WHAT’S THE DIFFERENCE BETWEEN COLD ROLLING AND COLD DRAWING?

 Cold rolling refers to the process of hot rolling sheet at room temperature. Although the process of rolling can also raise the temperature of the plate, it is still considered as Cold Rolling. Cold rolling by hot rolling after continuous cold deformation, produce poor mechanical properties and higher hardness, require annealing to restore its mechanical properties. 

Cold Rolling product refers to the rolling of flat rolled sheet and bars. Cold rolling is processed further in cold reduction mills at room temperature, where the material is cooled followed by annealing and tempers rolling. This process will improves the surface finish and holds tighter tolerances while cannot reduce the thickness of a work piece. Cold Rolled steel coils and sheets are generally used to make products that do not require bending or simple deformation and stretching.

In the term of finishing treatment, cold drawing is referred as a kinds of cold finishing process which increases 40%-60% of the yield and tensile strengths, often eliminating further costly thermal treatments. Cold drawing is not a separate process, It is often used in pipe treatment with the process of polishing and grinding processes together. Cold drawing steel pipe is pulled through the die which reshapes it into a thinner shape while maintaining the same volume. Almost all cold drawn steel pipe are superior in tolerance, concentricity and straightness.

Cold rolling and cold drawing both are similar in term of dimensional accuracy and surface finish. Cold drawing is a necessary process for small-size pipes while pipes with a diameter of more than 150mm, it is not recommended.

Datong Hydrauic provides Cold Drawn Seamless Tube where the surface is stress relieved and annealed. Our cold drawn steel tubing is manufactured and available for a variety of hydraulic cylinder manufacturing and honed barrels where close tolerances and smooth surface finishes are critical.Contact us for more informations.