High-Speed Arc Spraying Technology
Arc spraying, also known as arc wire-spraying, is a coating process by which an electric arc is used to melt two consumable wires and then spray the molten metal onto the parts surface. This process is suitable for parts that require both large thicknesses of material and cost-effective coatings production. The molten metal particles that make up the coating are harder and more resistant than traditional spray coating methods, making them ideal for heavy-duty industrial applications.
High-speed arc spraying is a process where high-density, high-velocity particles are generated through an arc and then propelled onto the substrate. Due to the higher velocity and density, high-speed arc spraying achieves greater coverage and deposition. This makes it possible to coat large substrates or substrates with difficult-to-reach sites, in addition to creating superior corrosion and wear resistance properties.
The high-speed arc spraying process starts with a robotic automation setup that feeds two wires of different compositions, such as steel and bronze, into a gun. The wires are situated opposite of each other in the gun, and an arc is generated between the two. The current and arc gap control the melting process, with droplets of molten metal forming at the guns nozzle. The drops are directed onto the substrate, where they flatten and spread out across the surface.
The backing plates that form the basis of the arc spraying setup are made of titanium. Titanium is the standard choice because it offers superior thermal stability and provides a reliable current path. As the wires move through the gun, their consistency is measured with a non-contact fiber-optic sensor, which senses the rate at which droplets are formed. This helps to ensure a consistent spray rate. For further control of the spray quality, the distance between the arcs, the spray rate and the current level can be adjusted as necessary.
High-speed arc spraying is particularly well-suited for industrial applications involving the following:
• Corrosion and wear protection. This process thickly deposits coating layers with superior corrosion and wear protection, making it an ideal choice for parts that experience extreme wear or corrosion.
• Covering large areas. Compared to other spraying methods, high-speed arc spraying can cover larger areas much faster.
• Working with difficult-to-reach sites. This method is effective for coating parts that have intricate features or that are difficult to access.
It is important to note that high-speed arc spraying requires special safety protocols and personal protective equipment to protect operators from its intense heat, fire risk and dust generated by the process.
High-speed arc spraying offers an effective, efficient and cost-effective method of coating parts with superior corrosion and wear protection. This technology is beginning to supplant traditional spray coating methods in industrial applications, such as those requiring heavy-duty protection. With the right safety protocols and personnel in place, it is an excellent choice for industrial operations.
