What effect does the hole design of the drawing machine have on the drawing effect and equipment?

What effect does the hole design of the drawing machine have on the drawing effect and equipment?

The drawing die hole pattern in the drawing machine is generally divided into a curve (R type series) and a linear type (taper type series). From the perspective of the material's uniform deformation in the drawing die, it seems that the curve type is better than the straight type, because this hole type is designed based on the theoretical guidance of 'smooth transition'. The hole structure can be divided into five parts:"entrance zone","lubrication zone","working zone","sizing zone"and"exit zone"according to the nature of work.Grind the entire hole into a large,isolated surface with different curvature.This hole-shaped mold is still applicable under the condition of the drawing speed at that time.

In order to meet the requirements of high-speed wire drawing and ensure the service life of the wire drawing machine,the "linear" theory was born.This theory focused on the lubrication and wear factors during the drawing process,and pointed out the improved linear wire drawing die hole type should have certain characteristics.

The longitudinal section lines of each part of the hole pattern must be straight,and the drawing force of the straight working cone surface is small;the junction of each part of the drawing machine die must be obvious,so that each part can fully play its role and avoid the transition angle The reduction of the actual length of the sizing area.
Extend the height of the entrance area and working area so that the wire enters the middle section of the working cone of the die hole, and use the wedge area formed by the entrance cone angle and the upper half of the working cone angle to establish a "wedge effect" to form a denser and stronger lubrication on the surface of the wire,reduces wear and tear and is suitable for high-speed drawing.

The sizing area must be straight and of reasonable length.If the sizing area is too long, the friction of the wire will increase.After the wire is pulled out of the die hole,it will easily cause diameter reduction or wire breakage.If the sizing area is too short,it will be difficult to obtain wire with stable shape,accurate size and good surface quality and will wear out very quickly. Practical application shows that the wire drawing die designed by the linear theory conforms to the wire drawing production rate requirements of the modern wire drawing machine and the service life is more than 3-5 times higher than that of the R wire drawing die.