Abstract: An apparatus for removing dust released, for instance, during the production of a soft crepe paper web which is creped off a Yankee cylinder and spread laterally. The apparatus comprises a dust suction box consisting of a housing with an inner suction chamber, said housing having a first inlet in the form of a suction gap, a main part and first and second parts which define said suction gap between them. According to the invention the main part is in the form of part of a cylinder to provide a corresponding curved inner side in the suction chamber, and the suction gap comprises an outer gradual throttling and an inner gradual enlargement, said throttling and enlargement merging at a transition where said throttling is maximal.

Abstract: A reel-up in which paper is reeled up on reeling drums to form paper reels, said reel-up comprising two stand members each having a stand rail to support the reeling drum; a surface winding mechanism over which the web runs; and a secondary system with at least one secondary unit for receipt of a reeling drum, wherein the secondary unit comprises first and second secondary bodies which are linearly movably journalled in said stand members. According to the invention each secondary body comprises a lifting mechanism for lifting the reeling drum from the stand rail to a production level in which the reeling drum is free from the stand rails and the load of the paper reel and the reeling drum is taken up by the secondary bodies and transferred to the stand members.

Abstract: When drying a paper web (4) in a dryer section (1) of a paper machine provided with drying cylinders (2, 3) and drying wires (5, 6), shrinkage of the paper web in cross direction is counteracted by applying forces at its edge portions (11). According to the invention partial vacuum is maintained along the edge portions of the web within substantially the entire free draw (10) and is applied from the side of the drying wire (5, 6) facing away from the web (4) so that the web is sucked firmly against the drying wire by forces greater than the contracting forces acting in cross direction, thereby counteracting shrinking, said partial vacuum being set within the interval 0.1-0.8 bar, preferably 0.2-0.5 bar.

Abstract: An arrangement for feeding stock to a headbox in a papermaking machine which comprises at least one stock header with an inlet for receiving stock into the header and a plurality of stock header outlets permitting stock to leave the header. For each stock header outlet there is a stock conduit downstream of the stock header outlet permitting stock to pass from the stock header outlet, through the conduit to the inlet of the headbox. The arrangement includes a dilution header for feeding a diluent such as water to a plurality of stock conduits. The dilution header has an inlet for receiving a diluent into the dilution header and a plurality of outlets permitting the diluent to leave the dilution header. For each dilution header outlet, there is a diluent conduit permitting the passage of a diluent from the dilution header into a stock conduit.

Abstract: An apparatus and method for winding tissue webs into a parent roll includes a rotatable reel drum having a flexible outer shell for engaging a web of tissue paper against a reel spool. A deflection sensor is mounted adjacent to the inner surface of the outer shell for measuring the amount of deflection of the flexible outer shell caused by the paper roll. The amount of deflection is related to the pressure at the nip point and, by moving the reel spool and flexible reel drum away from each other as the diameter of the paper roll increases, the pressure can be controlled at a desired level. Accordingly, a predetermined light nip pressure can be applied to the roll as the tissue web is wound thereon and large parent rolls of high bulk tissue can be manufactured with desired properties when unwound.

Abstract: A reel-up in which paper is reeled up on reeling drums to form paper reels, said reel-up having two parallel stand members; a surface winding mechanism in the form of a rotating surface winding drum and/or a belt to carry the web and deliver it to one of said reeling drums or a paper reel formed or being formed thereon; and a secondary system including first and second secondary units for alternate receipt of new reeling drums. Each secondary unit, includes an outer first secondary member and an inner second secondary member, each of the secondary members having a linearly movable secondary body, an actuator for moving the secondary body, and a press device to maintain a predetermined linear pressure in the nip between the surface winding means and the paper reel as it increases in size.

Abstract: The invention relates to a scanning device (1) for measuring physical properties of a moving fibrous web (2) which has two longitudinal edges and is intended to run in a predetermined path of movement past or through the scanning device (1). The device (1) has a carriage (11) carrying a scanning head (14). The carriage (11) is movably supported for movement transversely to the direction of movement of the web (2). A drive (12) is provided which imparts to the carriage (11) a reciprocating movement from one edge side of the web (2) to the other, during which the scanning of the web (2) is carried out. The scanning device (1) is fitted with means (21, 31, 32, 33, 36) associated with the carriage for providing, in essentially the same plane as the predetermined path of movement of the web (f), a planar web supporting surface at locations between the carriage (11) and the two longitudinal edges of the web (2) during passage of the web (2) past the scanning device (1).

Abstract: To accomplish a web transfer, which in reliability is comparable to the one obtained with a closed draw, in any operating environment, but especially where it is desirable to transfer a fast running tissue web (4) from the drying section of a tissue machine, e.g., a Yankee dryer (2), to a reel-up (3), a web support device (10) extends across the width of the web (4) and along a predetermined run of the web (4) from the Yankee dryer (2) to the reel-up (3). The web support device has a support surface (11) formed by a series of plate member assemblies (23) having means for creating a flow of air in the direction of the web run. Between the web (4) and the support surface (11) the flow of air forms an air layer (15) of reduced static pressure, so as to stabilize the web (4) against flutter. The predetermined run may extend through a calender (7) and past scanner equipment (8). Pneumatic tail threading capabilities may be included.

Abstract: A top roll lifting arrangement for a roll press in a press section of a papermaking or boardmaking machine where the roll press includes a top roll and a bottom roll, the rolls being opposed and parallel and having main axes defining a press plane and forming between them a press nip. The press has a framework including two side frames in parallel relationship to each other, one located on the drive side of the machine and the other one on the tender side of the machine. Each side frame has a first vertical column upstream of the press nip and a second vertical column downstream of the press nip. The upper roll is carried by a brackets extending between the upstream and downstream vertical columns. The brackets have bevelled ends that co-operate with inclined surfaces of plate members on the vertical columns.

Abstract: A tissue web (W), which has improved formation and improved tensile properties but no appreciable deterioration of retention and layer purity, if applicable, in comparison with tissue webs produced in conventional twin wire tissue formers, may be formed in a roll type twin wire former by draining 90-99%, preferably 98-99%, of all drainable water from the slurry while on the forming roll (1), preferably a suction forming roll, the remaining 1-10%, preferably 1-2%, of the drainable water being sufficient to have a substantial amount of the papermaking fibers free in the slurry during an initial phase of a subsequent step, and, downstream of said forming roll (1), draining said remaining 1-10%, preferably 1-2%, from the slurry while vibrating the slurry sufficiently to create a micro-turbulence causing a small scale agitation of the fibers to prevent them from forming any appreciable fibrous web (W) on the two forming fabrics (3; 4) until the water remaining in the slurry is insufficient for allowing the fibers

Abstract: In a compact frame assembly for a press having a top roll (5) and a bottom roll (4), the ends of which are supported in bearing housing members, each bearing housing member (16) for the bottom roll (4) has a head portion (53) of substantially T-shaped cross section, and each bearing housing member (17) for the top roll (5) has a foot portion (54) of inverted substantially T-shaped cross section. The foot portion stands on the head portion, and two sturdy channel bars (34, 35) are pivotally mounted laterally of the head portion and the foot portion, one on each side. The channel bars may be swung into clamping engagement with the cross bars (55) of the two tees to connect the head portion (53) to the foot portion (54).

Abstract: A three-layer headbox has two rigid separator vanes (11; 12) mounted in the headbox slice chamber (10) to form two outer stock flow channels (39; 41) and an intermediary one (40). The upstream end of each vane (11; 12) is securely fixed in cantilever fashion and its downstream end (15; 16) is unattached and free and provided with a vane extension (17; 18). Also the downstream end (20; 22) of the extension (17; 18) is unattached and free and is located just downstream of the slice opening (14). The vane extension (17; 18) is thinner than the vane (11; 12), so that a step (23, 24) is formed on each side of the vane (11; 12) and extension (17; 18) assembly. To improve the layer formation, each vane (11; 12) and each vane extension (17; 18) has a portion located in a converging downstream portion (13) of the slice chamber (10), and the vane portions and the extension portions are of substantially equal length.

Abstract: A creping doctor apparatus includes a creping doctor (4) having a doctor blade (5) with a working edge (6). The creping doctor (4) is pivotable around a rotational axis (12) formed substantially at the working edge (6) to permit adjustment of an impact angle (A) formed at the working edge (6) between an impact surface of the blade edge and the cylindrical surface (2) of a Yankee dryer (3), from which an adhering paper web (1) is to be creped off. The impact angle (A) controls the result of the creping operation, e.g. the caliper and/or the macrostructure of the soft crepe paper web produced, but wear of the working edge (6) gradually causes a change in the impact angle (A) and, thereby, in the creping conditions. To maintain the desired caliper and/or the desired macrostructure as far as possible it is necessary to compensate for the wear of the working edge (6) by pivoting the creping doctor (4) substantially around the working edge (6) so as to maintain the impact angle (A).

Abstract: In a known method of rebuilding a conventional tissue machine having a conventional C-wrap type twin wire forming section to a TAD machine, a TAD section, which includes a looped TAD fabric (24) and at least one TAD cylinder (22) located inside of the TAD fabric loop for thermally predrying the formed paper web (13) by passing hot air through the web, is incorporated in the machine.

Abstract: The reel-up has a surface winding drum; two rails to support the reeling drum over which the web runs; secondary carriages movable linearly along the rails and provided with press devices to press against the reeling drum to maintain a linear pressure between the surface winding drum and the paper reel as it increases in size; and drive motor for central driving of the reeling drum. The central drive motor is mounted to one of the secondary carriages to be moved together with this, and positioning devices are disposed on the secondary carriages to abut against the reeling drum in order, together with the press devices, to fix the reeling drum so that its axis of rotation coincides with that of the coupling device of the central drive motor. Further, the central drive motor is axially movable on the secondary carriage in relation to the reeling drum to bring the coupling device of the central drive motor into engagement with the opposite coupling device of the reeling drum.

Abstract: In a known method of rebuilding a conventional tissue machine having a conventional C-wrap type twin wire forming section to a TAD machine, a TAD section, which includes a looped TAD fabric (24) and at least one TAD cylinder (22) located inside of the TAD fabric loop for thermally predrying the formed paper web (13) by passing hot air through the web, is incorporated in the machine.

Abstract: A press shoe for a shoe press with extended nip, said press shoe is of combined hydrostatic and hydrodynamic type and has a plurality of hydrostatic pressure pockets, each of which is preceded by a leading land surface and followed by a trailing land surface and into which lubricant is supplied under pressure. Each pressure pocket has a first pocket zone in which a hydrodynamic pressure shall be created and which comprises a bottom surface located at gradually decreasing depth from the concave surface portion of the press shoe seen in the direction of rotation of the belt member, said depth being zero at the trailing end of the pressure pocket. The bottom surface forms an angle .alpha. of from 0.degree. to about 2.degree. with a tangent to the concave surface portion of the press shoe at the trailing end of the pressure pocket. Further the first pocket zone is preceded by a second pocket zone comprising a plane bottom surface forming an angle .beta. of from 0.degree. to about .+-.10.degree.

Abstract: The framework for the press of a papermaking machine or the like includes interconnected opposite side frames each having two columns. Each column on the operational side of the machine has a section that is removable to permit exchange of an endless press felt and/or other belt extending through the press nip. All four columns are axially prestressed with a force exceeding by a safety margin the tensile force induced in the respective column during operation of the press. The columns preferably are box beams. They are prestressed by hydraulic nuts connected to tension rods disposed within and extending axially of associated ones of the columns. The tension rods in the columns having a removable section are formed in two parts interconnected by a quick connect/disconnect coupling that is located proximate to the removable column section. Disengagement of the coupling permits movement by an actuator of one of the two rod parts away from the other and from the removable column section.