How To Design And Reform The Short And Small Workshop Which Is Compatible With Bar And Stainless Steel High-Speed Wire?

Projects requiring Transformation: a large bearing steel bar production line owned by a Chinese company with independent intellectual property rights, whose products are Ф 40mm and above.

Background of transformation: with the market changes and the needs of the company's own development, the company decided to build another stainless steel high-speed wire rod production line in the original plant. However, the area of the original plant is only 185mx30m, and it can no longer accommodate a high-speed production line according to the Convention.

After design and transformation, the product scheme and production scale of the new high-speed wire rod production line: the steel type is mainly austenitic stainless steel; 220mm raw material × 220mm × 3M square billet; The final rolling line speed is 75 ~ 90m / S; Product specification Ф 5．5～ Ф 16.0mm, coil weight about 1100kg; The designed annual output is 300000 t.

Technical difficulty analysis and design scheme

There are two technical difficulties in adding a wire rod production line on the basis of the original production line: first, the length of the workshop is not enough, and the rolled pieces must turn around, which is rare in the layout of high-speed production lines in the world; Second, the transition from pre finishing mill to finishing mill requires the use of a shroud, but the rolled piece is easy to be scratched and the looper stability is poor when tripping. In view of the above difficulties, it was decided to adopt the scheme of vertical arrangement of wire drawing machine and cooling roller table, as well as the scheme of adding side looper to the duct.

Finally, the stainless steel high-speed wire rod production line is divided into two parts: rolling area and finishing area. Main equipment and performance are as follows:
(1) Finishing mill: the finishing mill is Morgan's 5th generation top crossing 45 degree heavy-duty torsion free mill, with a total of 10, of which 5 are Ф 230mm rolling mill, the other 5 are Ф 170mm rolling mill. The designed rolling speed is 90m / s and the guaranteed speed is 75m / s.
(2) Reducing sizing unit: at present, the reducing sizing unit is usually provided by Morgan, Symantec and Danieli. The first two reducing and sizing units are of mechanical transmission type, driven by one motor. Danieli's reducing sizing unit is of double module type, driven by two motors. Although the mechanical equipment is simplified, it is difficult for the two motors to drive the electric control, the speed matching is not good, and the steel drawing is serious. Therefore, the reducing sizing unit is reserved temporarily.
(3) The equipment in the finishing area is mainly composed of air-cooled roller table, coil collecting station, P / F line, baler, coil scale, coil unloading station, etc. Due to the reasonable design, the operation problem of the wire rod in the vertical air-cooled line of the spinning machine is solved, and the wire rod is ensured to run regularly and stably on the delayed air-cooled roller table after leaving the spinning machine, so as to ensure the normal production in the crowded workshop.

Through careful research and design, it is feasible to be compatible with the bar production line and high-speed production line in the original short and small plant. The stainless steel high-speed wire was put into production in november2010. The design mode in this paper provides a successful example for those manufacturers who make structural adjustment without laying new plant land and saving land.