Wire arc-Theory of Operation:
Wire arc spraying is the best choice for all-purpose spraying. Coatings can be applied fast and at low cost. A wide variety of metal coating materials are available from aluminium through to tungsten carbide. Sprayed metal is usually harder than the same metal in wrought form and has higher lubrication properties. Wire arc spray uses two metallic wires as the coating feedstock.
The two wires are electrically charged with opposing polarity and are fed into the arc gun at matched, controlled speeds. When the wires are brought together at the gun, the opposing charges on the wires create enough heat to continuously melt the ends of the wires. Compressed air is used to atomize the now molten material and accelerate it onto the workpiece surface to form the coating. Bond strengths of around 9,000 psi are achievable. In wire arcspray, the weight of coating that can be deposited per unit of time is a function of the electrical power (amperage) of the system and the density and melting point of the wire.
HVOF- Theory of Operation:
The HVOF process efficiently uses high kinetic energy and controlled thermal output to produce dense, low porosity coatings that exhibit high bond strengths, some of which exceed 83 MPa (12,000 PSI), low oxides and extremely fine as-sprayed finishes. The coatings have low residual internal stresses and can be sprayed to a thickness not normally associated with dense, thermal sprayed coatings.
This process uses an oxygen-fuel mixture. The coating material is in powdered form. The fuel gas is mixed with oxygen, ignited and creates sub-sonic gas velocities as the flame leaves the barrel. The ignited gases form a circular flame configuration that surrounds and uniformly heats the powdered spray material as it exits the gun and is propelled to the workpiece surface.
Plasma- Theory of Operation:
Plasma Spray is perhaps the most flexible of all of the thermal spray processes as it can develop sufficient energy to melt any material. Since it uses powder as the coating feedstock, the number of coating materials that can be used in the plasma spray process is almost unlimited.
The plasma gun incorporates a cathode (electrode) and an anode (nozzle) separated by a small gap forming a chamber between the two. DC power is applied to the cathode and arcs across to the anode.
At the same time, gases are passed through the chamber. The powerful arc is sufficient to strip the gases of their electrons and the state of matter known as plasma is formed. As the unstable plasma recombines back to the gaseous state, thermal energy is released. Because of the inherent instability of plasma, the ions in the plasma plume rapidly recombine to the gaseous state and cool.
At the point of recombination, temperatures can be 6,600 °C to 16,600 °C which exceeds the surface temperatures of the sun. When the coating material is injected into the gas plume, it is melted and propelled towards the target substrate. Using this technology we can apply various ceramic coatings for wear and corrosion resistance.
Our workshop can handle the machining of small to large components, using lathes, milling machines, horizontal and vertical borers and radial drilling . Rarely is a job too large to tackle. You should know that most of our clients receive a turn around in under a week so that downtime is minimised.
Our workshop uses cylindrical internal and external grinders and surface grinders. We also diamond grind internal and external diameters. We also can superfinish and belt linish our coatings when a mirror finish is required.
We perform mig, tig , stick, pta and hard facing of various components.