The Endurance E-3120 wind turbine is fitted with a Siemens WD5008A gearbox, this provides the necessary speed increase from the rotor (43 rpm) to the generator (1,500 rpm).
As the turbines age we are starting to see various issues occurring.
These issues can range from leaking oil seals, bearing wear, keyways bruising, or more seriously gear failure.
The gearbox has to work hard on the E-3120, it has a nominal rating of 50kW compared to turbine outputs of 60-80kW and the braking events are harsh.
We are delighted that we can now offer our customers rapid and cost effective solutions for gearbox overhaul and repair.
The gearbox has a torque limit of 1,250Nm on the high speed shaft, and the standard Endurance braking system has a specification of 900-1100Nm. DC21 always try to keep turbines at the lower end of this range to minimise wear and tear.
DC21 have worked with a local gearbox specialist with over 90 years experience in power transmission, to offer our customers the most cost effective solutions for gearbox overhaul and repair. We hold complete gear sets in stock to enable a rapid repair.
A new gearbox from Siemens has a lead time of 22 weeks. We can overhaul an E-3120 gearbox in just 2 to 3 weeks.
Within the casing of the gearbox there are three reductions pairs (gear and pinion). Experience to date is suggesting that the 2nd and 3rd reduction pairs are most vulnerable to failure of the teeth. So far we have seen no major issues on the 1st reduction pair.
The low speed shaft that delivers the power from the rotor/blades is connected to the gearbox via a hollow shaft and shrink disc arrangement. Again due to the duties the turbine asks of the gearbox it is not uncommon to find the low speed shaft has spun and friction welded to the hollow shaft. The key way in the hollow shaft can also become bruised.
We are pleased to be able to offer an upgraded hollow shaft with an additional key way to improve the longevity of any replacement.
Normal lead time for gear manufacture is 10-12 weeks, in response to the issues we are seeing we have made the decision to hold stock of several complete gear sets. This now means we can overhaul a gearbox in around 2-3 weeks.
Please feel free to contact us if you would like to know more about our highly competitive endurance wind turbine upgrade and repair services.