Orbital hydraulic motors MM and MMS are lightweight, small gerotor motors produced by M+S Hydraulic company. They are designed for continiuous work in light conditions. The MM motors can transfer low power at relatively high rotational speed in comparsion with other motors with similar construction. They can reach maximum power up to 3.2 kW.

Rotational speed range: from 20 through 1950 rpm; maximum continuous pressure: up to 105 bar.

The MM motors are characterized by a host of options. Versions with oval flange with two orifices and direct body mounting with 3 bolts are available. Also, the MM hydraulic motors are available with three shaft options – 2 keyed (type C and CK) and one splined shaft SH and with rear or side (type S) oil ports. The cardan shaft rotates distributor valve and transfers mechanical energy from gerotor set to output shaft. The MM hydraulic motor series consists of six models of 8,2 through 50 cm3 displacement and power output up to 3,2 kW.


  • Displacement: 8.2 – 50 cm3/rev;
  • Rotational speed range: 20 – 1950 rpm;
  • Maximum pressure: from 70/125 bar through 105/200 bar (continuous/peak);
  • Maximum power: 2.1 – 3.2 kW.


  • Low start-up pressure;
  • Shaft seal can bear high back pressure
  • The motor can be used in parallel or series configurations;
  • Compact volume and easy installation;
  • The highest permissible rotating speeds among all orbital motors.


These motors are usually used in conveyors, textile machines, machine tools, ventilators, mining machinery, agriculture machinery etc.

Technical data of MM motors812.maj20324050
Displacement [cm3/rev]8,212,92031,84050
Max rotational speed (conti.) [rpm]195015501000630500400
Max rotational speed (inter.) [rpm]244019401250790625500
Max flow [lpm]162020202020
Torque per bar [Nm/bar]0,10,150,240,380,50,64
Max pressure drop conti./peak [bar]105/200105/200105/200105/20082,5/14070/125
Max power conti. [kW]1,82,42,42,41,81,7
Weight [kg]1,922,12,22,32,5