A dynamic industry..

Worldwide, wind power is the most developed alternative energy source. Growth has been stimulated by rising oil prices, a greater concern with the environment and a growing need for energy. In recent years, the wind industry has installed over 40 GW of new wind power capacity globally. While more mature markets within Europe and North America remain strong, for the first time the majority of that power was situated in developing economies. The largest increases were witnessed in India and China, with substantial growth in Latin America.

Seals are components thought little of, until leaks occur causing costly down time and repairs.Dynamic seals for rotating shafts, found in the gearbox, generator, pitch and yaw systems of a wind turbine, play important roles by retaining lubricant for bearings and excluding contaminants that will destroy bearings. Seals also protect the remote environments that are the homes of many wind farms. Good seals and sealing practices protect these environments from unwanted lubricant leakage and spills.

Since energy generators are the machines where the enrgy losses are very crutial , Alfa Sealing offers sealing solutions with advanced materials which have low cooeficient of friction and better tribological properties.

Demands to seals in wind power plants

  • Plant operating time : 20 – 25 years

  • Operating temperature:-10° C  to +40° C (-30° C CCV)
  • Survival temperature:  -20° C  to  +50° C (-45° C CCV)
  • Humidity:      10%   to 100%
  • Ozone resistance
  • UV resistance
  • Protection against dirt & dust
  • saline, marine air
  • Oil and grease resistance
  • Machine temperature up to 100° C
  • Highest functional reliability
  • Long maintenance intervals

Seals for accumulators


Accumulators act as hydraulic power batteries for safety and energy saving.(highlighted in red below)

Seals: Piston seals with guide rings.

Seals for Main Gear


Main Gear converts the rotation of the blades into a speed suitable for the generator.

Seals : Rotary shaft seals.

Seals for Main Brake

Main Brake assist the turbine in stopping at critical rotor speed or for maintenance.

Seals : wipers, rod seals and guide rings.

Seals for Lock Cylinder

Lock Cylinder locks the rotor blades in order to avoid rotation in strong winds or for maintenance.

Seals: piston seals, guide rings, static seals

Seals for Main Bearing

Main Bearing holds the main shaft in position.

Seals: rotary seals

Seals for Pitch Cylinder

Pitch Cylinder controls the angle at which the rotor blades face the wind.

Seals: piston seals, rod seals, guide rings, scrapers, static seals


 Pitch Cylinder

Seals for Yaw Brake

Yaw Brake keeps the nacelle in a steady position towards the wind.

Seals: rod seals, wear rings, scrapers

Axial shaft seals for main gearboxes

Labyrinth seal for main gearboxes