vickers hydraulic motor BM, BMV, BMT, BMS, BMR, BMM, BMH

Eaton Vickers (Vickers) BM series and derivative series (BMV, BMT, BMS, BMR, BMM, BMH) are its popular medium and high pressure, high-performance cycloid hydraulic motor product line.These motors are known for their compact structure, excellent low-speed performance, high starting torque and good reliability, and are widely used in various industrial and mobile devices.
The following are the core features and main differences of these series：
Core common features (based on cycloid principle)
Cycloid meshing pair: The core adopts the cycloid meshing principle of the inner ring gear (stator) and the outer gear (rotor) to produce rotational movement through volume changes.
Axial flow distribution: The distribution of high and low pressure oil is carried out through a precision flow distribution shaft (or flow distribution disc), which has a compact structure and less leakage.
High power density: Under the same displacement and torque output, the volume and weight are significantly smaller than gear motors or some plunger motors of the same performance.
Excellent low-speed performance: it can run smoothly at very low speeds (as low as 1 rpm or less) and provide high starting torque (starting efficiency is usually >85%).
Good impact resistance: the rugged design can withstand system pressure shocks and load mutations.
Wide speed range: it is suitable for low-speed and high-torque conditions, and can also adapt to a certain range of high-speed operation.
A variety of displacement options are available: covering a wide range from tens of ml/rpm to hundreds of ml/rpm.
A variety of installation and connection methods: various options such as shaft extension (flat key, spline), hub, flange, etc. are provided for easy integration.
High reliability & durability: the design is mature, durable, and the maintenance requirements are relatively low.
The main differences and focus of each series
BM series: Basic series/standard series. It provides a wide range of displacement ranges and configuration options to meet the needs of most general-purpose applications.It is the cornerstone of Wiggs cycloid motor.
BMV series: Hub motor / wheel motor. This is a special sub-category of the BM series, characterized by the direct integration of the motor inside the wheel or integrated with the wheel hub.Usually has：
Built-in deceleration mechanism (planetary deceleration or cycloid deceleration).
Built-in multi-piece hydraulic release and spring brake.
Directly drive the wheels, eliminating the need for chains, gears or belt drives.
Applications: AGV/AMR, electric/hydraulic forklifts, airport luggage/cargo tractors, golf carts, mobile platforms, etc. where compact and integrated walking drives are required.
BMT series: high pressure/high performance series / Torque lifting series (Torque). Usually refers to models that are optimized on the basis of standard BM to withstand higher working pressure and/or provide higher torque output.May have：
Higher rated working pressure and peak pressure.
Optimized bearing system and sealing design to cope with high pressure.
It may have a slightly increased size or a strengthened internal structure.
Application: Equipment that requires higher power density or operates under higher system pressure.
BMS series: Small displacement series (Small). Usually refers to BM motors with a smaller displacement range, focusing on applications that require compact size and moderate torque.
Application: light conveyor belt drive, small turntable, tool rotation, small agitator, etc.
BMR series: Radial ball plunger motor. This is the key difference! BMR is not a cycloid motor, but a series of medium and high pressure radial ball plunger motors from Wiggs.It uses a completely different working principle：
Principle: Using the hydraulic pressure acting on the plunger (ball or roller), the output shaft is rotated through the curved surface of the cam ring.
Features:
The working pressure is very high (the continuous pressure often reaches 350 bar or higher, and the peak is higher).
High torque and extremely high power density.
Excellent stability at low speed (even better than cycloid motors).
High efficiency (volumetric efficiency and mechanical efficiency).
But usually the cost is higher and the structure is more complicated than that of a cycloid motor.
Applications: Construction machinery (excavator walking/rotating, crane hoisting/rotating), ships (winches, anchorages), metallurgical equipment, injection molding machines, etc. Heavy-duty applications that require ultra-high pressure, high torque, and high-precision control.
BMM series: This series of logos is relatively rare in Wiggs’ official materials.Sometimes it may refer to a BM motor with a specific configuration (such as a specific brake or valve set), or a special model for a specific market/period.You need to check the specific model manual to confirm its meaning.Sometimes it may not be much different from standard BM.
BMH series: High pressure/Heavy Duty series (High Pressure/Heavy Duty). Similar to BMT, but with more emphasis on high-pressure capacity and heavy-duty durability.It usually represents the version with the highest pressure level and the strongest structure in the BM series.
Application: walking drive under harsh working conditions (such as large skid-skid loaders, small excavators), heavy-duty mixing, high-torque rotary drive, etc.

Main application areas
Industrial application:
Conveyor belt/conveyor line drive
Mixer/mixer drive
Turntable/rotary drive
Coiling/uncoiling machine
Machine tool assisted movement
Auxiliary device for injection molding machine
Fan/pump drive (variable speed)
Mobile devices (BM, BMT, BMH, BMV):
Agricultural machinery: tractor auxiliary drive (PTO replacement), harvester component drive, planter, sprayer wheel drive.
Construction machinery: skid-skid loader/compact loader walking drive, small excavator walking/slewing drive, road roller vibrating wheel drive, forklift walking/steering/auxiliary drive.
Material handling: forklift drive, AGV/AMR wheel drive (BMV), tractor drive.
Special vehicles: snowplows, airport ground handling equipment, road maintenance vehicles.
Heavy-duty applications (BMR-radial plunger motor):
Construction machinery: medium and large excavator walking/slewing drive, crane hoist/slewing drive.
Ships: heavy winches, anchors, steering gear.
Metallurgical equipment: auxiliary drive of rolling mill.
Test bench.