CMM-G Wind Turbine Gearbox Oil Changer

The CMM-G unit is designed for a three-stage process of changing oil in wind turbine gearboxes (draining old oil, flushing the gearbox and filling it with new oil). The unit allows for quick and efficient servicing of wind turbine oil system. The unit can be used for servicing wind turbines made by many different manufacturers. The CMM-G can also heat clean oil.

The unit changes mineral and synthetic oil with the following properties:

  • 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-G Oil Changer Unit

Gear Oil Changer

The CMM-G is based on a trailer and consists of housing, clean and used oil tanks and hose drums. The side walls of the housing are equipped with doors for access and servicing. An accessory storage compartment is installed in the left side of the housing. A compartment with a rolling door contains a generator to power the unit if grid connection is unavailable. Process parameters and automatic valves are managed by a controller. The end of the output hose is equipped with an oil meter.




1. Oil output rate, m3/hour, not less than


2. Oil drain rate, m3/hour, not less than


3. Max oil output temperature in heating mode, ºС


4. Output pressure, MPa


5. Oil heater power, kW, max


6. Max power consumption, kW


7. Power source

– voltage, V


– AC frequency, Hz


8. Dimensions, mm, max

– length


– width


– height


9. Empty weight, kg, max


Before switching to a different oil type, do the following:

  • flush the unit to prevent mixing of different oil types (mineral and synthetic);
  • change filter elements

CMM-G Oil Changer Operation Modes

Gear oil Changer

250 gallon/950 liter tanks

Old oil drain mode

In this mode, the unit’s vacuum pump extracts oil from the turbine gearbox into the unit.

Gearbox flush mode

In this mode, flushing oil is supplied to a height of up to 105 meters, and is fed into the gearbox at 5 bar pressure, washing away the remaining used oil and particulate matter.

Heating and filtration mode

This mode is required for quick heating and filtration of clean oil before filling. After heating to 70°С, the oil is supplied to the gearbox.

When heating and filtration mode is engaged, it is possible to simultaneously supply oil to the gearbox and heat the next batch of oil for filling the next turbine.

Clean oil supply mode

In this mode, the unit’s pump supplies oil to a height of up to 105 meters. At the same time, the oil is filtered by 3 and 25 μm filters.


The CMM-G gearbox oil changer offers the following advantages:

  • mobility;
  • harsh climate operation capability;
  • full process automation;
  • automatic correction of oil flow when process conditions change (filter condition, oil feed height etc);
  • draining of oil and filling of new oil takes less than 1 hour;
  • drums are equipped with electric drives for fast hose reeling.


Gearbox Oil Changer 7 inch touch panel

7 inch touch panel

Wind Turbine Automatic hose reeling on drums

Automatic hose reeling on drums

Flow control system

Flow control system

Wind Turbine Smart heating control

Smart heating control

Wind Turbine Generator power

Generator power

2 axle trailer mobile design

2 axle trailer mobile design

Wind Turbine Gearbox Power grid connection capability

Power grid connection capability

Wind Turbine Gearbox Servicing height up to 100 meters

Servicing height up to 100 meters

Wind Turbine Gearbox Full automation

Full automation