Abb Oy

Abb Schweiz Ag

Jukka Gruzdaitis

Ari Leppä

Tapio Talvitie

Pertti Vainio

A winding machine for winding a finishing roll having a radius R of a sheet material on a core having a radius ris provided. The winding machine includes: a support drum assembly arranged on a first side of the finishing roll and configured to support the finishing roll from the first side; a rider roll arranged on a second side of the finishing roll opposite to the first side and configured to apply a first nip pressure onto the finishing roll from the second side the finishing roll being supported by the support drum assembly; and a control unit configured to adaptively control the second nip pressure applied by the rider roll onto the finishing roll depending on an ascent rate of the rider roll.

Winding machine and method for controlling a second nip pressure

A method and apparatus are provided for decelerating an inverter-controlled machine reel in a paper machine. The method includes detecting a break in a paper web from a machine reel, determining the inertia of the machine reel, determining continuously the angular speed of the machine reel, and determining continuously the torque required to decelerate the machine reel, on the basis of the determined inertia and angular speed, for the purpose of stopping the machine reel in a predefined time. The method also includes decelerating the machine reel electrically to stop the machine reel, in accordance with the determined torque, and using a mechanical brake when the rotation speed of the machine reel is lower than a predefined rotation speed and when the torque obtained by electrical deceleration is too small to stop the machine reel in a predefined time.

Method and apparatus for decelerating a machine reel of an unwinder

A method and arrangement are provided in connection with a continuous material web, which runs from an unwinder to a winder, at least one of which being a center winder. The method includes providing an initial value for density of a material on the center winder, calculating a moment of inertia for a roll of material on the center winder, determining tightness of the material web, producing a correction term for torque calculation based on a material web tightness reference, the material web tightness and the moment of inertia of the roll of material, calculating a torque reference based on the produced correction term and the calculated moment of inertia of the roll of material, and controlling the torque of the center winder based on the torque reference. The method also includes correcting the density value of the material on the center winder based on the produced correction term.

Method and arrangement in connection with winder drive

The invention discloses a method for controlling an electric drive that drives reels of a slitter in the paper machine. In the method at least speed and acceleration/deceleration of a slitter is controlled. According to the invention a limit value of the electric drive is defined in the method, values of at least two or more parameters effecting to the electric drive is monitored, a reference value of the acceleration/deceleration is defined on the basis of at least two parameters, and the electric drive is controlled so that the acceleration/deceleration corresponds to the highest possible reference value, by which the reference value of the acceleration/deceleration defined on the basis of any parameter is not exceeded, and that the limit value of the electric drive is not exceeded.

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Vantaa, Finland

Jukka Gruzdaitis