1500mm Continuous Galvanizing Line
1.Design basis
Raw material: Pickling hot rolled strip,cold rolled carbon structure
steel, high quality carbon structure steel and low alloy steel coil should
match standard: GB708-88: Dimension, figuration, weight and allowed
deviation of cold rolled sheets/strips and GB13237-91: Quality carbon
structural steel cold rolled thick sheets/strips
2.Production capacity: 250thousand MT/year
3.Annual time: 8760h
4.Annual heavy maintenance time: 720h(30×24h)
5.Annual fixed maintenance time: 480h (4times×5days×24h)
6.Annual rated working time: 7560h(8760-720-480)
7.Stopping time: 390h
8.Annual effective working time: 7170h (calculation according to product percentage)
9.Process method: NOF method
10.Products process: Hot dip galvanizing
11.Execute criterion of product quality: GB2518-2004
12.The process layout:
Saddles→Coil Car→Payoff Reel→Pinch Roll→Shear→Seam Welder→Bridle roll→Entry loop→Bridle roll→Degreasing section→Hot Air Dryer→Steering Unit→Bridle roll→Tension Measure→Annealing Furnace→Furnace Bridle→Zinc Pot→Sink Rollers→Air Knife→Cooling tower→Tower Turning Rolls→Air Cooling Unit→Quench Tank→Hot Air Dryer→Steering Unit→Bridle roll→Skin Pass Mill→Bridle roll→Tension Leveller→Bridle roll→ Passivation Coater→Dryer Oven→Exit loop→Bridle roll→Electrostatic Oiler→Shear→Pinch Roll→Recoiler→Coil Car→Saddles
Annealing furnace is adopt the NOF processing, which is mixed by direct fire and gas radiant tube, horizontal structure. This design brings advantages of good annealing quality, no pollution in the furnace, threading and easy to maintain.
Power cooling is equipped to improve the ability of temperature lowering.
Ceramic zinc pot is heated by power frequency inductors to increase the melting ability and temperature adjusting ability.
The cooling tower is equipped with 5 sets of air coolers for lowering the temperature of Galvanized strip steel rapidly.