The use of polyurethane rubber rollers in the paper industry
A large number of rubber rollers are used in Fourdrinier paper machines and circular paper machines used in the paper industry. Different parts of the paper machine are equipped with rubber rollers for different purposes. A large Fourdrinier machine needs more than 70 rubber rollers.
A volt roller is installed on the wire part of the paper machine, and the hardness of its rubber layer is preferably controlled at 30-35 Shore A. Too high hardness will cause poor contact between the flat roller and the garden net, affect the wet paper sheet to lift off the net, and also produce pressure stains. If the hardness of the rubber layer of the flat roller is too low, the squeezing effect on the wet paper is small, resulting in the disadvantage of high moisture in the wet paper.
The press part of the paper machine is equipped with a dehydration press roll, a vacuum press roll, a groove press roll, a net press roll, a guide blanket roll, and a tight blanket roll. The dewatering press roll is the most important rubber roll on the paper machine, and its main purpose is to remove moisture from the wet pulp. The hardness of the press roll is usually 80-90 Shao A degrees, and the highest hardness is above 98 Shao A degrees. It is a quartz rubber roller made of quartz sand in the rubber. The hardness of the press roll is increased correspondingly with the continuous increase of the pressure of each press line. During operation, the squeezing dewatering rubber roller will produce certain deformation or bending. In order to make the pressure on the pulp uniform, the rubber layer at the bend must produce certain flexure and creep.