Paper Manufacturing

Paper Machine Composite Roll Covers

6.2.4.3.3 Composite Roll Covers Two basic composite designs for the functional layer of roll covers are used in the paper industry: Composite covers with a fiber reinforced functional layer and com¬posite covers with a cast functional layer (resin covers). 6.2.4.3.3.1 Fiber Reinforced Functional Layer Composite covers with fiber reinforcement in the functional layers are...
Read More »

Paper Machine Polyurethane Roll Covers

6.2.4.3.2 Polyurethane Roll Covers Polyurethane roll covers were introduced to the paper industry at the end of the 1980s. The outstanding mechanical and dynamical properties make polyurethane the most suitable material for soft elastomeric covers in press positions. Depend¬ing on paper quality and press design, high open surfaces up to 45 % with grooves,...
Read More »

Paper Machine Rubber Roll Covers

6.2.4.3.1 Rubber Roll Covers Rubber roll covers are the covers with the longest tradition. The hardness ranges from very soft elastomeric covers to hard rubber. Both natural rubber and synthetic rubber polymers are used. Typical rubber formulations consist of approximately 8 to 15 ingredients, such as polymers, fillers, processing materials, tackifiers, anti¬degradant components, colorants,...
Read More »

Rolls in Paper and Board Machines : Nip Design in Calenders

6.2.4.2.5 Nip Design in Calenders The functions of covers or coatings in soft nip calenders are twofold. The hard heated roll in the calender is either a chilled iron roll with a hard wear-resistant surface, or it is coated for even more improved wear resistance. The surface of the hard roll needs to be...
Read More »

Paper Machine Rolls: Nip Design in Coating and Sizing

6.2.4.2.4 Nip Design in Coating and Sizing For coating, sizing or pigmenting in film transfer presses the primary purpose of the cover is both to provide a soft nip and to transfer the applied liquid film uniformly to the paper web. Abrasion resistance is important for keeping the nip geometry constant, as the film...
Read More »

paper questions
paper questions


Paper Production

Buy Papermaking Books from amazon.com

Donate

Please donate with PayPal if you find this site helpful

paper questions