SUCCESS STORIES
The Evolution of High Velocity Thermal Spray: From Shop Applications to Mission Critical Equipment Protection © IGS
Back in the 1995, high velocity thermal spray was used for specialized applications in aircraft components, valves and other similar equipment.
B
ack in the 1995, high velocity thermal spray was an established
gas stream was the ȴrst piece of the puzzle. This technical development
technology in a highly controlled shop application environment. It was
delivered a surface technology that worked well with commonly used
used for specialized applications in aircraft components, valves and other
welding materials in high temperature corrosion environments such as in
similar equipment. Users of the technology started to ask whether it could
the Pulp&Paper and Coal Power sectors of the time.
be eectively applied in the ȴeld, to existing ȴxed assets in-situ. Field technology was also present at the time, however, it was a dierent
New hurdles
class of technology. Twin wire arc spray (TWAS) or thermal spray
At that stage IGS, with key clients, was exploring the wider utilization of
aluminium (TSA), are both low velocity thermal spray technologies that are
the technology into other industry sectors such as the upstream O&G
not able to produce reliable coatings to serve in critical erosion/corrosion
industry. They soon discovered that spraying o-the-shelf alloy feedstock
environments in ȴxed assets such as process vessels, towers, columns
materials using a high velocity process, produced particles that oxidized
or power boilers. The existing high velocity thermal spray equipment and
in ȵight creating an applied microstructure with permeability pathways
technology couldn’t be taken into the ȴeld eectively or economically.
for corrosion. While this wasn’t an issue for high temperature erosion applications, it was a fundamental problem for environments with corrosive
Solution identified
media e.g. Chlorine or Sulfur, among other corrosive substances (Fig. 1).
Around 1995 a handful of engineers addressed that problem and took high velocity thermal spray technology into the ȴeld. It was successfully
Material development
deployed in the downstream oil and gas industry, originally in South
Signiȴcant Research and Development work was then undertaken by
Africa, and in the late 1990s this technology went global, being adopted by
IGS in the early 2000s into developing new high velocity thermal spray
multinational energy corporations.
feedstock materials, which would control the alloy integrity during the
High Velocity Thermal Spray (HVTS), also known as the High Velocity Alloy
application process. This way the applied microstructure would be ȴt for
Cladding, has continued to evolve. Atomizing the wire in a supersonic
the service environment of the asset. The R&D project focused on the
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N.32 - 2019 DECEMBER - ipcm® Protective Coatings