Production Process of the Galvanized Steel Wire
1. Wire Drawing
Wire rods are chosen to comply with related SAE and DIN norms and sustain us to produce directly from high-conductivity (low resistance) ore base wire rod, which do not contain impurities. Accordingly supplied wire rods are accepted after several chemical and physical tests to process.
With regards to the high conductivity demand of the cable industry, our company uses only iron wire rods, which are made from the iron ore(no scrap iron in it).
Raw materials are subject to acceptance inspections and they are drawn at various diameters depending on the demand of client and standard requirements of the product. The steps are of dry and wet drawing stages depending on the diameter of product. At this drawing stage diameter tolerances are very tight in order to serve our customers with very narrow tolerance limits as per their request.
2. Cold Roll
For flat wires; drawn wires are processed through rolling machine with a high precision, resulting with flat wire with requested diameter. At this stage, it is very important to ensure requested dimensions of the wire and the final product is checked in various controls.
The annealing eliminates the tension on the raw material and makes the internal structure available for zinc coating. The annealing method is the latest technology and environment-friendly one; no lead is used at this stage and annealing is achieved by pulling the wires through the annealing furnace.
An industrial material, similar to sand is used at this stage, where by flame sand is heated and wires pass through this sand. Since all the surface of wire touch the sand, wires are equally annealed in every part, which completely surrounds the wire.
4. Zinc Coating (Galvanizing)
There are two types of coating process:
1- Zinc Coating: The surface of wire is coated completely with zinc and this is the most common product type.
2- Zinc-Aluminium Coating: The surface of the product is coated with the mixture of zinc and aluminium. Usually, the ratio of materials is 5 units of Aluminium for every 95 units of zinc.
During the galvanization procedure, the diameter of wire is measured with Laser diameter gauges before the wire is fed into bath and after the wire is fed out the bath. Accordingly the final diameter can be achieved in a narrow limit. The hot zinc on wires when wires come out of the zinc bath is wiped by modern nitrogen wiping system. Coating process is completed with accurately adjusted mass of zinc coating and the final figures are very close to the target values.