Method and device for treating a strip of fibrous material in a long nip press unit

摘要

The press arrangement comprises transferring a fibrous material web to a long nip press unit (29) through an extended press nip (26), where the long nip press unit has a press roll (24) with a rotating press jacket (25) and a mating roll (23). The fibrous material web is transferred to a transfer element in connection to the extended press nip on the press jacket of the press roll, where the transfer element receives the fibrous material web. The rotating press jacket consists of a carrier and an elastically compressible polymer coating, which is turned to the fibrous material web. The press arrangement comprises transferring a fibrous material web to a long nip press unit (29) through an extended press nip (26), where the long nip press unit has a press roll (24) with a rotating press jacket (25) and a mating roll (23). The fibrous material web is transferred to a transfer element in connection to the extended press nip on the press jacket of the press roll, where the transfer element receives the fibrous material web. The rotating press jacket consists of a carrier and an elastically compressible polymer coating, which is turned to the fibrous material web and has a hardness of 50-97 Shore-A, where the surface of the polymer coating contacting the fibrous material web has a reversible pressure-dependent roughness (R z) of 2-80 mu m in an unloaded state measured according to ISO 4287 and has a roughness (R z) of 0-20 mu m in a loaded state with a linear load of 20-600 kN/m. The rotating press jacket is impermeable. The polymer coating contains a polymer composition, and particulate filler material, which contains kaolin-clay, polymer material or stainless steel. The polymer coating completely encloses the carrier. An independent claim is included for a method for treating a fibrous material web in a paper or cardboard machine.