Abstract: The invention relates to a method and an apparatus for controlling a coloring process. In the coloring process, at least one fluorescent or non-fluorescent ingredient is added and the color of the substrate is determined by using a coloring model which describes the effect of said ingredient on the radiance transfer factor for the substrate to be colored.
Abstract: The invention relates to a method and an apparatus for measuring properties of a moving web, a sensor (1) being arranged on a first side of the moving web (7), the sensor comprising a differential coil (3), which comprises at least two coils, and a reference plate (4). A sensor plate (6) is arranged on a second side of the moving web (7). Electric current is used to induce a voltage to the differential coil (3). The voltage of the differential coil (3) varies as the web (7) changes the effect caused by the sensor plate (6) to the differential coil. The properties of the web (7) are determined by measuring the voltage of the differential coil (3).
Abstract: The invention relates to a method and equipment for controlling properties of paper, in which method the effect of the flow of retention agent (Fra) and the stock flow (Fts) on the basis weight of the paper (BW) is modelled. The fulfilled modelling is used to adjust the basis weight of the paper (BW) by controlling simultaneously the flow of retention agent (Fra) and the stock flow (Fts).
Type:
Grant
Filed:
November 17, 1998
Date of Patent:
December 11, 2001
Assignee:
Metso Paper Automation OY
Inventors:
Taisto Huhtelin, Risto Kuusisto, Lin Tian, Timo Rantala, Jukka Nokelainen
Abstract: The invention relates to a method and equipment for controlling properties of paper, which method comprises modelling the effect of the flow of retention agent (Fra) both on the amount of filler in the white water and on the paper ash content (ASH), and the effect of the flow of filler (Ffi) both on the paper ash content (ASH) and on the amount of filler in the white water. The fulfilled modelling is used to adjust the amount of filler in the white water and the paper ash content (ASH) by controlling simultaneously the flow of retention agent (Fra) and the flow of filler (Ffi).
Type:
Grant
Filed:
November 17, 1998
Date of Patent:
November 20, 2001
Assignee:
Metso Paper Automation Oy
Inventors:
Taisto Huhtelin, Risto Kuusisto, Lin Tian, Timo Rantala, Jukka Nokelainen
Abstract: A method for blowing steam against a paper web, whereby the steam is blown by a steam box having several profiling chambers in the cross direction of a paper machine. The cross-profile of the paper web is controlled by means of the steam supplied by the profiling chambers. A gas flow is provided between the profiling chambers to prevent the steam blown by a profiling chamber from affecting the effective area of the steam blown by the adjacent profiling chamber. Further, a steam box for implementing the method is disclosed.
Abstract: The invention relates to a method and apparatus for measuring paper color. Paper color is measured from the surface of a paper roll on a winder.
Abstract: The invention relates to a method and apparatus for measuring the caliper of paper substantially continuously during papermaking. A sensor (3a, 3b) is arranged above and/or under the paper (2), the sensor (3a, 3b) measuring the caliper of the paper (2) at least on one side of the paper (2) mainly without contacting the surface of the paper (2). At given intervals the sensor (3a, 3b) measuring mainly without contact is brought into momentary contact with the surface of the paper (2).