Cold Drawing Machine
Cold drawing is a process that uses very little heat and is performed at room temperature. It can be used to produce a variety of shapes and sizes of steel bar or coil products. The finished product exhibits a bright and polished finish, improved mechanical properties and precise dimensional tolerances. The process also increases the strength of the material without changing its chemical composition.
During the cold drawing process, a piece of hot-rolled steel is drawn by forcing it through a die with an ID that is smaller than its OD. This reduces the steel’s cross section and shapes its profile. The resulting drawn products have a bright finish and better mechanical properties than rolled, cold-formed, or extruded products.
The cold drawing process requires high-precision machines and skilled operators. The first step in this process is called pointing, where several inches of the lead ends of the rod are crushed and reduced in size to a pointed shape that can pass easily through the drawing dies. This step is necessary because the die openings are always smaller than the original section of the rod or coil.
In order to achieve the desired shape and tolerances for a specific product, the drawn metal must be passed through the dies multiple times. This process is known as multi-pass drawing, and the manipulated metal is generally annealed between each pass to remove cold work and increase ductility.
It is also important to control the drawing forces for optimum performance of the drawn product. To do this, it is common to use strain gauges that measure the actual force exerted on the steel during each drawing cycle. This data is then used to calculate the energy-power parameters of the drawing process. This information can be used to design a drawing route that minimizes the required drawing stress, power consumption and back tension. For this purpose, a mathematical model of the drawing process is developed and implemented in the form of a computer program. This program allows the calculation of the energy-power parameters of the drawing process for an experimental drawing route. The calculated values of these parameters are compared to the experimental ones to confirm their accuracy. The result shows that the calculated values are within 10% of the experimental ones, which is a satisfactory result for the purposes of designing drawing routes. This confirms the validity of the proposed mathematical model of the drawing process. Cold drawing machine