Ocean Team has developed a “Wave Compensated Oil Conversion and Flushing System” for offshore and onshore wind turbines. Our new system ensures optimum gear cleaning and oil change quickly, efficiently and safely with the least possible risk of oil spillage.

A wind turbine manufacturer asked Ocean Team to design a way of changing gear oil in a number of newly built offshore turbines at Horns Rev, where the work was to be performed 80-90 metres above sea level. The traditional method, where drums containing the old oil are lowered in wires from the top, is a time-consuming process with a high risk of oil being spilt into the water. We therefore developed a method which is safe for the environment, is more efficient and allows gear system cleaning and oil change to be performed in a single operation.

After doing some research, checking all requirements of the authorities and evaluating possible risks, we designed a completely new method. Our method consists of sending a “twin hose” up to the gear system containing both flow and return. The new oil is heated and filtered on the ship before being pumped up to the gear. A soft “sleeve” is pulled over the twin hose, partly to protect the tower shell from scratches and dents in heavy weather and partly to protect against sea pollution should the twin hose leak (double protection). As the sleeve is rolled onto a wave-compensated hose reel, it compensates for the rocking of the ship, preventing the twin-hose from bursting. Last but not least, the sleeve is equipped with a patented weak-link, leakage-free valve hose system designed to prevent injury to personnel or damage to wind turbine, ship or equipment should the process get out of control.

The method provides much safer and quicker oil change and gear cleaning than conventional methods.