Oerlikon Metco DJ2600

  Spraying process of the unit and cross break of the sprayed layer Copyright: © IOT HVOF spraying process by means of Sulzer Metco DJ2600 (a) and HVOF sprayed WC/Co coating (b)

The DJ2600/2700 HVOF (High-Velocity Oxygen Fuel) thermal spray system is suitable for operation both with hydrogen and with hydrocarbons such as propane, propylene, ethene or natural gas. The fuel/oxygen gas mixture is burned in a combustion chamber and expanded in a convergent-divergent nozzle. In the process, the gas flow reaches a speed several times greater than supersonic speed and accelerates the powder particles which are injected axially into the combustion chamber to a high kinetic energy level. The use of gas-formed fuels results in a very homogenous combustible gas mixture with a high level of process stability. Thanks to their high kinetic energy, the particles flatten itself, as they collide against the component and thereby, they form a very thick coating. The HVOF process is employed for the manufacture of coatings based on metal alloys (e.g. NiCr, 316L, MCrAlY), carbide-reinforced metal matrix composites (e.g. WC/Co, Cr3C2/NiCr) or oxide-reinforced metal alloys (e.g. NiCr/Al2O3) with low surface roughness and reduced residual stresses.

Technical data

Parameter Value
Process gases oxygen, hydrogen, nitrogen
Average particles temperature T = 600 up to 1,800 °C
Average particles speed v = 400 up to 700 m/s