Head Box, Wire and Press Section - Process Info
Head Box, Wire and Press Section - Introduction and background
From the primary machine screen diluted stock is fed to the paper machine head box which normally has a control dilution system. The head box jet is diluted to a nip between the top and bottom wires. The paper web is dewatered and formed between the two wires. Dewatering takes place through both wires and the white water is collected and led to the wire silo. The wires are cleaned with shower pipes supplied with different pressures.
The press section with a number of press nips consists mainly of press rolls, felts and felt rolls. The first roll is called the pick-up roll. It picks up the web from the wire section and transfers it into the press sections where dewatering takes place in the nips. To collect water from the press section there are trays which lead the water to the tray water chest. The pressure in the press nips is accomplished by hydraulic cylinders.