Valmet Paper Machinery Inc.

Metso Paper Inc.

Metso Automation Oy

Valmet Technologies, Inc.

Hannu Korhonen

Rauno Verner Rantanen

Markku Lummila

Ari Puurtinen

Michael H Odell

Antti Poikolainen

Jyrki Huovila

Jukka Koskinen

Pekka Pakarinen

Antti Leinonen

Juha S Kinnunen

Petri Paloviita

Mari Taipale

Timo Lintula

Sami Anttilainen

Jeffrey C Irwin

Jussi Rajala

Minna Partonen

Jukka Muhonen

Fibrous stock is supplied by a paper or board machine headbox () between looped forming wires (). Water is removed in a first dewatering zone (Z) formed with a fixed forming shoe () having a curved surface against which a wire () is supported while the opposite wire () is unsupported in the area of the shoe (). Water is removed in a second dewatering zone (Z) formed by fixed dewatering blades () on the other side of the wires () and supported against the stock therebetween () and on the opposite side of the wires () by dewatering blades (), loaded in a controlled manner against the fixed dewatering blades () at gaps () between these so that pulsating dewatering is caused in the second zone (Z). The wires () are guided so the shoe () causes essentially non-pulsating dewatering in the stock.

Forming of a paper or board web in a twin-wire former or in a twin-wire section of a former

Adjusting the operation of a wire section, in which the development of the consistency of stock on the wire section () is determined and the effect of the consistency determined above on the formation and/or porosity of a paper web () is determined. The consistency developed on the wire section is adjusted based on a quality property of paper and/or by optimising a cost function, the quality property of paper comprising the formation and/or the porosity and/or a combination defined by means of the formation and/or the porosity and the cost function including the effect of at least the formation and/or the porosity.

Method and apparatus for adjusting operation of wire section

A method for treating a web of paper or board with a wetting substance or calendering the web prior to the cylinder dryer section of a paper- or boardmaking machine while the solids content of the web is still very low, typically in the range of 10&#x2013;60%, wherein the web can be conveyed when so desired fully supported from the wire section of the paper- or boardmaking machine up to the winder, while simultaneously utilizing the quality benefits obtained from a controlled reduction of the web moisture content and dewatering of the same. The web is conveyed supported by a transfer belt () through at least one web surface treatment apparatus such as a coater station (S1B) or a calender prior to passing the web to the first dryer cylinder group () of the paper- or boardmaking machine. One nip () supported by a transfer belt () is suitable for dewatering simultaneously with the application of a treatment substance to the web. The dewatering nip () may be formed between a transfer belt () and the wire () of the wire section or the felt () of the press section.

Method and apparatus for handling a paper or board web

The invention concerns a method for optimizing the degree of flocculation in a headbox. The degree of flocculation is measured continuously from a stock flow (M )/stock flows by means of a detector (R ) of flocculation, and the detector (R ) transmits a signal to a regulator (H ), which regulates the metering of retention agent ( ) and/or fillers ( ) and/or auxiliary chemicals ( ) into the stock flow (M )/stock flows continuously on the basis of the signal to an optimal level, which stock flow/flows is/are passed into the headbox (P ).

Method for optimizing the degree of flocculation

The invention relates to a coating method and device for coating a size-press roll, paper or board or a corresponding moving base. The coating device comprises a revolving coating bar which rests against the moving base and extends across the machine width. The coating bar is supported in a cradle substantially over its entire length and is a large-diameter grooved bar fitted against the moving base. The coating bar spreads and smoothes a coating agent onto the moving base. The coating agent is introduced into the coating device in advance of the coating bar in the running direction of the moving base.

Method and device for coating a size-press roll, paper, or board

A method and apparatus for limiting the width of a coating and/or preventing damage to roll ends while coating or surface-sizing paper or an equivalent web material in a coating device in which a coating agent, such as size, coating paste or equivalent, is introduced into the coating device to an application zone defined by a coating member, a moving base, lateral seals, and a front wall and spread onto the moving base by the coating member which is loaded against the moving base. Liquid jets are sprayed into the areas outside the coating width, substantially over the width defined by the lateral seals and the roll ends, either onto the moving base before the coating member in the running direction of the moving base or directly into the nip formed by the moving base and the coating member. The liquid jets lubricate the nip and dilute the coating agent that has entered into the areas outside the coating width. The excess amount of the sprayed liquid is collected and removed to prevent entry of the excess amount of the sprayed liquid into a recirculation system the coating agent and prevent the coating agent from being diluted.

Method and apparatus for limiting the coating width and/or preventing

A method and device for keeping a coating rod and a rod cradle in a bar coater clean and for preventing leakage of the lubrication and/or cooling water used in the bar coater is disclosed. The invention is intended for a bar coater in which the coating rod is, supported revolvingly in a rod cradle substantially over its entire length. The rod cradle is attached to the frame constructions of the coater. The rod cradle is also provided with at least one groove substantially parallel to the coating rod and open towards said coating rod, in which grooves(s) water is circulated to lubricate, cleanse and/or cool the coating rod and the rod cradle. The coating rod is loaded towards the base to be coated by loading the rod cradle. The rod cradle and the sealing lips of the rod cradle are loaded so that the loading seals the glide faces between the coating rod and the rod cradle substantially over the entire length of the rod cradle and prevents leakage, or at least substantially reduces leakage, from the water grooves.

Method and device for keeping a coating rod and a rod cradle in a bar

The invention concerns a method for coating of a moving base, such as the face of a back-up roll, paper or board web, or equivalent, with a coating agent. In the method, a blade coater is employed in which a coating blade included in the blade coater and installed in a blade holder is loaded in the area between the blade holder and the tip of the coating blade toward the moving base by means of a loading member. The coating blade forms a substantially small angle in relation to the moving base. The coating quantity applied onto the moving base is regulated by adjusting the blade angle and/or the loading of the coating blade. The coating blade is loaded towards the moving base, in the area between said loading member and the tip of the coating blade. The coating blade is additionally loaded by a second loading member so that the loading produced by the second loading member prevents separation of the tip of the coating blade from the layer of coating agent formed on the moving base so as to prevent cavitation in the area of the tip of the coating blade. The invention also concerns a device that makes use of the method.

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Jyväskylä, Finland

Hannu Korhonen