Focus on Steel 2018 | Page 36

36 37 The inside story of our cold drawing dies team They are the ones who have succeeded in producing the cold drown dies Four years ago we bought them, today we make them and sell them. With the launch of the Special Profiles Division, one of the greatest challenges was to solve the problem of the cold drawing dies, which were bought at high prices from import market. Today, such dies are manufactured by us at a quality level at least equal to those purchased from experienced external producers. In addition, in-house production of cold drawing dies gives us more flexibility in the production of cold drawn profiles and allows us to develop in a much shorter time, and more economical, the production of new special profiles. We are talking about a very dynamic process. The lack of a spare die can block the entire production. Watch how we manufacture the special profiles on our official YouTube channel! A team led by an experienced tooling engineer, Costel Radoi, helped in design by Cosmin Serghiuta, along with three other tool and die makers, managed to set up the production of cold drawing dies, a very complex and demanding action, which involved a lot of time, nerves and countless tests. "In the initial phase of the project, dies were ordered from European producers, but there was a problem with the last drawing step. That's the reason why we've chose to make our own dies, to buy the proper machinery and start testing until we've got the right products, "said engineer Costel Radoi. The Tooling Division executes dies and set of dies for cold drawing of profile steel bars. Active part of the dies is executed in carbide grades CTM30 (G3/G30 equivalent after ISO), with a hardness of 1120 HV30 inserted in steel treatment body. This parts are made based on the fitting dimension of the die in the cold drawing bench. A number of input data are considered in of input data are considered in the design process, such as: quality of the drawn steel, hardness of it, intended for this purpose. dimension of the raw material, reduction degree required, length of the final product, shape, surface preparing for the cold draw, lubricant used on drawn, the tolerances of the given profile, cold drawn parameters, etc. Also, the cold drawing dies can be made according to the documentation given by the client. The dies are executed on CNC wire electrical discharge machines with 5 axis, after which they are manual polished by specialized personnel, using special tools, diamond powders and suspensions with granulation form 2 μm up to 127 μm, with the help of special tools intended for this purpose.