TSS, Thermal Spray Services offered for Steam Turbines
The Aerospace industry is one of the first industries that have completely accepted thermal sprayed coatings. In an aircraft engine there are hundreds of key components that are supplied with thermal sprayed coatings. Without the use of these thermal sprayed coatings a turbine will not operate at optimum levels.
A variety of degradation problems exist in aircraft engines as a result of metal to metal wear, fretting, hot corrosion, particle erosion plus others. This degradation is accelerated due to the high temperature conditions involved. Thermal sprayed coatings impart the required surface condition required to increase the life of certain engine components
Thermal spray coating offers the aircraft and stationary gas turbine industries the means to resist many types of environmental damage, including protection from oxidation and corrosion, thermal barrier coatings to improve engine temperature capability, impact, sliding, and fretting wear, and low- and high-temperature erosion and corrosion.
Typical thermal sprayed components in the aerospace industry:
- Turbine blades
- Flame tubes
- HPT outer stationary
- seal Liners
- Etc..
Examples of application problems and solutions
Engine section | Key application problems | solutions | ||
High-pressure turbine |
Environmental oxidation
|
MCrAlYcoatings deposited using plasma spray, HVOF
Abradable coating using plasma spray |
||
Fan |
Wear |
Abradable coatings applied using plasma spray |
||
Combustion |
Thermal barrier |
MCrAlY alloys and thermal spray thermal barrier coatings applied using plasma and HVOF technologies |
||
Compressor |
Erosion |
thermal spray coatings |
||
Bearings and accessories | Wear | Abrasive resistant coatings applied using HVOF technologies |
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Afterburner | Thermal barrier Lubricity |
Thermal spray coatings applied using plasma spray process Lubricity coatings applied using plasma spray |
Common industry problems
Without protective coatings, corrosion adversely affects the performance and durability of components' structural materials.
» In the power generation industries, corrosion can lead to pitting that can compromise the mechanical integrity of rotating compressor blades and vanes.
Corrosion and oxidation also roughen the gas-washed surface of an airfoil, increasing aerodynamic drag and reducing compressor efficiency.
Erosion is the incremental material loss from a solid surface due to mechanical interaction between that surface and a fluid or solid particles.
Erosion is caused by impinging solid particles or water droplets.
» Industrial steam turbines: In compressors, sand erosion can cause loss of compression ratio.
Galling is a severe form of wear, defined by the ASTM G40 standard as "a form of surface damage arising between sliding solids, distinguished by microscopic, usually localized, roughening and the creation of protrusions (i.e., lumps) above the original surface.
Is caused by the interaction of two sliding surfaces under a load.
Movement and plastic deformation lead to the interaction of two materials, sometimes transferring material from one sliding surface to another.
Galling on blades and vanes considerably increases maintenance and repair costs.
Thermal protections for components operating in high-temperature environments are normally needed to ensure both performance and durability.
Our Surface Technologies supplies thermal protective coatings to protect and extend the operating life of your components.
High temperature impacts customer operations across industrial steam turbine industries.
Turbine blades are exposed to process temperatures reaching as high as 1650C, well above the melting temperatures of commonly used high-temperature structural materials, such as the 1300C melting-point for superalloys.
With no thermal protection, extreme temperatures will cause severe oxidation and hot corrosion of combustor and basket components.
Blades and vanes with no protection will lose load-carrying capability, as high temperature lowers the mechanical strength of structural materials.
TSS s.r.l is unique in its ability to work with its customers and provide them with a custom engineered solution for their specific surface engineering requirements.
Due to our vast 30 years experience in the field of thermal spray coatings as well as the capabilities of our laboratory facilities, engineering department, and machining facilities, TSS s.r.l is highly capable of assisting you in any phase of thermal spray coatings.