Master Technician
CurrentWHAT IS HVOF “HVC”HVOF Stands for High Velocity Oxygen –FuelHVOF is considered a warm process because the surface temperature of the piece part is kept below 205’C (400’ F). The flame combustion approaches 2760’C (5000’F). The flame approaches 2134 m/sec (7000 ft/sec) [2 to 3 times the speed of sound]. DescriptionHVOF is a revolutionary product that greatly extends the life of wear-prone metal parts. HVOF-coated surfaces have a even porosity and constant Rc70 hardness, which significantly retards surface wear caused by friction and rubbing. This best practice describes the procedure used by Empire to prepare and coat a component, the equipment needs to complete the work, and reasons for eliminating the use of chrome coating.ScopeHVOF is ideal for components such as: Cylinder rods, Pump shafts, Motor Shafts, Struts rods, Hoist rods, Hoist tube, and any other application where uniform hardness, corrosion resistance and extended performance are desirable.BackgroundEven when new, most metal coatings reveal micro-cracks under magnification. With time and use, these cracks allow rust and corrosion to invade the surface, adversely the performance and wear life of the component. However, the homogeneous properties inherent in HVOF dramatically retard corrosion, so surfaces, and any seals which come in contact with them, last more than twice as long.ImpactImplementing HVOF Coating will reduce emission of hexavalent chrome and eliminate a toxic environment HVOF coating is five time more corrosive resistant than chrome plate, two time more wear resistant then chrome and it requires a smaller investment than chrome plate, there is less maintenance of equipment, it is environmentally friendly, has less waste disposal, and damaged HVOF coating can be patched rather than recoating the entire part.PowderPowder is made up of Chromium carbide, Nickel & Chromium. With all three of these metal mixed that is what makes the HVOF an Rc63.
