant to serve different purposes so let’s have a closer look at their structural differences:

Piston Motors:

These are available in fixed and variable volume versions. The most common type of motor is also a piston motor called an axial piston pump.

These have a high volume efficiency and are adaptable to various loading conditions. There are generally two types of axial piston hydraulic motors, namely bent axis and swish plate.

However, considering the hydraulic motor price, the bent axis hydraulic motor is usually priced higher than the swish plate, the latter still remains more prevalent than its alternatives.

Gear Motors:

These motors provide moderate efficiency by providing a continuous service at rated power levels. There are several types of gear motors, including differential gear motors, gerotors, and roller-gerotors.

All these variations work with the least possible friction enabling them to produce higher torque. They also have a high tolerance for hydraulic oil contamination, which allows them to be used in dirty environments as well.

Vane Motors:

These types of motors are known for their compact size, simple design, reliability, and overall efficiency. The vane-type motors have the capability to start under high loads thanks to their high starting torque efficiency to hoist winch drives.

However, they do not provide high operating efficiency compared to piston motors, and also, the service life of vane-type motors is usually less than that of piston types. 

What are the Uses of Hydraulic Motors?

These are generally used to generate a rotational force, commonly known as torque. The gears, vanes or pistons attached to the crankshaft of the hydraulic motor is used to convert hydrostatic energy into mechanical energy. The speed and displacement of these motors’ rotation dictate their capacity.

The different hydraulic motor types are used in varied industrial applications, including conveyors, augers, rolling mills, and mixers. These are highly resistant to heat and robust in nature, making them a preferable solution for the job at hand.

Further these can even be used in electric motors without any electricity. Regardless of the environmental conditions, hydraulic motors can function without any hassle.   

Hydraulic motors are ideally designed for any mobile machinery where they are the main drive for numerous off-highway equipment.

In addition, hydrostatic drive systems are meant to transfer the power from the engine to the wheels with unmatched reliability and versatility.

Therefore, most backhole loaders, wheeled loaders, articulating loaders, and even skid-steer loaders leverage the competencies of hydraulic wheel motors. The reason behind this is the seamless reversibility of the motors, making them ideal for the said application. 


What is a hydraulic motor?

It is basically a device that is used to convert a fluid’s kinetic or potential energy into mechanical energy. The energy is converted via a recipient surface area or pressure plate and transferred to a shaft to create rotary motion.

How many types of hydraulic motors are there?

These are mainly classified into three types based on their configuration: piston motors, gear motors, and vane motors. They differ in both their structure and functionality.

How do hydraulic motors work?

The basic principle behind the working of hydraulic motors can be understood as the conversion of the linear kinetic or potential energy of a fluid into a rotary motion by using a pressure surface and a shaft that is rotated to create energy. 

What are hydraulic motors used for?

Motors have a number of applications. They can be seen being implemented in conveyor and feeder drives, roll mills, excavators, and also in high-powered lawnmowers. 

What is the difference between a hydraulic pump and a hydraulic motor? 

Although hydraulic motors and pumps are interchangeable, a motor is an electro-mechanical device used to convert the electrical energy produced by pressure to mechanical energy.
In contrast, a pump is a machine used to transfer fluids using the mechanical energy of suction or pressure.