Luminous jet leaving a plasma, HVOF or flame gun, with the powder stream visible as a brighter trail inside it. Experienced sprayers read the plume's color, length, shape and stability for problems: a flickering plume points to pulsing feed, a stream that veers off the axis means bad injection, and visible shock diamonds in an HVOF jet show supersonic flow.
Look at the plume, the powder's riding the top edge, the injector must have shifted on the gun.
Also heard as
- jet
- flame
- plasma jet
- spray stream
Related terms
Carrier gas
The gas stream, usually argon, that carries powder from the feeder through the hose into the spray jet.
Pulsing
Uneven powder delivery that makes the spray stream surge and flicker instead of flowing steadily.
Particle diagnostics
Sensors that measure the temperature, speed and size of particles in flight to monitor the spray process.
Standoff distance
The distance from the gun exit to the surface being sprayed, which sets how hot and fast particles arrive.