The main reason for the popularity of cold bent steel sections, also known as profiles, is that compared with hot rolled steel sections, smaller unit mass goes together with higher strength.
Steel section production began at ISD DUNAFERR in 1964 with the installation of two production lines: one for open and one for hollow steel sections.
Currently, the production base of the Profiling Works consists of 2 production lines for open- and 4 production lines for hollow steel sections in three halls equipped with cranes on an area of 15 000 m². This capacity enables the production of almost 180 thousand tons of steel sections.
The organizations within ISD DUNAFERR Company Group provide the base material required for steel section production. The self-owned strip slitting line integrated into the technological process makes the flexible serving of production lines possible for 75 % of the total base material to be processed.
Besides the open and hollow steel section products for general purpose and for steel structures, many types of steel sections for custom use are currently included in the product range in order to satisfy peculiar customer demands.
The principle of cold bent steel section production: open steel section can be produced from steel strips slit to the appropriate length by pairs of rolls assembled in stands installed behind each other, or hollow steel section can be produced by welding the two edges of the bent strip together by high-frequency induction welding.
Accordingly, the technological process of steel section production can be divided into the following phases:
- slitting: production of steel strip slit to the appropriate length from wide strip (75 % own activity, 25 % DUTRADE SSC);
- coiling: welding of the ends of steel strip coils, coiling to vertical, so-called strip accumulator to ensure continuous production (in the case of hollow steel sections);
- forming: going through 7 - 9 stands, the steel strip is given the required shape as an effect of the shaped rolls in the stands;
- high frequency welding: in the case of hollow steel section production, welding together the two edges of the bent strip by high-frequency induction welding;
- sizing: hollow steel sections are given the final shape and size on 4 - 5 stands;
- cutting: to 5 - 12 m strand length by high-speed gin-saw;
- finishing: steel section strands are bundled and given identification.