Metal wire drawing, drawing is a metal forming process. It used to reduce the cross section(wire diameter/thickness of the area and increase the length. This process is related to the tensile force, which distinguishes it from other metal forming processes (such as extrusion, forging, etc.).

In this process, a work piece with a large cross-section is forced through a mold with a smaller opening, compared to the cross-sectional area of the workpiece. This will plastically deform the workpiece by reducing its cross-sectional area and increasing its length. This process is used to manufacture wires, rods, pipes, etc.

In wire drawing, there is a hole in thecenter of the tapered die, and the included angle of the raw material (Q195) cone is kept between 8 and 24°. As the material is pulled through the cone, the diameter of the material gradually decreases. This also leads to plastic deformation of the material. Due to the wire drawing, the length of the material is significantly increased.

Raw material: Q195 low carbon steel wire. Without Zinc coated. Different raw material include SAE1008 and so on.

2. The wire drawing machine:

The wire diameter: 6.5mm-5.8mm(first time)-5.2mm/5.0mm（second time)-4.7mm(third time)-4.2mm(forth time)-3.7mm（fifth time)-3.2mm-2.8mm-2.4mm-2.2mm-2.0mm

Raw material:

The Raw material in the playground, and has a wire holder connect the metal rack, it is safer and easier to operate. First stripping, the rust remove operates at high speed and twisted wire at different angles to remove the rust on surface.

First drawing:

The Raw material put into the machine, and drawing to the different wire diameter. The box has Brushed metal powder, when the machine operation, the iron wire covered in metal powder. Each drum has different power. The range is 7.5-15, 22-37,and so on.

The details of drawing machine. Each one drum become more and more thinner.

Drawing the iron wire will be collected here. If you need more thinner wire diameter, you can put the wire in the machine again.

Second drawing:

Become the above picture, about 25kg/roll and other packing.

When drawn the Raw material to the different wire diameter. As shown below.

3. What materials are used to make the mold in this process?

(1)When the metal is pulled out, the wire mold will continue to wear.

(2)For this reason, they are made of hard materials such as alloy steel, tungsten carbide and even diamond.

(3)In one pass, the cross-sectional area is reduced by approximately 10-20%.

4. What is process annealing?

Annealing is a heat treatment process that involves heating the material above its recrystallization temperature and then cooling it back to room temperature. The cooling phase of ferrous materials (such as steel) is slower than that of non-ferrous materials (such as brass and copper) to prevent the metal from cracking or becoming brittle.

Many metal processing processes increase the hardness of the material, which makes it more difficult to complete subsequent manufacturing operations. Annealing can improve the ductility of the material and reduce its hardness, so as to obtain better formability and workability. These qualities are essential for many wire applications.

The manufacturing process of the annealing line is as follows:

1.Use steel (usually low carbon steel) to form wire

2.Heat the wire to a temperature higher than the crystallization point of the substrate but lower than its melting point

3.Gradually cool the heated material to below its crystallization point

4.Oiled to prevent rust and facilitate mechanical distribution (for black annealing lines)

Below is a picture of workers preparing for annealing and annealing furnace.

5. How to use an furnace to make black annealed wire?

• The first time when used, it need to be preheated and dried. Heat to 350 degrees, uncovered, and dry for 3-5 hours. 600 degrees for three hours. Put the iron wire into annealing furnace.
• Cover the furnace cover, set the temperature to 850 degrees (the temperature of different wire diameters will vary). Adjust the current to about 200 amperes (recommended value) and burn for 5-7 hours.
• Then lift the pot out of the furnace and place In the insulation well, it is naturally cooled to within 200 degrees. You can take the silk out of the tank.
• The annealing time can be timed, and the recommended time is about 6 hours. (The temperature is raised for 3 hours, the constant temperature is 3 hours, and the temperature is lowered for 2 hours.
• Put the furnace bladder into the heat preservation pit for natural reduction and cooling for about 10 hours.
• It is mentioned that the furnace cover is opened in the wire pit to cool down and the wire is discharged.

Note: Pit foundation, driving, wire and cable purchase by yourself

The photo showing: put the drawn wire into annealing furnace.