Hydro turbine bearing components machined from Vesconite Hilube have been installed at the Crai Water Turbine and Pollok Sawmill Projects in Wales.
The UK consultant on hydroelectric turbine design and maintenance on the project had first come to hear about Vesconite bearing materials in 2021, when the restoration projects were still in the conception stage.
The company sent an inquiry for wicket gate bushings and wear rings for the two projects.
The scope of the bushing supply increased and Vesconite Bearings was eventually the supplier of all the plain bearing components in the projects, including the guide vane bushings, runner inlet wear rings, several thrust bearings, and the Francis turbine main shaft bearings.
All the parts were delivered in January 2022, installed in the turbines, and despatched to the client in December 2022 after successful factory acceptance tests and some preliminary testing of the bushings under a controlled environment.
Vesconite renewables applications developer Petrus Fourie notes that the previous bearings were made of bronze, but the restoration project necessitated a rethinking of some of the older technology that was in use when the hydro projects were first built.
“People like replacing bronze because they want to eliminate grease from systems in which water is present,” says Fourie.
“Water flushes out the grease ⎻ which pollutes the water. When the grease is flushed out, metal shafts are left unprotected and corrode,” he adds.
Vesconite Hilube bearings are often used in niche hydroelectric applications since they can be machined easily for older equipment with unique designs.
Besides use in huge hydro-power stations, Vesconite Hilube bearing material is also used in smaller projects such as the Crai Project, operated by Welsh Water, and the Pollok Project, operated by the Glasgow Council.
In England and Wales, there are many modest hydro projects that could generate 100 to 150 kW of electricity, as many areas are mountainous with significant rainfall.