Metso Paper Inc.

Valmet Corporation

Metso Paper Automation Oy

Timo Torvi

Petter Honkalampi

Thomas Berglind

Pekka Koivukunnas

Nils-Erik Safman

Kari Hasanen

Nils-Erik S&auml;fman

Matti Lares

Petteri Venetjoki

Helena Lepp&auml;skoski

Helena Lepp&auml;koski

Higher-gloss paper grades, in particular paper grades with a Hunter gloss % above 40, are produced in an arrangement having pairs of calendering units () disposed in the machine direction one after the other and apart from one another, which pairs are each formed of separate and different calendering units () and in each of which the nip load in the latter calendering unit () is higher than the nip load in the preceding calendering unit (). Advantageously, the calendering unit () placed first in the machine direction is an on-line long-nip calendering unit () and the calendering unit () placed after that in the machine direction is an on-line or off-line supercalender.

Calendering arrangement for a paper machine

The invention relates to a method for positioning a shoe of a shoe press/shoe clender in a paper machine. In the method, the position of the shoe ( ) of the shoe calender/shoe press is measured and, based on the results of the measurement, the position of the shoe is controlled so as to be as desired in the direction of nip compression. The invention also relates to an arrangment for positioning a shoe of a shoe press/shoe calender in a paper machine, which arrangment comprises a shoe roll ( ) or equivalent which includes a shoe ( ) and hydraulic cylinders ( ) connected thereto for moving the shoe ( ). The arrangement comprises further at least two measuring devices ( ) for measuring the position of the shoe ( ) and means ( ) for controlling the position of the shoe ( ) based the results obtained by means of the measuring devices so as to be as desired in the direction of nip compression.

Method and arrangement for positioning a shoe of a shoe press/shoe calendar in a paper machine

The invention relates to a method for operating a calender, comprising a cylindrical heated roll and a flexible belt surrounding a stationary support beam which supports at least one actuator which may urge a concave load shoe against the heated roll by the flexible belt to form an extended and heated nip through which a fiber web passes to be calendered and a separating mechanism for having at least one of the rolls movable into and away from the nip characterized in that the flexible belt is a flexible tubular jacket which forms a part of an enclosed shoe roll such that the ends of the jacket have end walls mounted thereto, which end walls are rotatably mounted in relation to the support beam, and in that at least one of the end walls is driven by a drive arrangement which drive arrangement may be activated to drive the end walls and thereby also the jacket independently of its position in relation to the fiber web or the heated roll.

Method and apparatus for calendering paper

The present invention relates to a method for calendering a moving web ( ) of paper or board. The web ( ) is passed to a calender ( ) and calendered therein. At least one quality of the calendered web ( ) is measured at a first measurement point ( ) adapted at a location downstream from the calender ( ). Additionally, at least one quality of the web ( ) entering the calender ( ) is measured at a second measurement point ( ) adapted at a location between the calender ( ) and the preceding section of the line. A control variable ( ) affecting the calendering effect on the calender ( ) is controlled by a feedback control scheme based on the measurement result obtained from said first measurement point ( ) and a control variable ( ) affecting the processability of the web ( ) to be calendered is controlled by a feedback control scheme based on the measurement result obtained from said second measurement point ( ).

Method for calendering

The invention relates to a method and apparatus for measuring the tension of a moving web. In the invention, a measuring beam ( )is curved so that a web moving over or under the measuring beam ( ) forms an air cushion ( ) of the air it transports between the measuring beam ( ) and the web ( ). The web ( ) causes a force effect transmitted by the air cushion on the measuring beam ( ). The tension of the web ( ) is measured by measuring the force caused by the web ( ) and transmitted by the measuring beam ( ).

Method and apparatus for measuring the tension of a moving web

The invention relates to an apparatus for calendering a fiber web, wherein the fiber web passes through an extended and heated nip, said nip being formed on one side by a cylindrical heated roll and on the other side by a flexible tubular jacket which is pressed against the heated roll by means of a concave load shoe, said tubular jacket surrounding a stationary support beam which supports at least one actuator which may urge said load shoe and said flexible tubular jacket against said heated roll, and wherein the extension of the load shoe in the axial extension is less than the axial extension of the jacket and the heated roll such that when the load shoe is urged against the heated roll there will be formed tapered sections at each side end of the jacket within the nip wherein said tapered section are substantially covered by said fiber web such that a small strips of the fiber web at each edge is not calendered in said extended nip.

Apparatus for calendering paper

The invention relates to a method for operating a calender, comprising a cylindrical heated roll and a flexible belt surrounding a stationary support beam which supports at least one actuator which may urge a concave load shoe against the heated roll by means of said flexible belt to form an extended and heated nip through which a fiber web passes to be calendered and a separating mechanism for having at least one of the rolls movable into and away from the nip characterized in that said flexible belt is a flexible tubular jacket which forms a part of an enclosed shoe roll such that the ends of said jacket have end walls mounted thereto, which end walls are rotatably mounted in relation to said support beam, and in that at least one of said end walls is driven by means of a drive arrangement which drive arrangement may be activated to drive the end walls and thereby also the jacket independently of its position in relation to the fiber web or the heated roll.

The invention relates to a method and an apparatus calendering a fiber web, wherein the fiber web passes through an extended and heated nip, said nip being formed on one side by a cylindrical heated roll and on the other side by a flexible tubular jacket which is pressed against the heated roll by means of a concave load shoe, said tubular jacket surrounding a stationary support beam which supports at least one actuator which may urge said load shoe and said flexible tubular jacket against said heated roll, and wherein the extension of the load shoe in the axial extension is less than the axial extension of the jacket and the heated roll such that when the load shoe is urged against the heated roll there will be formed tapered sections at each side end of the jacket within the nip characterised in that said tapered section are substantially covered by said fiber web such that a small strips of the fiber web at each edge is not calendered in said extended nip.

Growing community of inventors

Järvenp{umlaut over (aa)}, Finland

Timo Torvi