"Engineered Surfaces for Exceptional Performance"
"Engineered Surfaces for Exceptional Performance"

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The manual AK-HH HVAF equipment sprays powders, heated and accele­rated by the combustion products of the air-fuel gas mixture.

  • When entering the gun, the compressed air cools the gun. Then the preheated air is used for mixing with the fuel gas for combustion.
  • The mixture of pre-heated compressed air and fuel gas flows into the combustion chamber through the orifices of a catalytic ceramic insert.
  • The initial spark plug ignition of the mixture results in the heating of the insert above the mixture’s auto-ignition temperature than the hot insert then continuously ignites the mixture.
  • The spray powder is injected axially into a wide combustion chamber, where the gas flow is very slow, less than 40 m/s (130 ft./sec.)
  • The long residence time and exposure to favorable heat transfer conditions at high gas pressure, allows the powder to heat efficiently in the chamber.
  • As an optional tool for a proper heating, one may inject controlled amounts of a high heat conductivity gas (hydro­gen, helium).
  • The powder leaving the chamber is propelled into the nozzle of chosen length and configuration, where it is accelerated to a velocity that may be from 800 m/s to over 1000 m/s (2,600-3,300+ ft./sec.), dependent on the chosen nozzle and combustion chamber pressure.
  • When impacting a sub­strate, the spray powder particles form a surface coating.