Oerlikon Balzers Customer Magazine

Markets

Protective coating for

water turbines

he demand for energy is constantly increasing, driv-

en by population growth and increasing prosperity

in emerging countries. One of the most environ-

mentally-friendly types of energy generation is the use

of hydropower – using run-of-river hydropower plants

placed directly in the river course which constantly gen-

erate power, or pump-storage power plants (e.g. reser-

voirs), which are used to store energy for release upon

demand – a function of ever increasing importance.

Decisive factor: Economic efficiency

Power plant operators are focused on ever higher turbine

economic efficiency, through extended useful lifetime,

longer inspection cycles and higher efficiency. At the

same time, a growing number of new waterways, previ-

ously deemed too inaccessible, are now being tapped –

often highly sandy rivers or waters with high head. Wear

protection for individual power plant components is thus

a key factor for the success of these projects.

Specialists for all cases

Oerlikon Metco provided the first coatings for Fran-

cis turbines in the 1930’s, and, since the 1980’s, has

protected thousands of turbine runners in hydropower

plants throughout the world with its thermal spray coat-

ings, which can be up to 400 µm (0.4 mm) thick. The

coatings are individually tailored – they are dependent

on machine design, precise operating mode and specific

operation conditions.

Oerlikon Balzers is, then again, a specialist for ex-

tremely thin PVD coatings. Not just cutting tools used to

manufacture turbine parts are coated with BALINIT, but

also bearings or valves in the overall system. The goal

of both applications is to reduce wear caused by friction

and thereby to increase efficiency.

Hydropower turbines are subjected to enormous forces and

damage mechanisms. Over time, erosion and cavitation lead

to major efficiency losses and a marked reduction in useful

lifetime. To hinder this, turbine manufacturers rely on high-

tech coatings from Oerlikon Balzers and Oerlikon Metco.

High-tech for the environment