French utility EDF has upgraded the original shaft seals at the 240 MW La Rance Power Plant in Brittany, France, the world’s first tidal power station.
The plant’s original shaft seals were made of an ultra-high molecular weight polyethylene (UHMWPE) and carbon graphite material. After successful trials, EDF replaced the shaft seals with Thordon’s SXL polymer radial shaft seals.
“For the EDF plant, we came up with an improved radial seal design that would fit into the existing housing… Initial trials were a huge success,” said Axel Swanson, Thordon Bearings’ business development manager – Hydro, Pump & Industrial.
According to Thordon, the SXL seal is unlike traditional shaft seals in that the elastomeric polymer material used is specifically designed to optimize performance. Operating parameters for Thordon SXL segmented shaft seals are generally similar to those for carbon graphite or phenolic seals in terms of maximum interface pressure and almost always reduce leakage. Thordon’s seals can also be designed for use in either radial or axial sealing systems.
EDF’s La Rance Power Plant is one of the world’s largest tidal power stations, with 24 turbines and a peak capacity of 240 MW. Its annual power output is about 500 GWh.
When the La Rance facility opened in November 1966, it was the world’s first-ever tidal power station. It remained the world’s largest until 2011, when South Korea’s 254 MW Sihwa Lake Tidal Power Station started operations.
This article was originally published on Power Engineering International.
