Hydraulic motors perform a role similar to hydraulic cylinders, but instead of producing linear movement they produce rotary output. Pressurized hydraulic fluid enters the motor, acts on internal components, and creates shaft rotation.
A manifold can control the motor's supply and return paths while integrating directional, pressure, check, flow-control, braking, and other functions into a compact hydraulic circuit.
Rotary Motion
How Hydraulic Motors Work
Hydraulic motors convert fluid power into torque and rotation.
Industrial hydraulic motors are used throughout machinery where a hydraulic power source must drive a rotating load.
Fluid entering the motor creates force on internal rotating elements. Fluid then leaves through the opposite port and returns through the hydraulic circuit.
Directional Control
Reversing Hydraulic Motor Direction
Many hydraulic motors can rotate in either direction depending on which motor port receives pressurized fluid.
A directional control valve can reverse the relationship between the supply and return paths, causing motor rotation to reverse.
Integrating that directional valve into a manifold shortens the connection between the valve circuit and other pressure, check, or flow-control functions.
Directional Control Valve Manifolds →Torque & Speed
Pressure, Flow and Motor Performance
Hydraulic motor output depends on both pressure and flow.
Pressure differential across the motor is closely related to available torque, while flow influences rotational speed.
Restrictions in the manifold, directional valve, hose, fittings, filter, or return circuit can reduce the pressure or flow available to the motor.
Drive Systems
Hydraulic Drive Motors
Hydraulic motors can be integrated into drive systems for conveyors, mobile equipment, rotating tools, winches, augers, and other powered mechanisms.
Industrial hydraulic drive motors represent one category of motor used to convert hydraulic power into driven mechanical motion.
Manifold controls can regulate direction, speed, stopping behavior, pressure, and protection around the drive circuit.
Mobile Equipment
Hydraulic Wheel Motors
Mobile equipment can use hydraulic motors near driven wheels or other propulsion components.
Specialized hydraulic wheel motors are associated with applications where hydraulic pressure is converted directly into rotational movement near a wheel or drive location.
Compact manifold assemblies can be valuable on mobile equipment because available space is often limited and hydraulic functions must remain organized near pumps, motors, cylinders, and control valves.
Mobile Equipment Manifolds →Pressure Protection
Protecting Hydraulic Motors From Excess Pressure
Rapid changes in load or motor speed can create demanding pressure conditions in motor circuits.
Pressure-control valves can be incorporated into the manifold to limit or manage pressure according to the needs of the hydraulic system.
Check valves can also control one-way fluid paths or support portions of more complex motor-control circuits.
Return & Drain Circuits
Motor Return Flow and Case Drain Routing
Hydraulic fluid leaving a motor needs a suitable return path toward the reservoir.
Certain motor configurations can also require a separate case-drain connection that carries internal leakage away from the motor housing.
Where applicable, case-drain passages should not be subjected to unintended backpressure from other return circuits.
Filtration
Protecting Hydraulic Motors From Contamination
Hydraulic motors contain moving internal surfaces that can be affected by contaminated fluid.
Filtration and overall system cleanliness help protect motors as well as pumps, valves, and actuators connected to the same circuit.
Manifold Filtration →Engineering
Hydraulic Motor Manifold Design Factors
Applications
Hydraulic Motor Applications
Hydraulic motors can drive conveyors, mobile equipment, winches, fans, augers, mixers, machine tools, reels, rotating attachments, agricultural equipment, construction machinery, and other industrial mechanisms.
Manifold design around the motor depends on required direction, speed, torque, braking, pressure protection, load behavior, and the physical arrangement of the surrounding machine.