Application Focus: Special coated o-rings for renewable energy application

For optimal performance wind turbines need critical, consistent and reliable data on wind speed and wind direction measurements.

The sensors that provide this must be able to operate continuously for many years and sometimes in the harshest of weather conditions.

The operating conditions can be extremely challenging as the wind turbine sensors (and accompanying electronics) are exposed to fluctuating and extreme environmental changes over the years. Depending on the location of the turbines, temperatures can range from -40°C to +90° C, humidity changes from 0-100%, and they are subject to varying levels of rain, hail, snow, ice, lightning, vibration, sand & dust, corrosion and altitude.

The required life cycle of the sensors was 10+ years and to achieve this a robust protective housing for the electronics and sensors required a series of reliable, consistent, high-quality seals that performed without compromise in challenging conditions. The sensors were subjected to rigorous testing to ensure this life cycle performance, and as a result are IPX6K rated.

Each size of sensor required a set of environmental seals in the separated top and bottom sections. Our engineers worked in conjunction with our customer's intensive testing program and specified o-rings in an EPDM material (which offered exceptional ozone resistance) with a special coating.

The use of this coating provided a number of advantages. It ensured reduced friction during assembly which removed the slightest risk of damage (and therefore compromise of the seal integrity) was avoided. With this reduced friction it meant that no lubricants were required to aid assembly; ensuring a clean installation process and preventing the risk of contamination. The coating was colour coded for identification purposes according to the size of sensor;  this created a foolproof assembly process with no risk of error by operators.