Orkot® Hydro Bearings

From grinding flour to generating electricity, harnessing nature’s power has helped people to achieve otherwise impossible tasks. The first hydropower project was in Northumberland, England, in 1871, powering a single lightbulb. Today, behemoths such as the Three Gorges Dam supply China with 22.5 GW of power.

A key component of a hydroelectric dam is its bearings. A number are used in a turbine, such as within the distributor ring, wicket gate and main guide. Each of these needs to guarantee long life and smooth running, while preventing leakage. This is why Orkot® bearings are the preferred choice for this kind of application.

“Trelleborg Sealing Solutions has been supplying the hydro industry for more than twenty years. Orkot® is frequently specified in the initial stages of bearing design due to its performance characteristics,” says Alexander Wimmer, Segment Manager for Hydropower Europe at Trelleborg Sealing Solutions.

The bearings are manufactured from Orkot® TXMM and TLMM, two high-performance materials, made from fabric reinforcement and solid lubricants within a thermo setting resin matrix. Capable of handling extreme loads, they demonstrate high ultimate compressive strength and yield strength.

Orkot® materials are also environmentally friendly. They require no lubrication, which could be a source of pollution, and the manufacturing process is completely non-toxic.

Due to being machinable, a range of shapes are possible and manufacturing is cost-efficient. The bearings can be provided with split designs to install without removing the shaft, or multi-groove variants for water-lubricated applications. “Our bearings have been adapted to be used in so many of the turbine’s systems over the years and we’ve got experience working all over the world with different set ups and requirements,” says Alexander. “It gives us the capabilities to provide the correct solutions for the individual.”

One application where Orkot® shows much improved performance is the turbine guide bearing. “The bearings here are not always running fully hydrodynamically, and as such, other bearings won’t perform as well,” says Alexander. “In these kinds of conditions, Orkot® TXMM is an excellent choice, generating less friction and showing much less wear compared to the alternatives.”