Abstract: The present invention relates to a method and apparatus for coating a moving paper web (2), in which method the web (2) to be coated is passed to a coater station and the coating is applied to at least one surface of the moving web (2) by means of spraying nozzles (1) disposed in the interior of an enclosing hood (9). The web (2) is supported noncontactingly by means of air jets directed toward at least one side of the web (2).

Abstract: A method and an assembly is disclosed for coating a web (1) of paper or board by a dry treatment agent, the method comprising the step of applying the treatment agent to at least one side of the moving web (1). In the method is used a treatment agent contains a binder capable of undergoing a change of state at least under the effect of elevated temperature. The web (1) after being treated with the treatment agent is subjected to at least an elevated temperature at which the binder becomes deformable, and the web is subjected to a lower temperature serving to set the binder so that the same bonds the treatment agent to the web surface. The solids content of the treatment agent is not less than 75%, preferably not less than 90%, whereby a drying step after the treatment is not required.

Abstract: A method and apparatus for manufacturing paper, in which method base paper manufactured in a paper machine is calendered and coated to improve its printing properties. Before calendering, the moisture content of the manufactured base paper is brought to 4-14% of the total weight of the paper, after which the base paper web (2) is taken to a multi-nip calender (3), the base paper being calendered by the multi-nip calender (3) and the calendered base paper (2) coated on at least one side with a layer of coating.

Abstract: The object of the invention is a method for defining the profile of a coating layer of a paper or board web (2). The method comprises application of a coating slip to at least one surface of the web (2) at the coating head (1) of a coating machine, the measurement of the transverse temperature profile of the web (2) surface in at least a measuring point (7, 8) fitted after the coating head (1), and the definition of the profile of the web's (2) coating layer on the basis of the temperature profile measured in at least the measuring point (7, 8) fitted after the coating head (1), whereupon a change in the temperature of the web's (2) coating layer or in the difference of the temperature between the coating layer and the base web (2) is at least almost proportional to the change in the coat weight.

Abstract: A method and an assembly is disclosed for manufacturing a web of glazed paper or board so as to produce with a web surface treated with a treatment agent, the method comprising the steps of first producing a base web (10), whereupon in an applicator apparatus to the surface of the web is applied in at least one step at least one kind of a treatment agent. Subsequent to the application of the treatment agent, the web (10) is passed via a dryer. The solids content of the treatment agent to be applied the surface of the web (10) in an applicator apparatus is not less than 80 %, and after the application of the treatment agent, the web (10) is passed via a belt dryer comprising at least one heatable belt (2) in such a manner that the heatable belt comes to face the treated surface of the web (10). Advantageously, the web has a high moisture content prior to the application of the treatment agent.

Abstract: The present invention relates to an apparatus for controlling the behavior of particulate matter such as mist and dust occurring in the manufacture of paper and board. A web (1) is passed to web treatment equipment (22, 23) wherein at least one treatment step is applied to the web (1) causing the emission of said particulate matter (24). In the vicinity of the emission point (21) of said particulate matter are placed at least two electrodes (25, 26) and at least one electrode, called a counter-electrode (26), is at a low potential. Further, at least one electrode (25) is at a potential higher than that of said counter-electrode (26), and the potential difference between said electrodes (25, 26) is made so high as to generate a corona discharge between said electrodes that causes an ion-blast wind toward the electrode (26) of the lower potential, said ion-blast wind being capable of transferring particular matter, which enters the gap between said electrodes, toward said electrode of lower potential.

Abstract: Method and apparatus for guiding a web of paper or board or, alternatively, an edge strip sheared therefrom, in a paper machine or finishing equipment, the method being particularly suited for threading the web tail or edge strip through the machine in conjunction with a production shutdown or after a web break. According to the invention, the web (6) or its tail sheared from the web so as to form an edge strip is supported electrically by means of taking surfaces or electrodes (3, 5) disposed on opposite sides of the web (6) to different potentials. Particularly advantageously, the web (6) or the edge strip can be adhered to a roll (16), a belt (7) or a wire by taking said support element to a lower potential and disposing a higher-potential electrode (5) or a number of electrodes to the opposite side of the web.

Abstract: A method for controlling particulate matter occurring in the manufacture of paper and board. A web (1) is passed to web treatment equipment (22, 23) wherein at least one treatment step is applied to the web (1) causing the emission of particulate matter (24). In the vicinity of the emission point (21) of the particulate matter are placed at least two electrodes (25, 26) and at least one electrode, called a counter-electrode (26), is at a low potential. At least one electrode (25) is at a potential higher than that of the counter-electrode (26), and the potential difference between the electrodes (25, 26) is made to generate a corona discharge between the electrodes that causes an ion-blast wind toward the electrode (26) of the lower potential, the ion-blast wind transferring particulate matter, which enters the gap between the electrodes, toward the electrode of lower potential.

Abstract: Apparatus and method for coating a moving paper web, in which the web to be coated is first guided to a coating station correctly aligned and a first side of the web is coated with a coat layer. Next, the web is guided upwards from the coating station and the first coat layer is dried using non-contact dryers. From the dryers the web is guided to the next coating station correctly aligned, and the second side of the web is coated with a coat layer, the web is guided upwards from the coating station and the coat layer on the second side of the web is dried using non-contact dryers. When the web is directed from the coating station through the dryers, it is guided non-contactingly by means of air jets such that the web is first non-contactingly turned in the machine direction during drying and next, similarly during drying, towards the level of the coating stations.

Abstract: The present invention relates to a method and assembly for controlling the behaviour of particulate matter such as mist and dust occurring in the manufacture of paper and board. In the method, a web (1) is passed to web treatment equipment (22, 23) wherein at least one treatment step is applied to the web (1) causing the emission of said particulate matter (24). According to the method, in the vicinity of the emission point (21) of said particulate matter are placed at least two electrodes (25, 26) and at least one electrode, called a counter-electrode (26), is taken to a low potential.

Abstract: Apparatus and method for coating a moving paper web, in which the web (2) to be coated is first guided to a coating station (7) correctly aligned and a first side of the web (2) is coated with a coat layer. Next, the web (2) is guided upwards from the coating station (7) and the first coat layer is dried using non-contact dryers (8, 9). From the dryers the web (2) is guided to the next coating station (14) correctly aligned, and the second side of the web (2) is coated with a coat layer, the web (2) is guided upwards from the coating station (14) and the coat layer on the second side of the web (2) is dried using non-contact dryers. When the web is directed from the coating station (7) through the dryers (8, 9), it (2) is guided non-contactingly by means of air jets such that the web (2) is first non-contactingly turned in the machine direction during drying and next, similarly during drying, towards the level of the coating stations (7, 14).

Abstract: The present invention relates to a nozzle device for use in a spray coating station designed for coating a paper or board web, said device comprising a nozzle device body (1), a replaceable nozzle piece (2) and clamping member and actuator (3,4) suited to lock said nozzle piece (2) to said nozzle device body (1). New nozzle pieces (2) are stored in a nozzle replacement apparatus (5,6) which facilitates rapid replacement of an in-use nozzle piece (2). In the replacement operation, the clamping member and actuator (3,4) serving to lock said nozzle piece (2) are first actuated in order to release said nozzle piece whereafter the worn nozzle piece (2) is removed with the help of transfer member (6) and a new nozzle piece (2) is moved to the nozzle device, and finally said new nozzle piece (2) is locked by said clamping member and actuator (3,4) to said nozzle device body (1).

Abstract: Apparatus and method for coating a moving paper web, in which the web (2) to be coated is first guided to a coating station (7) correctly aligned and a first side of the web (2) is coated with a coat layer. Next, the web (2) is guided upwards from the coating station (7) and the first coat layer is dried using non-contact dryers (8, 9). From the dryers the web (2) is guided to the next coating station (14) correctly aligned, and the second side of the web (2) is coated with a coat layer, the web (2) is guided upwards from the coating station (14) and the coat layer on the second side of the web (2) is dried using non-contact dryers (8, 9). When the web is directed from the coating station (7) through the dryers (8, 9), it (2) is guided non-contactingly by means of air jets such that the web (2) is first non-contactingly turned in the machine direction during drying and next, similarly during drying, towards the level of the coating stations (7, 14).

Abstract: An apparatus for coating a paper web in which a coating mix is applied onto a paper web using an applicator unit which forms a linear mechanical force on the web against a first backing surface situated on the back side of the web. The coating mix applied onto the web is doctored using a doctor unit acting against a second backing surface. The speed of at least one of the backing surfaces is independently controlled relative to the speed of the first backing surface and the web speed in order to attain control of the tensile stress of the web.

Abstract: A method and apparatus for coating a moving web of paper of paper-board. In the method, the web to be coated is passed to a coater station, wherein a coat layer is applied to at least one surface of the web, and the web is dried at least to some degree and passed to the next treatment step. The coat is applied by spraying the coating mix on the web surface by a high-pressure spraying nozzles, the pattern width covered by a single nozzle is essentially narrower than the cross-machine width of the web being coated.

Abstract: A method and apparatus for coating a moving web of paper or paperboard. The web to be coated is passed to a coater station, wherein a coat layer is applied to at least one surface of the web by means of high-pressure spraying nozzles, whereby the pattern width covered by a single nozzle is essentially narrower than the cross-machine width of the web being coated. The nozzles are located in an enclosure and the excess coat mist formed in the process is removed by means of suction tubes, and advantageously, with the help of a falling film of coating mix flowing down the internal wall(s) of the enclosure.

Abstract: An apparatus and method for preventing plugging of a narrow, slot-orifice-type jet nozzle 6 used in a paper and board coater in which the jet nozzle extends over the entire cross-machine width of the web being coated. The coater has an application chamber 11, a coating mix infeed channel 5 connected thereto and a clot orifice 6 as well as at least one inlet port 13 for feeding the coating mix into the application chamber 11. An easily cleanable strainer element 12 is placed close to the applicator apparatus to separate aggregates of the coating mix that otherwise could plug the slot orifice 6.

Abstract: A method for calendering a web such as a paper web in a multi-nip calender or supercalender, in which the web is passed through calendering nips formed by rolls placed in two or more stacks of rolls. The web is passed alternatingly from the corresponding calendering nip in each stack of rolls into the calendering nip in the following stack of rolls. In other words, the web is passed from a first calendering nip in a first stack of rolls to a first calendering nip in a second stacks of rolls, after the first calendering nip in the second stack of rolls to a second calendering nip in the second stack of rolls, from the second calendering nip in the second stack of rolls to a second calendering nip in the first stack of rolls, and after the second calendering nip in the first stack of rolls to further processing.

Abstract: A method and apparatus for coating a moving paper or cardboard web, in which the moving web is brought to a first backing roll and coating mix is metered onto the web by means of a pre-doctoring blade in the form of a high-velocity laminar flow in front of the pre-doctoring blade. The applied coating mix is smoothed evenly onto the web with the pre-doctoring blade and the coated web is brought to a second backing roll, where the applied coating mix is smoothed using a doctor blade working on the web supported by the second backing roll. The tension of the web is measured upstream from the first backing roll and the rotational speed of the second backing roll is set so that the tension of the web is set at a desired value. The rotational speed of the first backing roll is set so that a speed difference between the first and the second backing roll compensates for elongation of the web caused by wetting between the first and second backing rolls.