Axial Excluder Seal Protects Wind-Turbine Bearings from Debris and Contaminants

SKF has introduced an axial excluder seal that offers a high-performance alternative to conventional rubber seals for protecting the main shaft bearings on wind turbines.

According to the manufacturer, as an advanced first line of defense against any debris or contaminants the wind carries, this new seal  can help operators reduce the risks of bearing failures and associated costs of downtime, repair and lost productivity.

Unlike conventional rubber seals that can be prone to excessive wear and subsequent failure, this axial excluder design (designated HRC1) is made of a proprietary SKF polyurethane material that exhibits excellent resistance to wear, abrasion, UV radiation and ozone.

Key features include a robust sealing lip to help reduce bending and minimize contact area, friction and wear; optimized flexibility and engineering geometry allowing axial displacement of + 2 mm; and integrated grooves to keep the sealing edge properly lubricated. The product also incorporates a stainless steel clamping band with a fast-lock mechanism to facilitate easy up-tower installation and fixation on the shaft in new installations, as well as retrofits.

SKF notes that early field trials have confirmed the HRC1 seal’s performance levels and durability. Seals were installed on 40 separate 2.5 MW turbines operated continuously under real-world conditions. After three months, an initial inspection revealed only normally expected run-in wear, with no dramatic changes six months later.

HRC1 axial displacement seals are available in standard solid and split versions for shaft sizes from 1m to 3m. Custom solutions can be developed.