Abstract: The moisture profile and/or moisture gradient of a paper web of at least SC quality paper is controlled in a paper machine comprising a calender (1) which has at least two roll stacks (21, 22; 31, 32), one stack has at least three rolls and another has at least five rolls. The web is moisturized to a desired pre-moisture content M1 by a pre-moisturizer (7) before the calender. At least one intermediate moisturizer (3) is arranged between two roll stacks moisturizes the web to a desired intermediate moisture content M2 before the last roll stack (31, 32), in which the web is dried to a desired final moisture value M3. For continuously controlling and optimizing the moisture profile and/or moisture gradient of the web, the pre-moisturizing W1 of the web is controlled by a pre-moisturizer (7) control parameter which corresponds to the final moisture value M3 of the web.

Abstract: A system for maintaining calender rolls of a paper machine clean when producing high-gloss paper or coated paper, such as LWC or MWC. To prevent a coating agent, such as coating dye, from adhering onto and soiling a smooth surface of a calender roll, with an overheating phenomenon, the system has a second measurement station (10) provided with measuring and indicator means for producing an output indicating soiledness of the web (W) or a humidity profile. When the output of the second measurement station (10) indicates excessive soiledness or an uneven humidity profile, the system performs at least one of: cleaning the surface of the smooth-surfaced calender roll; changing the nip load in the calender (5); making a correction adjustment of the CD-directional humidity profile of the web (W); cutting the web (W) and conducting it into the pulper; and/or changing the running speed of the web (W).

Abstract: The moisture profile and/or moisture gradient of a paper web of at least SC quality paper is controlled in a paper machine comprising a calender (1) which has at least two roll stacks (21, 22; 31, 32), one stack has at least three rolls and another has at least five rolls. The web is moisturized to a desired pre-moisture content M1 by a pre-moisturizer (7) before the calender. At least one intermediate moisturizer (3) is arranged between two roll stacks moisturizes the web to a desired intermediate moisture content M2 before the last roll stack (31, 32), in which the web is dried to a desired final moisture value M3. For continuously controlling and optimizing the moisture profile and/or moisture gradient of the web, the pre-moisturizing W1 of the web is controlled by a pre-moisturizer (7) control parameter which corresponds to the final moisture value M3 of the web.

Abstract: A soft calender has a body structure (10) and at least two roller sets (11; 12). There is at least one calendering nip (N1, N2, N3, N4) formed in between two rollers (13, 14; 14, 15; 16, 17; 17, 18). Of the rollers forming the nip, at least one is a roller with a soft surface (13, 15; 16, 18) and the other is a heating roller (14, 17). The calender body structure (10) is formed with a stepped shape in such a way that the roller sets (11, 12) can be located in an upper and a lower place of location (21) on the same side of the body.

Abstract: A soft calender has a body structure (10) and at least two roller sets (11; 12). There is at least one calendering nip (N1, N2, N3, N4) formed in between two rollers (13, 14; 14, 15; 16, 17; 17, 18). Of the rollers forming the nip, at least one is a roller with a soft surface (13, 15; 16, 18) and the other is a heating roller (14, 17). The calender body structure (10) is formed with a stepped shape in such a way that the roller sets (11, 12) can be located in an upper and a lower place of location (21) on the same side of the body.

Abstract: A system for maintaining calender rolls of a paper machine clean when producing high-gloss paper or coated paper, such as LWC or MWC. To prevent a coating agent, such as coating dye, from adhering onto and soiling a smooth surface of a calender roll, with an overheating phenomenon, the system has a second measurement station (10) provided with measuring and indicator means for producing an output indicating soiledness of the web (W) or a humidity profile. When the output of the second measurement station (10) indicates excessive soiledness or an uneven humidity profile, the system performs at least one of: cleaning the surface of the smooth-surfaced calender roll; changing the nip load in the calender (5); making a correction adjustment of the CD-directional humidity profile of the web (W); cutting the web (W) and conducting it into the pulper; and/or changing the running speed of the web (W).

Abstract: A roll for use in the manufacture of paper and board, a press roll, in particular a center roll in a press, a backup roll for an extended-nip press roll, a hot press roll, or equivalent, which is in direct contact with a wet paper web, or a calender roll, a method for manufacturing the same and a coating composition therefor including an adhesion layer arranged on the frame part of the roll and a ceramic layer arranged on the adhesion layer. The ceramic layer has a thickness of from about 100 &mgr;m to about 2000 &mgr;m and includes from about 50% to about 95% by weight of Cr2O3 and from about 3% to about 50% by weight of TiO2, or from about 50% to about 80% by weight of Al2O3 and from about 20% to about 50% by weight of ZrO2, or exclusively Al2TiO5. The outer face of the ceramic layer is finished until the roughness Ra is from about 0.2 &mgr;m to about 2.0 &mgr;m and/or the porosity of the outer face of the roll is from about 1% to about 20%.

Abstract: A threading device and a method for threading a tail of a web, wherein, for guiding the path of a tail separated from a full-width web in a paper machine or a paper finishing device, the threading device comprises a suction channel, placed at least partly in a paper machine portion and provided with a reduced pressure for gripping the tail, and transfer means for transferring the suction channel in the portion of the paper machine and simultaneously for releasing the tail to the portion.

Abstract: A roll for use in the manufacture of paper and board, a press roll, in particular a center roll in a press, a backup roll for an extended-nip press roll, a hot press roll, or equivalent, which is in direct contact with a wet paper web, or a calender roll, a method for manufacturing the same and a coating composition therefor including an adhesion layer arranged on the frame part of the roll and a ceramic layer arranged on the adhesion layer. The ceramic layer has a thickness of from about 100 &mgr;m to about 2000 &mgr;m and includes from about 50% to about 95% by weight of Cr2O3 and from about 3% to about 50% by weight of TiO2, or from about 50% to about 80% by weight of Al2O3 and from about 20% to about 50% by weight of ZrO2, or exclusively Al2TiO5. The outer face of the ceramic layer is finished until the roughness Ra is from about 0.2 &mgr;m to about 2.0 &mgr;m and/or the porosity of the outer face of the roll is from about 1% to about 20%.

Abstract: A method and apparatus for producing calendered paper by an on-line manufacturing system comprising at least a paper machine and a multi-nip calender. The method comprises following steps: removing water from a formed paper web by pressing, drying the pressed paper web by at least one dryer, calendering the dried web by the multi-nip calender, measuring a cross-machine moisture profile or a variable relative thereto, and altering the moisture of the web so that the moisture profile of the web in the cross-direction is even when the web enters the first nip of the calender.

Abstract: In the method for paper web transfer in a paper machine or finishing apparatus for paper, a paper web (W) is transferred in a first machine portion (A) at a first travelling speed. In a second machine portion (B) following the first one in the travel direction of the web, the tail is transferred at a travelling speed lower than the first travelling speed. In the second machine portion (B) the tail (TB) is transferred independently without a draw connection to the web (W, TA) transferred in the first machine portion (A), the travelling speed of the tail (TA) transferred in the second machine portion (B) is increased, and a draw connection is established between the tail and the web (W, TA) transferred in the first machine portion.

Abstract: A paper machine roll, in particular for a soft calender or supercalender, which includes a metal frame, roll ends, and shafts. The frame is coated with a polymer coating over at least a middle area or central region thereof while lateral regions may optionally remain uncoated. In order to equalize a difference in temperature between the roll ends and the optionally non-coated lateral regions of the metal frame, on one hand, and the coated central region area of the roll, on the other hand, an arrangement for equalizing the difference in temperature is provided by heating the roll ends and the optionally non-coated lateral regions of the metal frame.

Abstract: A paper web is passed through a calendering nip that is formed between a roll which has been provided with a soft face and a heatable hard roll. The heatable roll is heated so as to plasticize the surface layer of the paper web that is placed at the side of the heatable roll, preferably so that the temperature of the surface layer in the calendering nip exceeds the glass-transition temperatures of the polymers contained in the paper. Before entering into the calendering nip, the paper web is moistened, so as to lower the glass-transition temperatures of the polymers contained in the paper, and pre-heated. The pre-heating of the paper web is carried out by bringing the paper web into contact with the heatable roll before the web enters the calendering nip and by, before the calendering nip, feeding steam or water onto the face of the paper web that is placed at the side of the heatable roll so as to improve the transfer of heat from the hot roll to the paper web.

Abstract: A supercalender comprises a stationary variable-crown upper roll (1), a floating variable-crown lower roll (2), several intermediate rolls (3,4) between the upper roll (1) and the lower roll (2), and a hydraulic control system. The upper roll (1) has a roll mantle (12) that is supported on the roll shaft (11) by hydrostatic loading elements (13) acting in the direction of compression and by end bearings at the ends of the roll mantle, which bearings prevent displacement of the mantle (12) ends in the radial direction relative to the shaft (11) of the upper roll. The lower roll (2) has a roll mantle (22) that is supported on the roll shaft (21) adjustably in the direction of compression by means of hydrostatic loading elements (23). Position detectors (23,31) are provided at the ends of the shaft of at least one roll.

Abstract: The present invention relates to a continuously running rewinder with a pressure roller for winding a paper web, for instance, from a supercalender onto a reel-up drum. The rewinder comprises roll stands, which are provided with a primary drive for rotating a rewinding reel-up drum, a pressure roller assembly including the pressure roller via which the web is routed to pass before entering the rewinding reel-up drum and which can be actuated to swing from an open position to a closed position toward the roll stands so that the pressure roller assembly is pressed against the rewinding reel-up drum to form with it a nip for the web. The rewinder includes a pressing bar, whose path of movement is adapted to pass between the pressure roller and the rewinding reel-up drum and via which the web is routed to pass so that when the bar is in its lower position and the pressure roller assembly in its open position the bar holds the web at a lower level than that of the nip.

Abstract: A control device in particular in a multi-roll press (22 to 24) of a calender intended for the glazing of a continuous thin web, such as a paper web, which said press comprises a compensated upper roll (22), a compensated lower roll (24), and at least one press roll (23) fitted between the rolls. The control device itself comprises a press-load control circuit (B, C, D, 11, 14, 15; A, 29, 30), a compensation circuit (E, 16, 17) for the upper roll (22), as well as a compensation circuit (F, 27, 28) for the lower roll (24). According to the invention, both of the compensated circuits (E, 16, 17 and F, 27, 28) are, via their own feedbacks (12 and 13), connected to the control circuit (B), which is fitted so as to select the most slowly changing one from among the signals of the feedbacks (12 and 13) and to brake down the roll (22 or 24) whose compensation is being varied most rapidly.

Abstract: A roll comprises a rotatable mantle portion and a non-rotating shaft portion and, connected to the shaft portion, means for roll deflection adjustment. These means comprise a bushing or the like mounted around the non-rotating shaft portion at one roll end and being, by means of a bearing, in radially force transmitting contact with the roll mantle portion. The bushing is pivotably connected to the shaft portion at a position between the bearing and a second bearing between the shaft portion and the mantle portion at a position more remote from the roll end. The bushing is provided with a device for altering radially the position of the first mentioned bearing with respect to the shaft portion by altering the angle setting of the bushing with respect to the roll shaft portion.