Abstract: The invention concerns a reactive sound attenuator for air-conditioning ducts, in particular for air ducts in paper mills. The sound attenuator includes at least two chambers separated from another by means of a partition wall. The partition wall is provided with an opening or with a tube placed in the direction of flow of the air flowing through the sound attenuator, the air flowing through said opening or tube out of one chamber into the other. The main plane of the partition wall is at an acute angle in relation to the direction of air flow through the sound attenuator. Preferably, the partition wall is at an angle .alpha. from about 40.degree. to about 70.degree. in relation to the direction of air flow through the sound attention.

Abstract: The invention relates to a grouping of cylinders in a drying section of a paper machine, in which drying section a paper web and a wire are carried meandering from a first heated drying cylinder onto a leading cylinder and from the leading cylinder further onto the next heated drying cylinder. A drying group consists of a number of subsequent groupings of cylinders, whereby, in each grouping of cylinders, the drying cylinders and the leading cylinders are placed, in relation to one another, substantially at three different height levels, so that the drying cylinders with larger diameter are placed at a height level Y.sub.1 and the drying cylinders that have a diameter smaller than said larger diameter are placed at a height level Y.sub.2. In the groupings of cylinder the leading cylinders are placed at a third height level Y.sub.3.

Abstract: The invention concerns an adjustable-crown roll having a stationary roll axle which is supported on the machine frame by means of articulated bearings, and a roll mantle which is arranged to revolve on the axle. Hydrostatic loading members or an equivalent pressure fluid chamber or series of chambers are arranged in the space between the axle and the roll mantle. By means of the loading members or equivalent, the profile of a nip formed with a counter-roll of the roll is regulated. A support bushing arranged concentrically with the roll mantle is attached to one end of the roll mantle and revolves along with the roll mantle. A bearing is installed on the support bushing. The bearing receives axial forces from the roll mantle and transfers the same to the machine frame through the non-revolving bearing bock or housing of the bearing. The bearing is arranged, in the axial direction, outside the roll, whereby the roll is suitable for use as a hot roll.

Abstract: The invention concerns a press section of a paper or paperboard making machine, comprising a number of rolls (1, 11, 22, 32, 44, 70) which forms press nips (N.sub.1, N.sub.2, N.sub.3, N.sub.4) that dewater the web (W) with each other, the web being arranged to run through these nips. Of the rolls at least one roll (1;70) is a smooth-faced so-called center roll, which forms a press nip (N.sub.2, N.sub.3 ;N.sub.4) with at least one other press roll (11, 32, 44), over which a press felt (10, 30; 40), which has been formed as an endless loop, is passed to absorb water from the web (W). The center roll (1; 70) in accordance with the invention is a variable-crown roll, which comprises a metallic roll mantle (2; 71) arranged to revolve around a stationary roll axle (3; 72). The roll includes at least one set of crown-variation members (4, 5; 73), which are arranged to load the roll mantle (2; 71) in the direction of the nip plane (K.sub.2, K.sub.3 ; K.sub.

Abstract: A deflection-compensated doctor blade beam of a coater used for coating web materials. The doctor blade beam comprises a box-section frame (3), together with a holder (2) of the doctor blade (8), and a support tube (4) placed inside the frame (3). The support tube (4) is backed against the frame (3) preferably with three asymmetrically placed compensating elements (5), which advantageously are pressurized hoses. The deflection of the doctor blade beam is accomplished by varying the volume of the compensating elements (5) through pressure alterations in the elements. A displacement of desired direction can be achieved by differentially pressurizing the three compensating elements (5). By using this apparatus, the deflection of the doctor blade can be compensated to full straightness. The compensating system is controlled with the help of a feedback loop using data from a direct measurement of beam deflection, or alternatively, from the coat thickness profile.

Abstract: The inventions concerns a sound attenuator for low frequencies for air-conditioning ducts, in particular for intake-air and/or exhaust-air ducts in paper mills. The sound attenuator comprises a frame whose flow duct substantially coincides with the air-conditioning duct and in which frame there is at least one plane attenuator member parallel to the flow direction and comprising one or several attenuator units operating by the Helmholtz and/or plate resonator principle. The attenuator member or members are fitted in the frame singly or as a group of several attenuator members to be replaced for cleaning and/or servicing of the sound attenuator and/or of the attenuator members.

Abstract: The invention concerns a reeling drum for a paper or board machine or equivalent, onto which reeling drum a material web, in particular paper or board, is reeled. Axle journals have been fixed to the ends of the reeling drum in a conventional way by means of end joints. By means of the axle journals, the reeling drum is supported in a revolving manner on a machine frame by means of bearing means. According to the invention, the reeling drum is provided with articulation devices or the like for variation of the deflection of the reeling drum and for equalization of the pressure produced by the material web reeled ont the reeling drum. The reeling drum has an inner mantle supported on the machine frame revolvingly, and an outer mantle fitted on the inner mantle coaxially. A gap remains between the inner mantle and the outer mantle, the outer mantle being supported on the inner mantle by means of the articulation devices.

Abstract: Process for the manufacture of a coating bar for a bar coater, wherein the coating bar is supported substantially over its entire length revolving in a cradle fixed to the frame of the coater. The coating bar is profiled and surface-treated by boronizing.

Abstract: An assembly and method for the guided threading of a wrapper for the wrapping of cylindrical objects, including a two-part frame (2, 3), a belt-like element (8, 9) for guiding the wrapper, and elements (4, 5, 6 and 7, 10, 11) attached to the frame, suitable for transferring the belt-like element (8, 9) to rest against the roll (1). The wrapper is guided by means of a roller chain (8, 9) comprised of a plurality of freely rotating rollers (17) which are linked to each other. The assembly incorporates two pairs of support arms placed to function in opposing directions with respect to rotating direction of the roll (1), the arm pairs comprising a lower support arm (5, 7) and an upper elongated support arm (4, 6), both pivotally mounted to the frame (2, 3), crank levers (10) attached to the pivotally mounted end of each support arm, and pneumatic cylinders (11) connected to each crank lever (10), capable of rotating the support arms (4, 5, 6 and 7) via the crank levers (10).

Abstract: An absorptive sound attenuator, which is intended particularly for intake and/or exhaust air ducts in paper mills. The sound attenuator comprises a box-like duct housing (10), in whose interior there is an inner tube (19), which is provided with through perforations (19a) and which forms the air duct (20). Around the inner tube is placed sound absorbing material (21, 22). The inner tube (19) defines the air duct (20) in its interior, the sound being absorbed in the area of the air duct (20). In order to facilitate cleaning and/or replacing of the sound attenuator components and the absorption material (21,22,26) in the duct housing (10) the absorptive sound attenuator is provided with openable outer walls (13a,13b,14a,14b,13A,13B). When these walls are open, the absorption material (21,22,26) can be removed and/or replaced from outside the inner tube (19).

Abstract: Frame construction for a press section of a paper machine which comprises, in a direction of running of a paper web, first a front frame and then a separate rear frame. On the front and rear frame, press rolls are mounted, at least some of which belonging to a compact press roll combination in which there are press nips between the press rolls and through which press fabrics are passed. With a view to facilitating replacement of press rolls and fabrics, the frame construction comprises a space which is situated between the front frame and the rear frame which are not connected together, and above the press roll combination. This space is constantly at least partially open, through which the different press rolls in the combination can be replaced. This space also facilitates replacement of the press fabrics provided in conjunction therewith. Another embodiment of the invention discloses an openable connection between the front and an intermediate frame.

Abstract: A web is reeled onto successive reeling drums to form respective jumbo rolls by reeling the web onto a first reeling drum at a reeling position to form a first jumbo roll, the first reeling drum being driven by a center drive. When the first jumbo roll is full, a second reeling drum is delivered to a standby position and is accelerated to web speed. A transfer device is employed to transfer the first jumbo roll to an exchange position while the center drive remains connected thereto. The second reeling drum is transferred to the reeling position and the web is exchanged from the first jumbo roll to the second reeling drum. The first jumbo roll is decelerated and the transfer device is shifted from the first jumbo roll to the second reeling drum. The center drive is connected to the second reeling drum.

Abstract: The invention relates to a coating device for coating, e.g. a size-press roll, paper or board or of an equivalent moving base. The coating device comprises a revolving coating bar which rests against a moving base. The coating bar extends across the machine width, and is supported in a cradle substantially over its entire length. The coating bar is fitted to spread and to smooth the coating agent onto the moving base which coating agent is introduced into the coating device in the direction of running of the moving base before the coating bar. The coating bar in accordance with the invention is a smooth bar of large diameter, which is fitted against the moving base so that the profile of coating quantity can be controlled.

Abstract: The invention concerns a method and apparatus for regulating the temperature of an adjustable-crown roll. The roll mantle (12) arranged to revolve on the stationary axle (11) of the roll (10) is loaded by passing a pressure medium into a pressure chamber (15) or series of chambers formed between the axle (11) and the mantle (12) so as to correct the deflection of the roll mantle (12). The roll (10) is additionally heated/cooled by passing heating/cooling fluid into the roll (10). The heating/cooling fluid used for the regulation of the temperature of the roll (10) is introduced into the roll (10) so as to be substantially uniformly distributed over the surface area of the roll (10) such that heat is removed or produced in the radial direction of the roll.

Abstract: Closed press section in a paper machine, comprising a compact combination of press rolls. Certain of rolls define press nips with each other, between which nips the web has a closed draw supported by the face of a fabric. The press section has a center roll in connection with which a press nip or press nips are provided. A closed loop of a transfer band is passed around the center roll. The web is transferred on an outer face of the transfer band after the last press nip in the compact combination of rolls as a closed and constantly supported draw onto a drying wire in a drying section following after the press section. The transfer band loop is made of a transfer band fabric that substantially does not receive water and does not rewet the web. The web-adhesion properties of the outer face of the transfer band fabric are chosen so that, after the last nip, the web follows the transfer band fabric, and so that the web can be transferred as a fully closed draw onto the drying wire.

Abstract: A method and apparatus in the press section of a paper machine for regulating the axial linear-load profiles in its nip or nips (N.sub.1,N.sub.2,N.sub.3). The axial temperature profile(s) of the outer mantle(s) of a press roll or rolls (11, 13, 16, 17) is/are regulated. Thereby, the distribution of the diameter of the press roll in the axial direction is controlled on the basis of thermal expansion. Also thereby, the distribution in the transverse direction of the machine of the linear load in the press nip or nips (N.sub.1,N.sub.2,N.sub.3) formed by the press roll or rolls (11, 13, 16, 17) is affected. The temperature profile of the outer mantle(s) (11', 13',17') of the press roll or rolls (11, 13, 17) is regulated by a press felt or felts (10, 14, 18) running through the press nip or nips (N.sub.

Abstract: The invention concerns a roll for use in the production of paper, in particular a center roll in a press section of a paper making machine, with which the web is in direct contact and from which the web is detached. In the invention, a composite structure has been formed onto the cylinder mantle of the roll. According to the invention, the roll face is provided with a surface layer which protects the roll from wear and which provides good properties for detaching of the web, this surface layer being formed by thermal spraying of a powder wherein metal and ceramic phases are in the same powder particle. The roll face is additionally provided with a dense layer for protection against corrosion, which layer is made of stainless steel whose chromium content is 10 to 29% and which layer is placed between the surface layer and the roll mantle. The function of the layer for protection from corrosion is to protect the roll mantle from corrosion and to promote the adhesion of the surface coating to the roll.

Abstract: The invention concerns a steam and condensate coupling for a drying cylinder in a paper machine. The steam and condensate coupling includes a piston ring having a seal therein. This stationary, nonrevolving seal is pressed by means of steam pressure against the revolving axle or against a flange part or equivalent permanently connected to said axle. A piston ring is located in the coupling, which includes a face placed substantially perpendicularly to an axial direction of the cylinder, or slightly inclined from the perpendicular plane. In the coupling construction, steam pressure is passed onto the face of the piston ring, and a force is produced. By this force, the piston ring and the seal are pressed toward the revolving axle. Thereby, by means of the steam pressure, a pressure-tight joint is provided between the seal and the revolving axle.

Abstract: A paper machine for manufacturing a soft crepe paper web, comprising a wet end (1) having a forming wire (4) for forming and carrying a paper web (7), and a drying section (2) provided with a drying cylinder (12), said paper machine having a first operating arrangement for manufacturing a soft crepe paper web with certain bulk and softness values, in which first operating arrangement the drying section has a felt (13) arranged to run in a loop from a pick-up roll (14) at the transition between the wet end and drying section, to a press roll (15) at the drying cylinder, and the carrying forming wire runs up to the pick-up roll (14) to transfer the paper web to the felt (13).

Abstract: The surface properties of a roll and/or rolls in a paper machine are affected by regulating the temperature of the roll face by means of an external heating device. In the arrangement, a combination of a heating device and a roll coating is used in such manner that the heating radiation penetrates through the paper or only directly to the roll face, but does not heat the roll itself at a depth greater than the roll face. The roll coating is preferably made of a dark, readily heatable and insulating material. The arrangement of the invention is utilized for example in a calendar and for detaching the paper from a roll.