The production process of galvanized steel wires

Galvanized steel wire is drawn from 45 #, 65 #, 70 # and other high-quality carbon structural steel, and then galvanized (electro galvanized or hot galvanized).
Galvanized steel wire is a kind of carbon steel wire galvanized on the surface by hot plating or electroplating. Its properties are the same as those of straightened tempered steel wire. It can be used as unbonded prestressed reinforcement, but it shall be galvanized at least 200~300g per square meter. It is often used as a parallel wire rope for cable-stayed bridges (in addition, flexible cable sleeves are also used as the outer layer of the protective layer).

微信图片_20221206131034

physical property
The surface of galvanized steel wire shall be smooth and clean without cracks, knots, thorns, scars and rust. The galvanized layer is uniform, with strong adhesion, strong corrosion resistance, good toughness and elasticity. The tensile strength shall be between 900 Mpa and 2200 Mpa (wire diameter Φ 0.2mm- Φ 4.4 mm), number of twists( Φ 0.5mm) for more than 20 times and repeated bending for more than 13 times.
The thickness of hot-dip galvanized coating is 250g/m. The corrosion resistance of steel wire is greatly improved.
plan
Galvanized steel wire is mainly used in planting greenhouses, breeding farms, cotton packaging, spring and wire rope manufacturing. It is applicable to engineering structures with poor environmental conditions such as cable-stayed bridges and sewage tanks.

微信图片_20221206131210

Drawing process
Electroplating process before drawing: In order to improve the performance of galvanized steel wire, the process of drawing steel wire into finished products after lead annealing and galvanizing is called electroplating before drawing. The typical process flow is: steel wire – lead quenching – galvanizing – drawing – finished steel wire. Among the drawing methods of galvanized steel wire, the process of first plating and then drawing is the shortest process, which can be used for hot galvanizing or electro galvanizing and then drawing. The mechanical properties of hot dip galvanized steel wire after drawing are better than those of steel wire after drawing. Both can obtain a thin and uniform zinc layer, reduce the consumption of zinc and reduce the load of the galvanizing line.
Drawing process after intermediate plating: the drawing process after intermediate plating is: steel wire – lead quenching – primary drawing – zinc plating – secondary drawing – finished steel wire. The feature of medium plating after drawing is that the lead quenched steel wire is galvanized after drawing once, and then the finished product is drawn twice. Galvanizing is between two drawings, so it is called medium electroplating,. The zinc layer of steel wire produced by medium electroplating and then drawing is thicker than that produced by electroplating and then drawing. The total compressibility (from lead quenching to finished product) of hot-dip galvanized steel wire after electroplating and drawing is higher than that of steel wire after electroplating and drawing.

Mixed plating wire drawing process: in order to produce ultra-high strength (3000 N/mm2) galvanized steel wire, the “mixed plating wire drawing” process shall be adopted. The typical process flow is as follows: lead quenching – primary drawing – pre galvanizing – secondary drawing – final galvanizing – tertiary drawing (dry drawing) – finished steel wire tank drawing. The above process can produce ultra-high strength galvanized steel wire with carbon content of 0.93-0.97%, diameter of 0.26mm and strength of 3921N/mm2. During the drawing process, the zinc layer protects and lubricates the steel wire surface, and the steel wire will not break during the drawing process.


Post time: Dec-06-2022