The MachJet is a new generation High Velocity Combustion
Powder Spray System, which provides supersonic spray
velocities, combined with improved heating and melting of
the powder particles. The high velocity technique offers
great advantages where near porosity-free high quality coatings
at the most economical cost are required. This is a low
cost affordable HVOF System, which produces premium quality
coatings combined with ease of use.
MachJet coatings are similar to or comparable to
other High Velocity Spraying Process in terms of:
High Bond Strength
Excellent Wear Resistance
Good Surface Finish - as sprayed
Thick Coatings (if required)
Fine Finishing Capability
The powder is fed through the gun into a fuel gas and oxygen
flame. A stream of compressed air restricts the flame and
blasts the molten powder, producing a fine spray and obtaining
high or supersonic particle velocity. Shock diamonds characteristic
of a supersonic flame are visible in the flame. The compressed
air also does the job of cooling the nozzle air cap assembly.
The MachJet spray gun has been designed and built
to be one of the worlds best hand guns for producing supersonic
spray velocities in flame sprayed coatings with powders. The
standard gun is set up to spray HVOF Grade Powders using Liquefied
Petroleum Gas (LPG), propane, Propylene or Natural Gas as
the fuel gas. Suitable hardware is available for LVOF spraying
using D.A. as fuel gas.
The Control Panel.
The MachJet Control Panel is the heart of the MachJet
HVOF Powder Spray System. It is a precision instrument used
for regulating and measuring the flow of oxygen, fuel gas and
air to the gun. Connected between the gas supply and the gun,
it is the reliable indicator of gas flow and an aid to highest
coating quality. The panel provides three pressure gauges: oxygen,
fuel gas (LPG/Propane) and Air (which has 0-10 Kg/cm2). The
pressure can be preset through the gas regulators and air regulator
fitted on the gas cylinders and air control unit respectively.
The control panel also consists of three flowmeters one each
for oxygen, fuel gas and air to measure the flow of these gases
in SLPM. The flow can be adjusted with the help of needle valves
provided. Input power supply to the Control Panel is 220 V /
1 P / 50 Hz.
There is an interlock between the air flow and fuel gases
which can be preset by a pressure switch located on the
top side of the panel. This interlock prevents ignition
to the gun if the required air pressure is not provided,
avoiding backfire and preventing damage to the gun.
There are two flash back arrestors - one each at the outlet
of oxygen and fuel gases at the bottom of the control
panel. The flash back arrestor at the oxygen outlet will
shut off the oxygen supply if the fuel pressure is higher
than the oxygen, to prevent backfiring. The flash back
arrestor provided at the fuel gas outlet prevents any
flame from entering the control panel.
The MachJet System also consists of specialised
ancillaries such as a dedicated Powder Feeder, matched Hose
Kit and gas and air control units.
Other HVOF Equipment: