Rust and corrosion can shorten the life of a weighbridge. A painted finish is suitable for most industrial applications, but extremely corrosive environments require greater protection. For demanding applications, we offer a galvanized finish for vehicle scales.
Hot-dip galvanizing is a process used to coat steel with a protective layer of zinc. First, the steel surface is prepared by removing oxide and other residue. Then the steel is immersed in a bath of molten zinc at a temperature of about 860°F (460°C) for up to 10 minutes. The exact time depends on the thickness of the metal. Immersing an entire structure ensures that all exposed surfaces are fully coated, including corners and gaps that can be hard to paint. After being removed from the bath, the galvanized steel is allowed to cool and is inspected.
The galvanizing process causes a metallurgical reaction, forming an alloy that acts as a barrier between the steel and the
outside atmosphere. A galvanized coating is sometimes described as self-sacrificing. If the galvanized surface is damaged, the zinc will corrode and deposit the products of its corrosion on the steel surface. This sacrificial action reseals the steel against the atmosphere, effectively preventing it from corroding.
Hot-dip galvanizing has been used for more than 200 years. In most atmospheres, it is capable of providing extremely long-lasting protection. The American Galvanizers Association estimates that no maintenance will be needed for about 70 years.
Since 70 years is far longer than the life span of most vehicle scales, a galvanized weighbridge is essentially maintenance free. Compare galvanizing to the protection that paint provides. Even the best painted finish will begin to wear after several years of exposure to the elements and vehicle traffic. Whenever bare metal is exposed, the paint should be touched up. If its painted finish is not properly maintained, a scale might need to be completely repainted at about 15 years. More frequent maintenance is often needed in corrosive environments.
METTLER TOLEDO offers a galvanized finish as an option for vehicle scales. This tough, abrasion-resistant coating is a reasonably priced solution for a broad range of applications.