Explain the Bar and Rod Drawing - cold drawing processes

In case of bar drawing, hot drawn bars are at first pickled, washed and coated to prevent oxidation. Once it's done a draw bench is used for process of cold drawing. To make an end possible to enter a drawing die diameter of the rod is reduced by swaging operation. This end is fastened by chains to the draw bench and end is gripped by the jaws of the carriage. In this approach a high surface finish and accuracy dimensionally is obtained. Products of this process can be used directly without any further machining.