Zinc Chromate Plated Bolts
Well zinc can still corrode but it corrodes at a significantly slower rate than other metals and alloys.
Zinc chromate plated bolts. Steel bolts vary under the test with some bolts lasting only three hours. Safer trivalent chromium coatings are becoming. As with cadmium this material is toxic and its use is decreasing. This additional layer passivates the zinc and protects it from white rust.
Yellow plated bolts have to last 600 percent longer before red rust can appear during the same test. For fasteners that need high corrosion or abrasion resistance a chromate conversion coating is applied over the zinc plating for additional resilience. When compared to steel for example zinc corrodes about 30 times more slowly. The clear zinc bolts are required to remain rust free during a salt spray test.
They include nuts and bolts threaded rods structural bolts machine screws wedge anchors washers rivets and more in a variety of types and sizes including metric and inch. Fasteners are used for fastening and securing materials such as wood metal plastic or concrete. Anoop if you use the torque equation t kdp as explained on our torque page the friction coefficient for zinc plated bolts is 0 22 vs 0 25 for galvanized. Therefore zinc serves as a protective barrier for screws.
It increases corrosion resistance and can be colored. Clear zinc bolts have a lower corrosion resistance according to fastenal. Yellow zinc plated 52. If you plug in this value to the equation you will get torque values for zinc fasteners that are roughly 12 lower than galvanized fasteners to achieve the same tension.