Thermal spray gun is used to provide coating both the external and internal surfaces of the substrate to prevent corrosion. In a thermal spray gun process, the coating material can be used in the form of wire, powder, and rod.
In this process, fed material is melted with different processes and impinges on the substrate to protect corrosion. A thermal spray gun is used to increase the life of the substrate and prevent oxidation. Thermal spray coating is used mostly for sea marine and similar exposed equipment.
Types of the thermal spray gun
- Flame spray gun
- Arc spray gun
- Plasma spray gun
- High-velocity oxy-fuel gun
Flame spray gun: In a flame spray gun coating material used in the form of wire, powder, and rod. For melting the material oxygen is used with acetylene or LPG. Compressed air is used to atomized and impinge the material on the substrate with velocity. The gas flow meter is used to maintain the flow of oxygen and fuel.
Arc spray gun: In an arc spray gun fed material is melted with electricity. Material fed between an anode and a cathode and short circuit done to melting the material and compressed air is used to atomize the molten metal.
Plasma spray gun: In plasma spray gun material in the form of powder, wire, and sometimes in the form of liquid. The plasma torch is used to introduce a plasma jet with a high temperature of 10000 k.
High-velocity oxy-fuel: In an HVOF gun a mixture of liquid or gaseous fuel with oxygen is used and fed into the combustion chamber and ignite continuously. In its converging-diverging nozzle is used to impinge molten metal on the substrate. Nozzle increases the velocity of molten material to impinge on the substrate.
Economical Advantage
- Initial equipment cost is low
- With low melting point materials provide high deposition efficiency