Thermal Spraying is more effective and durable than common surface treatments, such as nickel, chrome plating, and weld overlay.
With any heavy-duty industrial machinery, wear and tear takes its toll on moving parts. Our Thermal Spraying service restores— and in most cases improves— critical components like piston rods, pump shafts, connecting rods, crossheads, rotor bearing journals and pump housings to factory specs so they can continue to deliver years of reliable service.
As its name suggests, Thermal Spraying technology uses heat and high-velocity to precisely shoot tiny droplets of specialized coating materials onto metal surfaces. This ‘spray welding’ or 'thermal spray coating' process ensures optimal adhesion and longevity.
Thermal spray coatings extend the service life and performance of critical and expensive components. Our quick turnaround time— as low as 24 hours— means downtime is minimized. A wide variety of coating materials enables us to solve specific performance problems.
Based on the application, our expert technicians select the optimal coating material and thermal spray process:
- Electric Arc Spray (twin wire electric arc)
Electric wire arc thermal spraying utilizes the same principles employed in wire arc welding systems. The coating material, in wire form, is electrically charged, then contacted to create an arc.
A high-velocity air stream atomizes and propels molten droplets of metal wire onto the substrate. Typical coating materials include stainless steel, aluminum, bronze, babbitt and other alloys.
Temperature: 10,000 – 12,000°F
Particle Velocity: 500 – 1,000 fps.
- Flame Spray (Oxy-acetylene)
Flame spray, also known as oxy/acetylene combustion spray, is the original thermal spray technique developed about 100 years ago. It combines the basic principles of a welding torch with a high-velocity air stream to propel molten particles onto the substrate.
Often flame spray coatings are fused after being applied to enhance bonding strength and coating density. Typical coating materials include cast iron and nickel-based alloys.
Temperature: 4,600 – 5,200 °F
Particle velocity: 300 – 800 fps.
- Plasma Spray
The plasma spray process (non-transferred arc) feeds inert gasses through a high-frequency arc then is ignited between an anode and a tungsten electrode. As the gasses are ionized, a plasma plume several inches long is created.
We inject the spray material in powder form through a nozzle into the plasma plume, where it instantly melts right before being propelled onto the substrate.
Typical coating materials include ceramics (chrome oxide, aluminum oxide, zirconia, and titania). The gas temperature range is typically 30,000 – 60,000°F with our 1,000 amp rectifier and a particle velocity range of 800 – 1,800 fps.
- HVOF (High-Velocity Oxygen Fuel)
The HVOF process combusts oxygen and one of a select group of ignitable gasses (propylene). The HVOF spray gun has a unique design that produces higher flame temperatures and greater velocities than standard oxy-fuel spray applications.
The result is more thoroughly melted powder and greater kinetic energy available to “flatten” the molten particles of coating material. The HVOF process provides several significant benefits:
- Superior bond strength and coating density
- Excellent wear resistance for extended longevity (ideal for components exposed to harsh environments)
- Superior microhardness compared to other thermal spray technologies
- High adhesion to the substrate; high density with low porosity
- Low residual stress and fewer impurities
- Excellent machinability and surface finishing
Typical coating materials include a wide variety of tungsten carbides. The gas temperature range is typically 5,000 - 6,000°F with a particle velocity range of 2,400 – 3,200 fps.