1. Introduce

Tungsten carbide drawing die is made of a high-quality hard alloy as the core, which has high hardness, good thermal conductivity, and low friction coefficient, suitable for drawing ferrous metal and large-size wire.

The Tungsten carbide (TC) dies are made of high-quality carbide as die core, which has high hardness, good thermal conductivity, and low friction coefficient. Tungsten carbide wire drawing die is simple to make, corrosion resistant, impact resistant, and low price are the significant features of this product, which is suitable for drawing ferrous metals, large size wire, as well as the drawing conditions of poor occasions to use.

2. The Construction of the TC Dies

The structure of the Tungsten carbide die-hole consists of 4 parts: Entrance, Reduction angle, Bearing, and Exit.

2.1 Entrance

The structure of the entrance is conical in shape and is the largest part of the die-hole cross-section. Generally, the entrance with an angle of 30~35° or R=3.5~6 in order to facilitate the entry of the embryo into the die-hole. The full entry of the lubricant into the die cavity, and ensure that the material is not scratched by the entrance of the die hole.

2.2 Reduction angle

The reduction angle is also called the compression area, or deformation area. It is the most important part of the whole die-hole, its function is to make the metal plastic deformation here, the angle and height of the working area are two important parameters of the stretching die.

If the reduction angle is too small, it makes the contact area of the working area increase, cause increasing the friction between the materials and the die-hole. If the working angle is too large, the flow line of the metal in the deformation area will turn sharply, cause making the additional shear deformation to increase.

Meanwhile, it also will cause the tensile force and contact deformation to increase. The larger the angle is, the larger the positive pressure of the die hole unit is, and the lubricant is easily extruded.

The choice of a correct reduction angle is related to the compression rate of the road, the tensile strength of the drawn metal, and the friction coefficient when stretching. When the compression rate increases, the correct reduction angle should be increased. The higher the tensile strength of the drawn metal, the lower the reasonable working angle should be.

The height of the education angle is generally 2.5~3 times the height of the actual deformation zone of the wire. If the reduction angle is too short for the storage of lubricant. It will cause the deterioration of lubrication. The working area is too long, which is bound to cause the waste of material and increase the cost.

Because of this kind of wire drawing die work area, sizing area vertical cross-section contour line are straight, domestic generally called its “linear” hole type of drawing die. The actual deformation length of the wire in the work area reaches more than 50% of the work area height.

2.3 Bearing length

The bearing length is the most suitable shape is cylindrical, the role of the wire is to further obtain and stabilize the precise shape of each size. It can make the drawing die to ensure the accuracy of the drawing wire size and prolong the lifespan of the drawing die.

The drawing die must have a straight section of the sizing zone whose height is 0.35-0.5 times the diameter of the hole (hole diameter of 12mm or less). Considering the elastic deformation of the wire and the drawing direction may not be in a straight line with the center of the drawing die and scratch the wire, affecting the surface finish of the wire and the life of the drawing die.

Generally, we should make the sizing area and the exit area of the connection to eliminate the edge, the height of 0.3 ~ 0.8mm is appropriate, and the angle should be 5 ~ 8 °.

2.4 Exit

The role of the exit area is to prevent the wire from being scratched when pulling out of the die hole and to protect the sizing area from being pulled apart when drawing. The shape is generally conical, with a cone angle of 30~35°, and its height is generally 0.2~0.5 of the diameter of the die hole.

3. The Advantages after comparing with others

3.1 Economical

TC drawing dies have lower prices than other materials dies, they also require less maintenance and can increase productivity. So TC drawing dies is one of the most cost-effective ways.

3.2 Wide application

Ranging from 0.1mm to 30mm, TC drawing dies have different shapes, are used for a wide range of applications, and can withstand high temperatures and pressures. They are also suitable for drawing various types of wire materials.

• Low-carbon steel wire
• Medium-carbon steel wire
• High-carbon steel wire
• Aluminum wire
• Copper wire
• Welding wire
• Stainless steel wire and Spring wire

3.3 Environmentally friendly

At present, with the increase in people’s awareness of environmental protection, the harmful gas generated during acid washing and CVD film preparation has also become one of the key factors for people to pay attention to the products. The production process of tungsten wire drawing die does not require the preparation of CVD film, which is far less polluting to the environment than CVD wire drawing die.