• Hydraulic Motors (MR Series) - Approved Hydraulics Limited
    Regular price From £121.34
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    Hydraulic Motors (MR Series)

    Key Features

    • Series: mr high torque
    • Design: gerotor ; geroler low speed high torque motor
    • Mounting: industry standard flanges ; shaft options
    • Use: conveyors ; winches ; agricultural ; forestry ; cranes
    • Ports: side ports ; case drain where required
    Regular price From £121.34
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    • Delivery to UK & Ireland
    • Order by 3pm for Next Day Delivery
  • Hydraulic Motors (MSY Series) - Approved Hydraulics Limited
    Regular price From £228.79
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    • Delivery to UK & Ireland

    Hydraulic Motors (MSY Series)

    Key Features

    • Series: msy high torque
    • Design: gerotor ; geroler low speed high torque motor
    • Mounting: industry standard flanges ; shaft options
    • Use: conveyors ; winches ; agricultural ; forestry ; cranes
    • Ports: side ports ; case drain where required
    • Displacements: 80 cc to 475 cc
    Regular price From £228.79
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    • Delivery to UK & Ireland
    • Order by 3pm for Next Day Delivery
  • Hydraulic Motors (MT Series)
    Regular price From £399.03
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    Hydraulic Motors (MT Series)

    Key Features

    • Design: geroler ; shaft distribution flow
    • Mounting: 4 bolt flange
    • Characteristics: smooth operation ; high efficiency ; long life
    • Displacements: multiple options per series
    • Applications: winches ; conveyors ; augers ; slew drives
    Regular price From £399.03
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    • Delivery to UK & Ireland
    • Order by 3pm for Next Day Delivery
  • Hydraulic Motors (MV Series)
    Regular price From £403.48
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    • Delivery to UK & Ireland

    Hydraulic Motors (MV Series)

    Key Features

    • Series: mv high torque
    • Design: gerotor ; geroler low speed high torque motor
    • Mounting: industry standard flanges ; shaft options
    • Use: conveyors ; winches ; agricultural ; forestry ; cranes
    • Ports: side ports ; case drain where required
    • Features: tapered roller bearings for high radial ; axial loads
    • Displacements: 315 cc to 800 cc
    Regular price From £403.48
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    • Delivery to UK & Ireland
    • Order by 3pm for Next Day Delivery
  • Adam Hindle

    Sales Director

    I began my engineering career at Stockport College in around 2005, first completing a National Diploma in Electrical Engineering, followed by a Higher National Diploma in Mechanical Engineering. I then progressed to the University of Salford, where I earned a BEng (Hons) degree in Mechanical Engineering.

    After graduating, I started my professional career with Approved Hydraulics. I initially gained a combination of hands-on workshop experience and telephone-based sales experience. In later years, I moved into a full-time sales role and led the new crane and excavator attachments department that the company had recently established.

  • Hydraulic Motors (MM Series)
    Regular price From £97.08
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    • Delivery to UK & Ireland

    Hydraulic Motors (MM Series)

    Key Features

    • Series: mm compact
    • Design: gerotor ; geroler low speed high torque motor
    • Mounting: industry standard flanges ; shaft options
    • Use: conveyors ; winches ; agricultural ; forestry ; cranes
    • Ports: side ports ; case drain where required
    • Features: shaft distribution flow ; compact volume ; low weight
    Regular price From £97.08
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    • Delivery to UK & Ireland
    • Order by 3pm for Next Day Delivery
  • Hydra Part Hydraulic Motors (MP Series) - Approved Hydraulics
    Regular price From £149.40
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    • Delivery to UK & Ireland

    Hydraulic Motors (MP Series)

    Key Features

    • Series: mp high torque
    • Design: gerotor ; geroler low speed high torque motor
    • Mounting: industry standard flanges ; shaft options
    • Use: conveyors ; winches ; agricultural ; forestry ; cranes
    • Ports: side ports ; case drain where required
    Regular price From £149.40
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    • Delivery to UK & Ireland
    • Order by 3pm for Next Day Delivery
  • Hydra Part BK2 Series Hydraulic Motor Brake System - Approved Hydraulics
    Regular price £249.52
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    • Delivery to UK & Ireland

    BK2 Series Hydraulic Motor Brake System

    Key Features

    • Notes: Specification information is limited in source listing; confirm dimensions and compatibility before purchase
    • Notes: Details not stated
    • Notes: Details not stated
    • Notes: Details not stated
    • Notes: Details not stated
    Regular price £249.52
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    • Delivery to UK & Ireland
    • Order by 3pm for Next Day Delivery
  • Motor Seal Kits (ZHE Model)

    POA

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    • Delivery to UK & Ireland

    Motor Seal Kits (ZHE Model)

    Key Features

    • Compatibility: Hydra Part orbital motors ; ZHE model
    • Motor series: MR ; MV
    • Function: Service kit to renew shaft and housing seals ; restore leak tightness
    • Intended fluid: Mineral hydraulic oils to ISO 11158 HM ; HLP
    • Typical maintenance: Replace aged O-rings ; shaft seal when oil leakage or dust ingress occurs
    • Applications: Orbital motors on mobile equipment ; agricultural implements ; conveyors

    POA

    • Large UK Stock
    • 1 Year Limited Manufacturers Warranty
    • Bespoke Technical Advice

High Torque Hydraulic Motors

Hydra Part Hydraulic motors are manufactured at one of the worlds largest hydraulic motors factories. They are made using the latest CNC machines and tolerance checked by the best German testing machine on the market.

The range includes the most common motor styles in the Industry including MM motors, MP motors, MR motors, MS motors and MV motors in a complete range of displacements from 8cc to 800cc

Approved Hydraulics have the ability to change shafts in house quickly and efficiently to suit customer needs.

Common Calculations FAQs

Calculating force, speed, pressure, power, and efficiency in hydraulic applications.

How do you calculate actuator speed?

Actuator speed is determined by flow rate and cross-sectional area:

Speed = Flow rate ÷ Area

Flow rate is the volume of fluid delivered (in L/min or GPM).

Area is the cross-sectional area of the actuator piston: π × (diameter ÷ 2)².

How do you calculate cylinder force?

Cylinder force can be calculated using:

Force = Pressure × Area

Pressure is the system pressure (in psi or bar).

Area is the cross-sectional area of the cylinder bore (in square inches or square centimeters).

Area = π × (bore diameter ÷ 2)².

How do you calculate pressure drop across a valve?

Pressure drop can be calculated using the valve flow coefficient (Cv):

Pressure Drop (ΔP) = (Flow Rate)² ÷ (Cv² × Fluid Density)

Flow Rate is the fluid flow (in GPM or L/min).

Cv is the valve flow coefficient.

Fluid Density is the density of the hydraulic fluid.

How do you size an accumulator?

Accumulator sizing considers required flow, pressure, and pre-charge:

Accumulator Volume = Flow Rate × Time ÷ Pressure

This determines how much fluid must be stored to maintain system pressure.

How to convert psi to bar?

Use the conversion factor: 1 bar = 14.5 psi.

To convert psi to bar, divide psi by 14.5.

Example: 200 psi ÷ 14.5 = 13.79 bar.

What is pre-charge pressure in an accumulator?

Pre-charge pressure is the initial gas pressure in the accumulator before fluid enters.

It helps maintain system pressure as the accumulator discharges.

Typically set to 70–80% of system operating pressure.

What is specific gravity of hydraulic fluid?

Specific gravity is the ratio of hydraulic fluid density to water.

A value of 1 means equal density.

Less than 1 means the fluid floats; greater than 1 means it sinks.

What is torque in a hydraulic motor?

Torque is the rotational force produced based on system pressure and motor displacement:

Torque = Pressure × Displacement ÷ 2π

Pressure is the operating system pressure.

Displacement is the volume displaced per revolution (in cubic inches or cubic centimeters).

What unit is hydraulic power measured in?

Hydraulic power is measured in horsepower (HP) or kilowatts (kW).

Hydraulic horsepower can be calculated using:

HP = (Pressure (psi) × Flow rate (GPM)) ÷ 1714.

What’s the relationship between pump speed and flow?

Flow rate is directly proportional to pump speed.

If pump speed doubles, flow rate doubles (assuming constant displacement).

This is important when adjusting flow or selecting a pump for varying speeds.