Coatings

[ballvalveguy]

I am curious to know the difference between a spray and fuse coating and an HVOF (high velocity oxygen fuel) coating, Can you spray any coating (e.g tungsten carbide, chrome carbide) on to any base metal (410 stainless, Inconel)? How is the process done? What are the advantages of one over the other?

 

[JimCasey]

I ran across this press release just now:


Watson Grinding & Manufacturing Turns to Romi for Turning Valve Components
7/25/2007
Erlanger, KY - Watson Grinding & Manufacturing is riding the oil drilling boom for all its worth down in Houston. This 47-year old company has built its reputation on offering complete turnkey manufacturing of critical oilfield components such as valves, pumps and compressor parts.

The company has developed a variety of thermally-applied coating processes to solve erosion and corrosion problems facing recent petrochemical, oil production and manufacturing industries. During the early 80's, Watson was heavily involved in the development of High-Velocity Oxygen Fuel (HVOF) coatings - which later became known as "Jet Kote." In addition to HVOF coatings, Watson offers High Energy Plasma, Metallizing and Weld Overlay coatings.

For oilfield valves, the type of spray coating chosen depends on the application. For example, HVOF coatings are applied at supersonic velocities to critical valve components where wear and erosion are serious problems. Tungsten carbide, cobalt, nickel and chrome matrixes and chrome carbide coatings are all applied with this process.

Other coatings, such as Chrome Oxide, Aluminum Oxide, Titanium Dioxide, and Zirconium Oxide are used where dielectrics, thermal barriers and corrosion resistance are required.

What makes Watson Grinding & Mfg. unique is their ability to machine, spray coat and then finish valve components (by grinding, lapping or honing) all at one facility. This allows the company to turn parts around faster and more reliably than many suppliers and at very competitive prices.

Valve components are made from raw material or they can be rebuilt from existing parts. Watson can repair most ball valve components including chrome and nickel-plated parts. With today's machine tools, they can hold tighter tolerances and apply the most advanced coatings for a particular job-making the valves better than new.