Defense Holdings Inc. (DHi) has received a contract from H&N Electric for six wind turbine blade pitch-control slip rings. The slip ring systems feature Stemmann units, which have been refurbished and remanufactured to incorporate HiPerCon metal fiber brushes.
While other components of the slip ring require annual lubrication, these new electric brushes are capable of operating for up to five years without maintenance, according to DHi.
The new slip ring is designed to replace the original equipment manufacturer blade pitch-control slip ring in a GE 1.5 MW wind turbine. The first DHi refurbished and remanufactured wind turbine slip ring using HiPerCon's electric brushes was installed in May at PacifiCorp's Leaning Juniper wind farm, located near Arlington, Ore.