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Rockfall netting, Rockfall Netting is a wire mesh netting which is used to prevent rocks from falling onto the road, railways and other structures. The mesh is made of galvanized or PVC coated double twisted steel woven wire in acc.with ASTM A641and EN10223-3. Due to the unravelling characteristics of double twist, the mesh can withstand huge forces and will not unravel even if a wire is broken. Rockfall protection netting with a PVC coating can be used in aggressive environments. In addition to galvanization, the steel wire is coated with a PVC layer of a nominal thickness of 0.50 mm. The technical characteristics and the resistance of the PVC to aging meet the relevant standards.Mild Steel Wire All the wires used in rockfall nets and lacing wire have the tensile strength of 38-48kg/mm (54,000-70,000psi) acc.to BS1052/80 and ASTM A641-97. (The figures below are of the wire prior to manufacturing mesh). The tolerances on diameter of zinc coated wire in Table II. The elongation at break is min.12% and test to be carried out on a sample of minimum 30cm (12 in.) long, before manufacturing the mesh. (In accordance with ASTM A370-92) Galvanisation strictly conforms to ASTM A641-97 Class III Soft Temper Coating. Zinc adherence has to be such that when thewire is wrapped around a cylindrical mandrel having 4 times the diameter of the wire, the zinc shall not flake or crack to such an extent that any flake or crack can be removed by simply rubbing with bare fingers.