--- Heating process: raw material preparation → feeding → pushing steel → heating → steel pusher →
The continuous casting billet sent hot from the continuous casting workshop or the cold continuous casting billet hoisted by a crane is hoisted to the loading table, and then sent from the loading table to the loading roller table, and then sent to the furnace roller table via the loading roller table. The hydraulic pusher pushes the continuous casting billet into the heating furnace for heating. The heating furnace is an end-in and end-out double regenerative push steel heating furnace, which is vaporized and cooled.
The billet is heated to about 1050°C-1250°C in the heating furnace, and the billet is carried from the heating furnace to the tapping roller table by the steel supporting machine, and the primary oxide scale on the surface of the billet is removed by the high-pressure water descaling device; The steel stripping roller table returns the raw material span.
---Rough rolling process: high-pressure water descaling→rough rolling (continuous rolling with 3 stands, 5 flats and 8 stands)→
The steel billet after descaling is sent from the work roller table before the rough rolling to the rough rolling unit consisting of three vertical rolls and five two-high flat-roll mills. The roughing mill is composed of 8 rolling mills. The layout is "one vertical, two leveling, one vertical, two leveling, one vertical, one leveling", there is no looper between the stands, and it adopts micro tension rolling. In order to ensure the width accuracy of the strip steel, the vertical roll adopts hydraulic pressure and is controlled by AWC+SSC. The pressing method of the flat-roll two-roll mill is hydraulic pressing. According to the thickness of the finished strip, the rough rolling mill rolls the billet to an intermediate billet with a thickness of 28-35mm. Head-off arrangement between rough rolling and finishing rolling. A width gauge is installed at the rough rolling outlet.
In order to ensure the quality of finishing rolling, the temperature of the intermediate billet entering the finishing mill should be between 950-1050℃, and the strip with unqualified temperature shall not enter the finishing rolling. The middle roller table is equipped with a rejection device to reject unqualified middle billets to the outside of the rolling line.
---Finish rolling process: flying shear→finishing rolling (continuous rolling with 1 stand, 8 flat and 9 stands)→twist→
The qualified intermediate billet is sent to the flying shear head through the intermediate roller table. Then it is sent to the finishing mill to be rolled to the thickness of the finished strip.
The finishing mill is composed of one stand and eight flats. A descaling ring is installed after finishing rolling one stand to remove the secondary scale produced during the rough rolling and transportation process; the first two of the eight flat-roll mills It is a two-high rolling mill to increase the reduction. The last 6 flat-roll rolling mills are a four-high rolling mill to improve the strip shape and dimensional tolerances; 7 electric loop devices are installed between the stands to ensure the belt The steel is rolled with constant micro-tension; in order to ensure the dimensional accuracy of the strip steel, all the adjustment devices of the rolling mill adopt hydraulic pressing. The vertical roll is equipped with AWC+SSC control system, and the flat roll is equipped with AGC thickness control system. The exit of the finishing rolling mill is equipped with a width gauge and a thickness gauge to implement closed-loop control of the thickness and width of the strip.
The final rolling temperature of the strip is controlled between 850℃～950℃, and the maximum final rolling speed can reach 15m/s.
---Finishing process: cooling → inspection → coiling → small bundle → collection, big bundle, spray number → storage
The rolled steel strip is sent to the flat chain conveyor for cooling through the torsion guide groove, pinch roller, three-way guide plate, water-cooled guide groove (reserved for forced cooling) and oscillator.
At the exit end of the flat chain, the strip head is manually clamped and sent to the exit pinch roller, and then sent to the vertical coiler (shrink core type) through a five-roller tension leveler for coiling, and the coiling ends through the dense roller The belt tail is manually welded by the winding machine and the winding machine, and then the steel coil is collected by the steel coil transportation chain, the hydraulic tumbling machine and the steel coil collection device.
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