500000Ton Push-pull Acid Pickling Production line /Push-pull type

This structure can avoid neoprene lined to break when the granite stone is replaced. Between each tank section there is acid liquid squeezing Roll and acid liquid isolation room, at bottom the land with granite stone lined is at the same horizontal level with the down roll of the squeezing rubber roll. On the coil running platform there is one granite stone cover. Squeezing roll is driven by frequency conversion, and during threading process the coil end position status can be detected through motor currency variation, which shall help avoid that the thinner coils being overlapped inside the acid tank avoided. In each acid tank one acid liquid circling heating system is set, the system adopts vertical graphite heat exchanger, on top of coils there is PPH covers. At the same time the acid liquid shall move fast in turbulence form under the functions of tank wall structure, thus speed for acid pickling is increased. New acid will be continuously added at constant volume from 5# acid liquid circling tank, meanwhile be gradually filled into 3#, 2#, 1# tanks successively via acid liquid circling tank liquid level controlling system, finally be piped into waste acid liquid collection tanks from the 1# tank.

Due to the relative isolation among each acid liquid tank and their independent circling, the acid concentration difference of each tank could be effectively controlled. Pre-rinsing section will rinse the coils independently, in water spraying section condensation water circled spraying shall be adopted, clean water shall be added from 5th level rinsing tank. The rinsing water in water collection box at bottom of rinsing tank shall flow to the 1st level from the 5th level, then be discharged into rinsing water collecting tank from 2nd level overflow port. The whole acid pickling tank and rinsing water tank are controlled by minus pressure.

The acid mist is collected centrally and sent to the acid mist washing tower through the exhaust pipe set at the inlet and outlet of each section. After cooling spray washing, the factory exhaust is vented out. The exhaust emissions are about 22000m3/h., among which there is less than 20mg/m3 of hydrogen chloride. Coils are dried by hot wind dryer and hot wind heating use vapor heat exchanger. Coil trimming cutting is done by cantilever type circle shearer, one pinch CPC is set at the entrance of the circle shear to control the centering during the trimming shearing, and the waste trimming cut will be coiled to be waste trimming ball by the waste coiler.

Reserve the electrostatic oiler before the strip coiling to prevent the strip from rusting and increase the storage time of the strip. The coiler is cantilevel type tensional strength coiler, the coiling tensional strength is setup through 3-roll driven tensioner, and EPC is set to control the trimming coiling for a uniform edge. In exit uncoiling section unloading car driven by hydraulic shall transport the coils to unloading table. The electric control system is constituted by power distribution system, ac frequency conversion motor transmission device, ac frequency conversion motor controlling unit, PLC operation control system, general operation platform, individual operation platform and uncoiling industrial monitoring system. System operation control is completed by PLC programmable controller, the operation system also includes the chain controlling function from the auxiliary process system of the acid pickling unit.