A thermal spray gun is a spraying gun in which the molten liquid of abrasive is sprayed on the subject. This lays down a coating onto the surface of the subject. As the name suggests thermal spray gun means a substance thermally sprayed on the subject.
What Is Thermal Spray
Thermal spraying techniques are coating processes that involve spraying melted (or heated) materials onto a surface. Heat is applied to the feedstock(coating precursor) via electrical (plasma or arc) or chemical means (combustion flame).
When compared to other coating processes such as electroplating, physical and chemical vapor deposition, thermal spraying can provide thick coatings (approximate thickness range is 20 microns to several mm, depending on the process and feedstock) over a large area at a high deposition rate. Metals, alloys, ceramics, plastics, and composites are among the coating materials available for thermal spraying. They are fed as powder or wire, heated to a molten or semi-molten state, and accelerated as micrometer-sized particles towards substrates. Thermal spraying is typically powered by combustion or an electrical arc discharge. Coatings are formed as a result of the accumulation of numerous sprayed particles. The surface may not heat up significantly, allowing flammable substances to be coated.
There are many types of thermal spray gun:-
Metallizing Gun :
In this gun, the metalizing gun of metal takes place with the help of heat. This heat melts the metal wire into the liquid. Then it is sprayed on the surface of the subject. On part of abrasive media, we can take rod, wire, powder to fed inside the gun.
Flame Spray Gun :
Flame Spray Gun spraying usually requires only low-cost equipment. It is suitable for single-piece and series production and can be used in both stationary and mobile configurations. The main applications are corrosion and wear protection. The use of wire or powder depends on the material and the application rate. Zinc, aluminum, and molybdenum are mostly sprayed as wire. Most metal and hard alloys are applied as a powder.
Arc Spray Gun :
In this gun, two arcs of wire are generating with the help of an electric supply anode and cathode. These wires when touched generate the spark which leads to heat to the two-wire. Melts down and sprayed over the subject. It is also called an electric spray gun or arc spray gun.
HVOF Gun :
HVOF Gun stands for High-Velocity Oxy-Fuel. HVOF Gun is a thermal spray system utilizing the combustion of gases or liquid. Combustion gases such as hydrogen and liquid fuel such as kerosene are used. Fuel and oxygen combine and atomize within the combustion area under conditions that monitor the correct combustion mode and pressure required for coating.
Zinc Spray Gun :
In this type of gun different abrasive media can be used for spraying on the subject. Like commonly anti-corrosive abrasive is used for protecting the surface from corrosion. Mainly zinc spray gun, the aluminum spray gun is used.