Abstract: A method and equipment for measuring the tension of a moving web. The tension of the moving web is measured by means of a measuring element provided with a guide surface which the moving web is guided to pass such that the web forms an air cushion of the air it carries between the web and the guide surface. Measuring devices are arranged at a distance from one another in connection with the measuring element in the cross direction of the web for measuring a variable representing the tension of the moving web. The measuring element is moved back and forth in the cross direction of the web such that the tension profile of the web is measured at least on a part of the web width by means of the measuring devices arranged in connection with the measuring element.

Abstract: A method of blowing drying gas against a paper web, and an impingement dryer of a paper machine. Drying gas is blown with an impingement dryer comprising several profiling chambers in the cross-direction of a paper machine, the cross-profile of the paper web being controlled with the drying gas blown from the profiling chambers. Each profiling chamber blows drying gas to its own effect range. The impingement dryer further comprises a return air chamber and return air ducts such that drying gas blown against the paper web from the profiling chambers is returned into the return air chamber through the return air ducts in such a way that some of the effect of the drying gas blown from the profiling chamber is at least partly prevented from reaching the effective area of the adjacent profiling chamber.

Abstract: A method and apparatus for sootblowing a recovery boiler. Sootblowers of the recovery boiler are divided into sootblowing groups, and a sootblowing interval is determined for the sootblowers. A fouling index is produced for each sootblowing group of the recovery boiler, and relative frequency values are calculated.

Abstract: The invention relates to a method and arrangement for measuring optical properties from paper or board that constitutes a target to be measured and comprises two planar surfaces. In the arrangement, one surface of the target to be measured is illuminated by an optical power source, and the illuminated area on the opposite side of the illuminated surface comprises at least one backing with known optical properties. A detector detects the illuminated surface in the area of the backing, and at least one optical property of the target to be measured is determined by means of spectral information obtained at the backing.

Abstract: The measuring device comprises at least one measuring head having a reference part, which comprises a reference surface against which the moving web is supported. The reference surface comprises a measuring area in the inside of which the property of the web is measured. The reference part is arranged in connection with the measuring head in such a way that below the reference part, there is a substantially open air space. The measuring head comprises means for generating negative pressure in the air space below the reference part, and the reference part comprises holes formed through it, in such a way that the negative pressure generated in the air space affects through the reference part the space between the reference surface and the moving web in such a way that the web is supported against the reference surface substantially over the whole area of the measuring area.

Abstract: The invention relates to a method and an apparatus for measuring a coating from paper or board. The measurement is carried out by one detector at different times or by two detectors simultaneously. IR radiation directed at the coating and radiation emerging from the coating are chopped synchronously in blocks. A wavelength band sensitive and insensitive to the absorption are bandpass filtered and measured in both the MIR and NIR region. The absorption strength is measured in a digital signal processing block by comparing the radiation sensitive to absorption to the radiation insensitive to absorption, and the amount of each coating component is determined in the digital signal processing block on the basis of the absorption strength.

Abstract: The invention relates to a method and a measurement device for measuring a suspension which contains wood fibers, the method comprising directing optical radiation at pulp and measuring optical radiation emitted by the pulp. The solution comprises measuring at least one of the following two properties; kappa number and brightness. The solution comprises changing the pulp consistency in a desired range of consistency extending from a desired initial consistency to a desired final consistency. The pulp consistency and the strength of a desired wavelength from the optical radiation are measured in the desired consistency range. Measurement points are modeled with a function of the desired type by fitting the parameters of the function according to the measurement points. Finally at least one of the following two properties of the pulp is determined by means of the modeling function; kappa number and brightness.

Abstract: A method of monitoring the condition of apparatuses wherein the condition of the apparatus is measured from one or more rotating objects by means of a fixedly mounted condition monitoring system during the operation of the apparatus when it operates at its normal operating speed. In the method, at least one signal indicating the condition of the apparatus and the steadiness of the operation is measured during the change in the operating speed of the apparatus and desired characteristic values and/or functions are calculated from each signal measured in this manner as a function of measured time and/or rotational speed.

Abstract: The invention relates to method and equipment for monitoring the operation of an industrial process. The industrial process is used as a basis for compiling a document comprising a group of cause-effect relationships dependent on the industrial process. From the industrial process is collected status data of the process. A document server compares the process status data with the data provided by the group of cause-effect relationships and produces a plain-language account of the status of the industrial process.

Abstract: A device for heating a roll in a paper or paperboard machine or in a finishing machine for paper or paperboard the device including a profiling induction heater (5) which is arranged to heat the roll (3) with a power dependent on the location of the point to be heated in the axial direction of the roll, and a non-profiling induction heater (4) which, to provide basic heating, is arranged to heat the same roll (3) with a heating power which is substantially even over the width of the roll (3). The profiling induction heater (5) and the non-profiling induction heater (4) are placed in the same support structure (1) outside the roll (3). The roll (3) is a calender roll.

Abstract: The invention relates to a method and arrangement for measuring optical properties from paper or board that constitutes a target to be measured and comprises two planar surfaces. In the arrangement, one surface of the target to be measured is illuminated by an optical power source, and the illuminated area on the opposite side of the illuminated surface comprises at least one backing with known optical properties. A detector detects the illuminated surface in the area of the backing, and at least one optical property of the target to be measured is determined by means of spectral information obtained at the backing.

Abstract: A method and an apparatus for controlling a moisture profile of a paper web, in which the moisture profile of the paper web prior to drying is measured. The measurement is carried out with a measuring device, which measures a cross-direction profile of the web substantially simultaneously. On the basis of the measurement, the moisture profile of the paper web is controlled prior to drying the paper web.

Abstract: A multivariable analysis tool is provided wherein an orthogonal decomposition method such as a Partial Least Squares algorithm is applied to a disturbance model, which relates the known loop disturbances to the loop model residue. The tool according to the invention first extracts the most dominant correlation to the loop model residue and then uses the residue to search for secondary dominant correlation in an orthogonal space, and repeats this process until no further output variation can be significantly attributed by the next dominant correlation. In this way, the analysis tool of the present invention is able to estimate the performance potential of each control loop under different disturbance conditions and provide a control performance index by comparing the achieved performance to the performance potential in a multi-variable environment. This index indicates whether or not a given loop is under optimal operation and shows variance of the loop from the best achievable loop performance.

Abstract: A method and apparatus for sootblowing a recovery boiler. Sootblowers of the recovery boiler are divided into sootblowing groups, and a sootblowing interval is determined for the sootblowers. A fouling index is produced for each sootblowing group of the recovery boiler, and relative frequency values are calculated.

Abstract: The invention relates to a method and an apparatus for measuring the amount of silicone coating on a moving paper or board web. In the invention, the characteristics of the coating (4a) are measured by means of reflection measurement or transmission measurement. The amount of the silicone in the coating is measured by measuring an absorption peak that is characteristic of the silicone in the mid-infrared range.

Abstract: A variable representing runnability of a paper web to be manufactured with a paper machine or processed with a finishing apparatus is measured and the speed difference between operational groups of the paper machine and/or the finishing apparatus is adjusted on the basis of the measurement of said variable such that the moisture profile of the paper web is measured substantially along the entire width of the paper web, the minimum and maximum values for moisture are defined on the basis of the moisture profile, a drawing window describing the allowable tension to be directed to the paper web is defined, the lower and upper limits of the drawing window being defined on the basis of the minimum and maximum values for moisture, and the speed difference between the operational groups is adjusted so that the paper web tension is within the range defined by the drawing window.

Abstract: The invention relates to a device for detecting properties of a moving web of paper, more specifically for production control in the paper making process, with an infrared lighting device suited for illuminating the web of paper with infrared light and provided with a light exit portion, with a detector device for detecting infrared light reflected or transmitted by the web of paper which is provided with a light input portion and with a housing a) which is arranged in immediate proximity to the paper web, b) which is provided with a front face facing the web of paper and c) which accommodates the light exit portion and/or the light input portion provided with optical fibers. A plurality of n spherical lenses is arranged in a sealed manner in the front face, said spherical lenses being each optically coupled to an allocated optical fiber within the housing, said spherical lenses constituting, together with the corresponding optical fibers, the light exit portion and/or the light input portion.

Abstract: An infrared detector device for a device for detecting properties of a moving web of paper, more specifically for a device for controlling production in the paper making process, the detector device being provided, on the one side, with a polychromator that receives, on its receiving side, light coming from the web of paper and, on the other side, with an infrared detector with a matrix of infrared sensitive photoconductors, an evaluation electronic unit with one memory assigned to a respective one of the photoconductors of the matrix being connected downstream thereof. An additional source of light that can be controllably switched on and off between a first light intensity and a second light intensity which is greater than the first one uniformly illuminates the infrared detector for deriving correction values for correcting the signals from each of the photoconductors during a measurement.

Abstract: A method and an arrangement for keeping a measuring device clean, the measuring device being arranged to measure at least one property of a moving web and comprising at least one measuring head with at least one measuring element that is cleaned with cleaning agent during measurement.

Abstract: The invention relates to an actuator comprising a motor (4) by which the shafts (1, 5, 7) of the actuator are driven. At least one magnet (20 is arranged in conjunction with the shaft (1, 5, 7). The actuator further comprises at least one Hall sensor (3), which generates pulses as the magnet (2) on the shaft (1, 5, 7) passes the Hall sensor (3) as the shaft (1, 5, 7) rotates. The pulses are used to define the position of the actuator in the linear direction.