BoltPort offers Zinc Phosphate Fasteners build to last for Structural and Heavy Engineering fastening. Most Carbon Steel and High Tensile Fastener grades are supplied with zinc phosphate coatings. We produce zinc phosphate bolts, screws, nuts, stud bolts, threaded rods, washers, etc. in both metric and imperial system.
Zinc phosphate coating is a crystalline conversion coating formed on surface of the metallic fastener with reaction to mildly acidic phosphate liquid to form insoluble phosphate crystals on the surface. These phosphate fasteners can be used with or without applying oil over the surface to facilitate reduction in friction on the threaded part of the fasteners. Moreover applying oil over zinc phosphate coating can be beneficial to provide addition corrosion protection. Zinc phosphate coatings are common over carbon steel structural fasteners or alloy steel high tensile fasteners.
Zinc Phosphate Fasteners appear dark grey or black in color with topcoat of oil or paint, typically used for anti galling purpose or as a basecoat for further coating formulae.