Turbines are exposed to harsh environments which make them susceptible to corrosion, wear and erosion, amongst other factors. Atmospheric corrosion causes damage to wind turbines. This is why manufacturer's use thermal sprayed zinc or zinc/aluminium alloys as a method of corrosion protection. The Metal Spraying process can be completed both manually as well as automatically. The Metal Spray process provides anti-corrosive, as well as restoration methods in order to ensure that the turbines and wind farms are operating efficiently and consistently.
Steam and Land-Based Turbines
Steam and land-based turbines owe their operating efficiency to Metal/Thermal Spray. The video below shows a HVAF system spraying a WC-Co-Cr coating being applied on-site onto steam turbine blades in order to protect them from droplet erosion.
Almost every component of the gas turbine engine has some type of coating on it to prevent the damage caused by wear and temperature. HVAF and HVOF coatings are used in the hot section of the engine to coat the shroud with high temperature metals that will not damage the edge of the engine’s turbine blades, yet provide the tight clearance necessary for the engine to function properly. HVAF and HVOF coatings are also applied to the rotating sleeves or bearing found in the hot section of the engine. Common coatings used in this application include T-800 and Chromium Carbide Nickel Chrome coatings.
Wind Turbines can be subject to harsh salt water environments sometimes installed out at sea or on the shore line a protective coating of Zinc or Aluminium or an alloy of the both gives the corrosion resistance vital to its survival. Arc Spray systems manually and automatically apply corrosion protection coatings to wind turbine towers and components on land and sea.
The above video shows the zinc Arc spray coating process of wind towers (turbines) from blast, thermal spray zinc, prime and top coat.
Pelton Buckets suffer high wear on the internal surface due to silt erosion and cracking on the thinner bucket surface areas cause an imbalance in operation. These are protected by HVOF Spraying or Arc Spraying with 420 Stainless Steel.