Double fourdrinier assembly, to convert a fiber pulp into a wet paper/cardboard web, has suction units to extract water on both sides of the fourdrinier with opposing bars with adjustments

摘要

The double fourdrinier assembly to convert a fiber pulp from a stock inlet (1) jet (2) into a wet web, for paper or cardboard, has at least two continuous fourdriniers (3,4) and water extraction units (7,8) on opposite sides of the fourdriniers. The water extraction units have curved surfaces, to conform to the surfaces of the fourdriniers. The suction surfaces can be concave or convex, with a curvature radius of 1-10 m. The suction units are divided into zones (Z1-Z3) working at pressures or vacuums of 1-30 kPa and especially 3-10 kPa. The suction units have opposite bars (11-16), with adjustable settings between them.