DFT (Direct Forming Technology) is an innovative technology used in pipe mill manufacturing. Compared with traditional forming method where the steel strip goes through a series of forming rolls to form a circular shape before shaping to square or rectangular profiles, the steel strip that is fed into a direct forming mill is bent into the shape of the SHS and RHS directly before welding. For a direct forming mill, one set of rolls cover complete range of sizes. Any size can be set in 20 minutes with the help of Servo motors & planetary gearboxes, significantly saving the tooling cost and reducing roll adjustment time.

The break down section incorporating driven roll stands (universal stands) and side roll stands is designed for continuous forming of steel strip into square and rectangular shape. Spherical roller bearings are adopted for self-aligning. The fin pass section is designed with alternating upper rolls and side rolls with the addition of support rolls, making it possible to use one set of rolls to produce tubes with all specifications.

This sizing section is composed of a gantry type stand, permitting roll adjustment for all sizes of tubes without changing a single roll. The whole mill adopts PLC control system. The forming and sizing rollers are motor adjustment driven by servo motor and PLC control, easy to operate and maintain.

The final products manufactured out of the direct forming mill have significantly less scratches and surface defects in comparison with that of the traditional tube mills due to the evenly distributed force exerted on the strip surface by the rolls during the production of the direct forming mill. In addition, thanks to certain bending & deforming characteristics, the direct forming mills naturally consume much less energy during production.

Value Highlights

• Great flexibility and possibility of modifying the tube dimension without removing shafts and stands and any roll change for any size included in the mill size range
• Utmost to save time and cost for rollers
• Power consumption is decreasing significantly due to lower motors voltage
• Display with automatic illustration of tube section for each production step
• Easy use of software for setting up of any production parameter, including tube angle radius
• Reduction of manpower thanks to the complete automation of the mill operation and adjustment
• Easy access and retrieving adjustment recipes, one click after pulling out the recipe to complete the roll adjustment
• Featured with capability of individual and compound drive of forming and sizing mills, the corresponding drive mode can be chosen according to the actual needs on site  
• Highly automated roll adjustment, enabling a shortened time of 15-20 minutes for size changes of small-to-medium difference, of 30-40 minutes for the ones of large difference, resulting in great reduction of workload

Technical Data Sheet