CMM-GL Wind Turbine Gearbox Oil Changer

The CMM-GL unit is designed to drain used oil from and pump new oil into wind turbine gearboxes. The unit can also flush the gearbox with special oil. The machine can service main and azimuth gearboxes, as well as blade angle of attack gearboxes.

The unit operates with mineral and synthetic gearbox oils with the following specifications:

  • kinematic viscosity at 40°С  – 8…50 mm2/sec;
  • density at 20°С – 800…950 kg/m3;
  • ISO 4406 purity class – 14 or better.

CMM-GL gearbox oil changer design

The СММ-GL is a trailer with one axle, which supports the control section and the process section. The process section also includes hose reels. Control section doors are equipped with secure locks.

The unit requires an external power source. The CMM-GL is fully automated with a special controller, which manages operation of pumps, valves, capacitance sensors, temperature sensors, flow switches, filters, manometers and flow meters.


Parameter Value
1. Oil output rate, m3/hour, not less than 0,6
2. Oil drain rate, m3/hour, not less than 0,13
3. Output pressure, MPa 1,3
4. Max power consumption, kW 4,1
5. Power supply
– voltage, V (customizable) 380 (240, 400, 480)
– AC frequency, Hz (customizable) 50 (60)
6. Dimensions, mm
– length 3509
– width 1959
– height 1306
7. Empty weight, kg 900

Modes of operation

Used oil drain mode

In this mode, the vacuum pump extracts oil from a gearbox into the vacuum chamber until the chamber is full. Then a gearpump transports the oil to a prepared container.

Gearbox flushing mode

In this mode, oil is supplied by the gearpump to the required elevation (up to 60 meters) and is injected into the gearbox under pressure, washing away the remaining old oil and particulate matter.

New oil supply mode

In this mode, the gearpump supplies oil to the required elevation (up to 60 meters).

Filtration mode

While pumping new or flushing oil into the gearbox, the oil passes through a 15 μm filter for enhanced purity.

Primary advantages

  • high quality of oil change in wind turbine gearboxes;
  • reduction of wind turbine downtime (the oil change takes less than one hour);
  • mobility (transportation around the wind farm by automobile, standard container installation is also possible);
  • collection of oil spills from the gearbox fairing;
  • can pump oil from one container to another;
  • full and easy access for inspection or servicing.