High Speed Multi-Stage Drawing Process of Hot-Dip Galvanised Steel Wires

The production of steel wires with zinc coatings is an important branch of the drawing industry, as it allows for steel products to be obtained, characterised by both high mechanical properties and good corrosion resistance. This paper presents unique tests into the production of galvanised steel wires in industrial conditions. The influence of the drawing parameters on the coat and properties, as well as residual stresses in steel wires, are discussed. It has been demonstrated that three phenomena occur during the wire-drawing process at high speeds: namely, zinc sticking to the surface of drawing drums, zinc coating grinding caused by a larger friction surface area between the tool and the material, combined with the detachment of the zinc coating in the calibrating part of the die until the wire breaks and the drawing process is interrupted. After drawing at high speeds (over 15 m/s), the wires are characterised by a thin coat and worse properties, as well as higher internal stresses.