摘要:
The invention concerns a method and an arrangement for computing and regulation of the distribution of linear load in a multi-nip calender. The material web (W) is passed through the nips (N1...N9) in the set of rolls (12), which set of rolls comprises a variable-crown upper roll (13), a variable-crown lower roll (14) and intermediate rolls (15...22) fitted between the upper and lower rolls (13, 14). All the rolls in the set of rolls are supported so that, when the nips (N1...N9) are closed, the bending lines of the rolls are curved downwards. In the computing and regulation of linear loads, the physical properties affecting the bending of each intermediate roll (15...22) under load, such as bending rigidity, mass, shape, and material properties, are taken into account. The ratio of the linear loads applied to the intermediate rolls (15...22), the own weight of the rolls, and of the support forces applied to the rolls is regulated so that the set of rolls is in a state of equilibrium and in a predetermined state of deflection. The invention also concerns a multi-nip calender that carries out the method.
摘要:
Ein Verfahren zum Voreinstellen eines Kalanders für Papier, Pappe u.dgl. weist einen Stapel (1) aus einer Unterwalze (4), mindestens einer Mittelwalze (3) und einer Oberwalze (2) auf. Die Unterwalze ist eine Biegeeinstellwalze mit Mantelhub, die Oberwalze eine Biegeeinstellwalze ohne Mantelhub. Die internen Stützvorrichtungen (15) der Unterwalze (2) werden mit Druck derart belastet, daß der Mantel (14) der Unterwalze etwa einen Zylinder mit horizontaler Achse bildet. Zum Schließen der Nips (18, 19) werden die externen Stützvorrichtungen (13) der Unterwalze oder deren internen Stützvorrichtungen (15) mit einem ansteigenden Druck belastet. Der den jeweils anderen Stützvorrichtungen (15) der Unterwalze zugeführte Druck wird dem Träger entsprechend nachgeführt. Die im Augenblick des vollständigen Schließens des obersten Nips (18) in den externen und internen Stützvorrichtungen (11, 13, 15) wirksamen Drücke werden registriert. Ein Kalander zur Durchführung dieses Verfahrens weist im Bereich mindestens des einen Endes des obersten Nips (18) eine Meßvorrichtung (20, 21) auf, die beim Schließen dieses Nipendes ein Schließsignal (S) abgibt. Auf diese Weise ergibt sich eine sehr einfache Kalibrierung.
摘要:
The invention concerns a calender for calendering of a paper or of an equivalent web material. The calender comprises a frame (11; 11a), a variable-crown upper roll (13; 13a), a variable-crown lower roll (14; 14a), and two or more intermediate rolls (15...22; 15a...22a) fitted between the upper (13a; 13a) and lower (14; 14a) rolls, said upper, lower and intermediate rolls being arranged on the frame (11; 11a) of the calender as a stack of rolls (12; 12a) and being in nip contact with one another to form calendering nips (N 1 ...N 9 ) between said rolls. At least one of the intermediate rolls (15...22; 15a...22a) is a cooled roll, which is provided with a resilient polymer coating and with bores or equivalent ducts formed in the body of said roll for circulation of a cooling medium.
摘要:
Method and equipment for regulating an extended press treatment nip (N p ). By means of the method, the transverse treatment-pressure distribution of the material web (W) passing through the nip (N p ) is controlled by using a series of power members. In the method a regulating system (100, 200, 300, 400) is used, by means of which the effective powers of the power members are regulated separately. Further, a mathematical model illustrating the nip (N p ) to be regulated and the web (W) to be treated is created. A set value distribution Q(Z) of the pressure profile of the nip is determined, wherein Z = 1....N and (N) is chosen as substantially larger than the number (K) of the separately adjustable power members or power member groups. On the basis of the mathematical model, a zone conversion block (120) is programmed, whose input quantities consist of set line pressures (Q₁...Q N ) and whose output quantities consist of zone-pressure set values (P₁...P K ). The zone conversion is programmed so that such a linear-load profile of the material web (W) can be accomplished whose deviations from the set value profile Q(Z) are minimized. The converted zone-pressure set values (P₁...P K ) are passed into an intelligent regulating unit (300) provided with diagnostic and protection so as to constitute set values (B) for zone pressures. Each of the power members or power member groups of the nip (N p ) to be regulated is regulated separately by means of the set values (B).
摘要:
The invention relates to a sealing strip (1) for a sealing device for sealing off a positive or negative pressure zone of a suction or blowing roller of a machine which processes and/or produces web materials, particularly a paper, paperboard or tissue machine, said sealing strip (1) having a sealing surface that can be placed, for the purpose of sealing the positive or negative pressure zone, against the inner side (3) of a roller sheath (4) and that comes into frictional contact therewith when the roller sheath (4) is rotated, said sealing strip (1) comprising a lubricant channel (5) which is formed from a cut-out from the sealing strip, is open towards the inner side of the roller sheath, comprises a front and a rear wall (6, 7), and by means of which lubricant can be brought into the intake gap between the sealing surface (2) and the inner side (3) of the roller sheath. When viewed in the rotational movement direction (D) of the roller sheath (4), the lubricant channel (5) is arranged in front of the sealing surface (2), and the front wall (6) is arranged in front of the rear wall (7). The sealing strip (1) comprises a first material section which forms at least the sealing surface (2) and consists of a first material, and a second material section at least some sections of which form at least the front wall (6) and which consists of a second material, said first and second materials differing from one another in terms of at least one physical property such as, for example, elasticity modulus, abrasion resistance, hardness, or brittleness.
摘要:
The invention relates to a roller (1) for use in paper machines, having a roller core (11), a roller covering (12) surrounding the roller core (11) and at least one optical waveguide (21) having a plurality of fibre Bragg gratings (22). The at least one optical waveguide (21) is either arranged between the roller core (11) and the roller covering (12) or embedded in the roller covering (12). Sections of the at least one optical waveguide (21) which each contain a fibre Bragg grating (22) alternate with sections of the at least one optical waveguide (21) which are free of fibre Bragg gratings (22) in the longitudinal direction of the optical waveguide. Sections of the at least one optical waveguide (21) which each contain a fibre Bragg grating (22) also enclose an angle with a circumferential direction to the roller (1) of less than 80° and in particular less than 60° and further in particular less than 45°.