Duplex Board Paper Cardboard Paper Coating Board Paper Making Machine

1. The duplex board paper basis weight is 200-350gsm,it is heavier than other kind of paper, and the front color is white and back color is gray usually,so paper pulp is generally divided into surface layer, two layers, three layers, and four layers;

2.The first layer is top layer pulp, which requires high whiteness certain strength,which usually use bleached sulfate wood pulp;

3.The second layer is the lining layer, which plays the role of separating the surface layer and the core layer. It also requires certain whiteness, usually use 100% mechanical wood pulp or light-colored waste paper pulp.;

4.The third layer is the core layer, which is mainly used for filling to increase the thickness and stiffness of duplex board. usually use mixed waste paper pulp;

5.The last layer is the bottom layer, which has the functions of improving the appearance, strength and preventing curling of the duplex board. usually made from better waste paper pulp.

Paper machine main structure

1. Headbox : Two sets of open headbox, corresponding to top layer, bottom layer, and by controlling the gas pressure in the headbox to control and stabilize the sizing of the pulp.

2. Forming section : Double layer include top layer and bottom layer, The main components are consist of breast roll , forming board, dewatering board, vacuum box, composite roll, suction couch roll, wire drive roll, wire guiding roll and paper machine framework.Top layer and bottom layer are all equipped with one forming wire respectively .

3. Press section: including First press, second press.The first press is K-type composite press with vacuum suction roll, which also equipped with one rubber coated metal roller, one vacuum press roll and one stone roll.The second press is MG press with upper & lower rubber coated metal rolls and upper & lower felts. The two press are all equipped with wire guiding roll and felt suctionbox. These two press are pressurized by the hydraulic cylinder pressure.

4. Front drying section: Φ1500/Φ1800 dryer, drove in group and equipped with wire guiding roll , dry wire and closed gas hood.

5. Oblique surface sizing machine: one surface chrome-plated metal roller and one rubber coated metal roll. it is pressurized by corrugated gas tire pressure.

6. Back drying section: Φ1500/Φ1800 dryer drove by group and equipped with wire guiding roll ,dry wire and closed gas hood.

7. Calender section: Double roller calender, the upper and lower rollers are metal rollers, pressurized wayis the corrugated gas tire pressure.

8. Reeling section: Pneumatic horizontal reel and pressurized way is cylinder pressure.