Abstract: Apparatus for washing and dewatering pulp and a system for controlling this apparatus are provided. The apparatus includes a pair of rotatable press rolls installed in vats and including a press nip therebetween, an inlet for feeding the pulp to the press nip, with one of the press rolls being movable in relation to the other and in which the processing of the pulp is determined by the number of variable operating parameters. The system includes apparatus for utilizing the distance between the press rolls as a variable operating parameter, for setting a desired value for a specific control parameter, for measuring the specific control parameter, and for adjusting at least two of the variable operating parameters during operation to maintain the difference between the desired value and the measured value of the specific control parameter below a predetermined difference.

Abstract: Apparatus for washing and dewatering pump comprising a pair of rotatable press rolls with permeable outer surfaces, a casing comprising a vat in which the rolls are installed, and a feed for feeding the pulp to the gap formed between the vat and the press roll is disclosed. The vat includes a first side vat segment partially enclosing the first press roll and a second side vat segment partially enclosing the second press roll and casing members for each of the vat segments, the first casing member being pivotable about an axis of rotation and between closed and open positions, pulp distribution devices for distributing pulp onto the press rolls, at least one of the pulp distribution devices being mounted on the casing member whereby it is moved away from the press roll together with the casing member when it is opened.

Abstract: A method of mixing paper stock, having improved outlet consistency, includes: (a) feeding liquid and feeding paper pulp into a vessel to form a mixture; (b) providing at least one counterflow impeller that is submerged in the mixture, the counterflow impeller being capable of simultaneously inducing both upward flow and downward flow; (c) rotating the counterflow impeller such that downward flow from the impeller is partially recirculated by upward flow from the impeller to form a mixing zone; (d) sensing a parameter of the mixture discharged from the vessel; and (e) controlling the feed rate of the liquid and the feed rate of the paper pulp in the feeding step (a) based on the sensing step (d). An apparatus for mixing of paper stock, having improved outlet consistency, includes a vessel for containing liquid and paper pulp, at least one counterflow impeller, and a feedback system for controlling outlet consistency.

Abstract: A forming section in a machine for producing a web of fibrous material includes a control and/or regulating system including a control and/or regulating device which is connected with at least one device for at least indirect acquisition of one value at least indirectly characterizing the dry content of the fibrous web in a transfer area from the forming section to a following function unit, with a device for input of a desired value for the target dry content, and with at least the control elements of an individual dewatering unit located prior to one of the last dewatering units, or the last dewatering unit inside the compression zone. The control and/or regulating device also includes a device for creating the control variables for controlling the individual dewatering units.

Abstract: A forming section in a machine for producing a web of fibrous material includes a control and/or regulating system including a control and/or regulating device which is connected with at least one device for at least indirect acquisition of one value at least indirectly characterizing the dry content of the fibrous web in a transfer area from the forming section to a following function unit, with a device for input of a desired value for the target dry content, and with at least the control elements of an individual dewatering unit located prior to one of the last dewatering units, or the last dewatering unit inside the compression zone. The control and/or regulating device also includes a device for creating the control variables for controlling the individual dewatering units.

Abstract: A chemical or chemical compound (L) is supplied via at least two displacement pumps (1, 4) to a common supply line (11), through which the chemical or chemical compound (L) is supplied to the operating device (12) of a fibrous web machine. Each pump (1, 4) has a corresponding electric actuator (2, 5) which is equipped with a corresponding control drive (3, 6). The fibrous web machine has a measuring device (8; 8a, 8b) for determining the phase angles of at least the first and second actuators (2,5). A control signal based on the determined phase angle information is formed and transmitted to the first control drive (3), based on the control signal, the difference between the first and second electric actuators (2, 5) is adjusted. An electric synchronization signal between the control drives (3, 6) maintains the difference between the phase angles electric actuators (2, 5).

Abstract: This invention relates to a system and a method for optimization of the process performance of a web-processing machine, in particular a machine for the production or further processing of paper, paperboard or tissue, including the following steps: storage of specific data of a component on a data storage unit fitted to the component; and/or measurement of relevant properties of the component by way of a sensor unit fitted to the component; sending of the specific data and/or the measured relevant properties to an open-loop control unit and/or a closed-loop control unit; and optimization of the process performance by way of the open-loop control unit and/or the closed-loop control unit using specific data and/or the measured properties of the component.

Abstract: Methods for processing pulp in an apparatus for washing and dewatering pulp and a system for controlling this apparatus are provided. The apparatus includes a pair of rotatable press rolls installed in vats and including a press nip therebetween, an inlet for feeding the pulp to the press nip, with one of the press rolls being movable in relation to the other and in which the processing of the pulp is determined by the number of variable operating parameters. The method includes utilizing the distance between the press rolls as a variable operating parameter, setting a desired value for a specific control parameter, measuring the specific control parameter, and adjusting at least two of the variable operating parameters during operation to maintain the difference between the desired value and the measured value of the specific control parameter below a predetermined difference. Systems for controlling this apparatus are also disclosed.

Abstract: The invention relates to a method in the manufacture of a fiber-based web-like product for optimizing the operation of the process being used, in which method quality factors are defined for the product being manufactured control variables, which affect the state of the process, or quality factors of the finished product, are defined for at least part of the process. In addition, an operating model is created, which is used to depict the effect of each control variable on the quality factors, and a user interface is created, through which varying values for the control variables can be input to the operating model and the values of the quality factors can be depicted simultaneously, in such a way that the values of the control variables and the values of the quality factors can be viewed simultaneously.

Abstract: This invention relates to a dewatering apparatus, in particular a paper machine or a paperboard machine, for the adjustable, and controllable dewatering of a fibrous material, which is conveyed as a fibrous web that can be divided into at least two zones arranged side by side in a cross direction (CD). The dewatering apparatus is characterized in that the dewatering of the fibrous material is adaptable to a dewatering curve defined in a machine direction on the basis of measurements of the water weight of the fibrous material taken by at least two water weight sensors, in particular a one-dimensional or multi-dimensional sensor arrangement of water weight sensors, which are assigned to a zone and arranged preferably in pairs in mutually offset position in the CD direction.

Abstract: A method and arrangement for controlling short circulation in a paper machine, in which the control of at least one property of the diluted fiber-containing pulp conducted to the headbox is based on consistency measurement or determination in high-consistency fiber-containing pulp, diluted pulp and/or white water. The amount of fiber-based fines in high-consistency fiber-based pulp, diluted fiber-based pulp and/or white water is determined, and the result obtained is used for controlling at least one property of the fiber-containing pulp to be conveyed to the headbox.

Abstract: In a method for the production of a fibrous web, especially a paper or cardboard web, an automatic ash control system and an automatic retention control system for the reduction or suppression of an interactive build-up of the two controls are linked via a model for the dependence between the filler addition and the retention agent consumption. A computer assisted quality control system is also cited.

Abstract: A method and apparatus for treating pulp in connection with a blow tank or a storage tank. The pulp is discharged from a batch digester and fed either to the upper or the lower part of a blow tank, depending on the consistency of the pulp being discharged from the digester.

Abstract: Adjusting the operation of a wire section, in which the development of the consistency of stock on the wire section (2) is determined and the effect of the consistency determined above on the formation and/or porosity of a paper web (3) 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.

Abstract: In a paper machine which comprises process elements and a measuring beam, the measuring beam is arranged at least at one paper machine process element so that a measuring device for measuring quality properties of a paper web is arrangeable in the measuring beam. The paper machine process element is e.g. a blow box, which is arrangeable in a dryer unit of the paper machine between drying cylinders to blow air via at least one blow air channel provided in the blow box to guide the moving paper web and/or to assist drying.

Abstract: Paper quality is controlled in the production of a paper web, where paper stock is fed from the headbox of the paper machine onto the wire section, whereby the paper stock is formed into a paper web. The headbox flow rate and consistency are measured from the paper stock fed into the headbox, and the water quantities removed on the wire section during the formation of the paper web are measured on the wire section. In the method, a filler distribution model is established, into which data on the wire section geometry, measured headbox flow rate and consistency and on the water quantities removed on the wire section are entered, and the model is used for establishing an estimate of the filler distribution, and the running values of the paper machine are adjusted on the basis of the estimated filler distribution.

Abstract: A method and apparatus for treating pulp being fed into a blow tank or a storage tank. A preferred embodiment is that the pulp is discharged from a batch digester (10) and fed either to the upper or lower part of a blow tank (20), depending on the consistency of the pulp being discharged from the digester.

Abstract: Headbox for one of a paper and cardboard machine includes at least one material suspension supply running a width of the machine. At least one turbulence producer has at least one conduit through which a material suspension flows. At least one metered addition point is located in the conduit for introducing a fluid medium. A headbox nozzle is located downstream from the at least one turbulence producer for delivering the material suspension. A portion of a flow resistance located downstream of the metered addition point is at least approximately 50% of a total flow resistance of the at least one conduit.

Abstract: A method for producing and testing a fiber bed, includes a housing, a main inlet passage and a main outlet passage, a cavity in the housing in fluid connection with the inlet and outlet passages, a body rotatably arranged in the cavity, the body being arranged with a through-going passage having first and a second opening, a screen arranged in the through-going passage, and elements for measuring properties of the fiber bed. The method includes positioning the body so that the first opening is connected to the main inlet and the second opening is connected to the main outlet, creating a first passage, leading a fiber suspension through the first passage in order to produce a fiber bed on the screen, measuring the properties of the bed, rotating the body such that the second opening is connected to the main inlet and the first opening is connected to the main outlet and creating a flow through the first passage for removing the fiber bed from the screen through the outlet.

Abstract: A method and an apparatus for mixing dilution liquid into a stock flow in a paper or board machine. Dilution is carried out in at least two stages using in the first dilution stage (I) valves (V1, V2, V3 . . . ) fitted with a larger mutual spacing at different points of width across a headbox and passing the dilution water through the valves to desired points of width of the headbox according to the requirement of control of the basis weight of paper or board. In the second dilution stage (II), dilution water is passed into connection with the stock flow coming from the first dilution stage (I), said dilution water being controlled by means of valves (V1′, V2′ . . . ), which valves (V1′, V2′ . . . ) have been fitted with a denser spacing than the valves (V1, V2, V3 . . . ) of the first dilution stage (I).

Abstract: A system and method for monitoring and control operation of a rotary disk refiner. The method regulates refiner operation in response to a process variable preferably in relation to a setpoint. The variable can be temperature, pressure, and/or stock consistency, refiner energy, or a variable based thereon. Volumetric flow rate of stock and/or the flow rate of dilution water can be regulated. Based on a refiner temperature, pressure, and/or stock consistency, refiner energy, or a variable based thereon, the flow rate of stock and/or dilution water can be regulated. Where temperature is used, it preferably can be a temperature inside the refiner or adjacent the inlet or outlet. Where pressure is used, it preferably can be a pressure inside the refiner or adjacent the inlet or outlet. Stock consistency can be determined using a sensor upstream or downstream of the refiner or using a sensed parameter in the refiner.

Abstract: A method of selecting bulk wood units for mechanical pulping, which consists of establishing a reference scale by selecting a test sample measuring the acoustic velocity through each sample unit, selecting acoustic velocity band from the sample results, processing the sample units using known mechanical pulping processes, testing the resulting pulp to measure the freeness of the pulp, and then graphing the pulping energy measurements against the pulp freeness measurements for each of the velocity bands to produce a reference scale; measuring the acoustic velocity through each of the units, comparing the velocity measurement for each unit against the reference scale, and then dividing the tested units into subgroups according to the predicted mechanical pulping energy.

Abstract: A headbox (10) has a stock inlet header, a tube bank, a tubulence generator and a slice channel. Measurement targets (PA, PB, PC, P, PE) are provided with means for making measurements of the fiber mobility of the fiber suspension, then controlling the flow state of the suspension. Sensors on the width of the headbox (10) or traversing sensors are positioned on different width points of the headbox (10) and arranged to measure the fiber mobility profile, with means for changing the flow state on the basis of the measurements. Apparatus for diluting the thick stock into headbox consistency and units for cleaning the stock to be fed into the headbox may be provided. Sensors may be disposed in the short circulation pipes or cleaning units arranged to measure the fiber mobility of the fiber suspension with means for changing the flow state on the basis of the measurement data.

Abstract: A multi-layer headbox for a paper or board machine including stock inlet headers each providing one stock and coupled to a tube bank which in turn is coupled to a respective intermediate chamber. The stock flows from the intermediate chambers into a turbulence generator and through pipes in the turbulence generator into a slice cone to be discharged therefrom onto a forming wire. The multi-layer headbox includes distribution valves for regulating the flow of dilution water across the width of the headbox. Each distribution valve communicates with a distribution plate placed in connection with the tube bank. From each valve, the dilution liquid is distributed at the same time to all the stocks that form the different layers of the web in the multi-layer headbox at a specific position of width of the multi-layer headbox.

Abstract: Process and a device for detecting a change in the fiber orientation cross-direction profile of a paper or cardboard web in the manufacturing process on a paper or cardboard machine. It is recognized that a change in the fiber orientation cross-direction profile in the web is inferred or determined by way of a characteristic change in the basis weight cross-direction profile or at least one measurement quantity that correlates to it, and/or by way of a characteristic change in the basis weight in the travel direction of the web or at least one measurement quantity that correlates to it. The device includes an arrangement for detecting a change in the basis weight cross-direction profile and/or a characteristic chronological course of the change in the basis weight, which is characteristic for a change in the fiber orientation.

Abstract: The invention concerns the short circulation of a paper or board machine and in particular a simplified process arrangement for the short circulation, which arrangement comprises a metering system (20) for the stock (M) or stocks, pumps (110, 130, 170), a headbox (150), and a wire part (160) as well as a pipe system interconnecting the devices, with means of regulation, and in which arrangement a high-consistency stock (3) is fed into the headbox (150), and the white water (4) recovered from the wire part (160) is fed by means of a diluting pump (170) into the headbox (150) so that diluting of the stock suspension is carried out in the headbox.

Abstract: Process for a metered addition of a fluid medium into a material suspension stream of a headbox, including feeding the material suspension in a main flow direction through at least one turbulence-producing conduit to a headbox nozzle, the at least one turbulence-producing conduit having an entrance, a graduated pressure loss area, and an exit. A total pressure loss &Dgr;Ptotal is caused in the at least one turbulence-producing conduit such that the total pressure loss &Dgr;Ptotal includes at least one intake pressure loss &Dgr;Pintake formed at the entrance and a graduated pressure loss &Dgr;Pgrad formed at the graduated pressure loss area. A metered addition of a fluid medium is also provided in a region between the entrance and the exit.

Abstract: The stock approach piping to a multi-layered headbox can be modified to include a dilution water header that independently supplies dilution water, such as whitewater, to multiple CD segments or zones of the tube bank which supply stock to each layer. The CD basis weight profile of the final sheet is monitored and, in response to the measured CD profile, dilution water flow is increased or decreased to those tube bank segments that need their consistency altered. By selectively controlling the basis weight of distinct segments of the CD profile for each layer, a more uniform sheet can be produced.

Abstract: The present invention relates to a method for producing and testing a fiber bed (39), includes a housing (12), a main inlet passage (14) and a main outlet passage (16), a cavity (18) in said housing in fluid connection with said inlet and outlet passages, a body (20) rotatably arranged in said cavity, said body being arranged with a through-going passage (24) having a first and a second opening, a screen (25) arranged in said through-going passage, and means (40) for measuring properties of the fiber bed.

Abstract: The invention concerns a headbox for a paper/board machine by whose means the basis weight of the web can be regulated. The headbox comprises a stock inlet header (Jl), which becomes narrower towards its end. Tubes (11a1, 11a2 . . . ) in a tube bank (11) open in the stock inlet header (J1) across the machine width, which tubes are connected with thickening elements (12a1, 12a2 . . . ) across the machine width, in which connection a flow (L1) is removed from the thickening element into the duct (D1) and said flow (L1) to be removed is regulated by means of a valve (V1, V2 . . . ). From the thickening element (12a1, 12a2 . . . ) a tube (14a1, 14a2 . . . ) for a flow (L2) of higher consistency is provided, which flow is passed further in the headbox.

Abstract: The invention concerns the short circulation of a paper or board machine and in particular a simplified process arrangement for the short circulation, which arrangement comprises a metering system (20) for the stock (M) or stocks, pumps (110, 130, 170), a headbox (150), and a wire part (160) as well as a pipe system interconnecting the devices, with means of regulation, and in which arrangement a high-consistency stock (3) is fed into the headbox (150), and the white water (4) recovered from the wire part (160) is fed by means of a diluting pump (170) into the headbox (150) so that diluting of the stock suspension is carried out in the headbox.

Abstract: The invention relates to a headbox (10) for a paper/boardmaking machine. The headbox (10) including a stock flow header (11) and, following the stock flow header, a piping system such as an inlet pipe manifold, and/or a turbulence generator (14) and a tapered slice (15), wherefrom the stock is passed onto the forming wire (H1). The construction of said headbox further includes a flow header (J) for a dilution liquid the flow header having connected thereto an inlet channel (S1), a return pipe (S2) and outlet channels (D1, D2, D3, . . . ) that are distributed over the full length of said flow channel for passing the dilution water to control valves (V1, V2, . . . ) and, therefrom, further to different points along the cross-machine width of the headbox so as to mix with the stock delivered from the stock flow header (11) in order to control the consistency of the stock to a desired value, thus accomplishing the control of the web basis weight profile in cross-machine direction over the headbox.

Abstract: Paper or cardboard machine and method for regulating a basis weight of a paper or cardboard web in the manufacturing process. The paper or cardboard machine includes at least one headbox that extends across a machine width. The at least one headbox is adapted to provide a machine-wide distribution of a material suspension onto one of a screen and between two screens. The machine also includes at least one material suspension supply coupled to the at least one headbox and adapted to supply a material suspension to the at least one headbox. The at least one material suspension supply has at least one concentration.

Abstract: Method and apparatus for controlling the mixing proportions of feed streams being supplied to a headbox, using devices for sampling two or more of the feed streams upstream of the headbox and devices for measuring concentration of constituents in or other properties of those samples. A method of regulating one or more properties of a moving web, and especially a paper web during manufacture, employing the aforesaid method and apparatus are also disclosed.

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).

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).

Abstract: A multi-layer headbox for a paper or board machine including stock inlet headers each providing one stock and coupled to a tube bank which in turn is coupled to a respective intermediate chamber. The stock flows from the intermediate chambers into a turbulence generator and through pipes in the turbulence generator into a slice cone to be discharged therefrom onto a forming wire. The multi-layer headbox includes distribution valves for regulating the flow of dilution water across the width of the headbox. Each distribution valve communicates with a distribution plate placed in connection with the tube bank. From each valve, the dilution liquid is distributed at the same time to all the stocks that form the different layers of the web in the multi-layer headbox at a specific position of width of the multi-layer headbox.

Abstract: Process and apparatus for improving a consistency cross-direction profile of a fiber web in the wet section. The process includes distributing a fiber suspension across a machine width from a headbox to one of on a wire and between two wires, adjusting a cross-sectional basis weight by sectionally mixing, across the machine width, a first suspension having a first solid content and a first percentage composition and a second suspension having second solid content that is one of lower and higher than the first solid content, and a second percentage composition of the solids content of the second suspension differs from the first percentage composition, and sectionally admixing at least a third suspension across the machine width, the third suspension having a solids content that is one of lower and higher than the solids content of at least one of the first and second solids content, and having a third percentage composition that differs from at least one of the first and second percentage compositions.

Abstract: A paper machine for making a fiber web includes an approach flow system with a plurality of control modules. Each control module controls one of a plurality of adjustable input parameters. A wet end receives a fiber suspension from the approach flow system, and includes a headbox which discharges a fiber suspension with a known cross sectional profile onto a wire. A press section, forming section and drying section are used to press form and dry the fiber web, respectively. A plurality of sensors are respectively positioned in association with the approach flow system, wet end, press section, forming section and/or drying section. Each sensor is configured to sense a physical characteristic of the fiber suspension or fiber web and provide an output signal indicative thereof. A chemistry process controller is coupled with each sensor and each control module within the approach flow system to define a closed loop control system. The chemistry process controller controls operation of each control module.

Abstract: A method and apparatus for producing calendered paper by an on-line manufacturing system comprising at least a paper machine and a multi-nip calender. The method comprises following steps: removing water from a formed paper web by pressing, drying the pressed paper web by at least one dryer, calendering the dried web by the multi-nip calender, measuring a cross-machine moisture profile or a variable relative thereto, and altering the moisture of the web so that the moisture profile of the web in the cross-direction is even when the web enters the first nip of the calender.

Abstract: Process for controlling and consistency-controlled headbox for a paper machine with a common feed line for a pulp slurry, a plurality of feed line sections into which the common feed line branches, and a system for influencing the composition of the slurry flows in each of the plurality of feed line sections. At least one pulp consistency sensor is provided for sectional pulp consistency control.

Abstract: Method for regulating the basis weight of paper or board in a paper or board machine in which the machine stock is comprised of a number of component stocks and the basis weight of the dry paper or board is measured, preferably by on-line basis-weight measurement at the end of the machine. Based on the stock target of the machine stock formed on the basis of basis-weight regulation and the predetermined stock proportions of the component stocks, a metering target is determined for each component stock. Then, based on the consistency of a component stock measured from each feed line of a component stock and on a metering target determined for each component stock, a flow target is determined for each component stock. Finally, the flow of each component stock is regulated based on the flow target determined for each component stock.

Abstract: Process for setting a uniform characteristic cross-direction profile for a paper web with regard to at least formation, basis weight, and fiber orientation in a paper machine. The paper machine can include a headbox with an adjustable die exit opening and within which the consistency is sectionally adjustable. The process includes measuring and setting a desired basis weight cross-direction profile by adjusting the sectional consistency in the headbox, adjusting the formation cross-direction profile by adjusting a sectional, specific pulp slurry flow rate at the die exit opening, and one of enlarging the die exit opening at positions along a width of the paper machine in which a pulp slurry flow rate is higher than in other positions along the width of the paper machine and increasing the pulp slurry flow rate for positions along the width at which the die exit opening is larger than at other positions along the width. In this manner, a desired fiber orientation cross-direction profile is attained.

Abstract: The invention relates to an apparatus and a process for feeding papermaking stock to a papermachine. The apparatus comprises a mixing vessel (12) for receiving and mixing stock components and a pipe (40) for feeding the resulting mixed stock to said papermachine. In the feeding pipe (40) there are stock flow metering means (42) stock consistency sensing means (44) and stock flow control means (32). Said means are all connected to a control system (46) adapted for receiving said flow data (Q) and said consistency data (C). The control system (46) is adapted for continuously computing a value for the product (Q×C) of said flow and consistency and for providing adjustment of the flow control means (32) to keep said product (Q×C) at a target value. The invention provides faster response times in the control of a papermaking process. It also reduces the volume of stock mixing vessels and the amount of water in the process.

Abstract: The stock approach piping to a multi-layered headbox can be modified to include a dilution water header that independently supplies dilution water, such as whitewater, to multiple CD segments or zones of the tube bank which supply stock to each layer. The CD basis weight profile of the final sheet is monitored and, in response to the measured CD profile, dilution water flow is increased or decreased to those tube bank segments that need their consistency altered. By selectively controlling the basis weight of distinct segments of the CD profile for each layer, a more uniform sheet can be produced.

Abstract: Process and a device for detecting a change in the fiber orientation cross-direction profile of a paper or cardboard web in the manufacturing process on a paper or cardboard machine. It is recognized that a change in the fiber orientation cross-direction profile in the web is inferred or determined by way of a characteristic change in the basis weight cross-direction profile or at least one measurement quantity that correlates to it, and/or by way of a characteristic change in the basis weight in the travel direction of the web or at least one measurement quantity that correlates to it. The device includes an arrangement for detecting a change in the basis weight cross-direction profile and/or a characteristic chronological course of the change in the basis weight, which is characteristic for a change in the fiber orientation.

Abstract: A system and method of providing on-line turbulence measurements in a sheetmaking machine and using these measurements to perform on-line adjustments to turbulence-inducing and adjusting elements in the sheetmaking machine to optimize final sheet product quality. Turbulence measurements are obtained using water weight sensors in the wet-end of the sheetmaking machine and specifically under wire water weight measurements. Water weight readings are correlated to turbulence intensity levels by correlating ranges of water weights to intensity level intervals. A turbulence processing sensor sorts accumulated water weight measurement readings into intensity level intervals to obtain turbulence measurements or a turbulence profile. The turbulence measurements or profile is provided to a machine element controller which uses the measured turbulence information and target turbulence information to generate control signals.

Abstract: A headbox for a paper machine which mixes suspension and additives to achieve a selected basis weight cross direction profile and fiber orientation cross direction profile in paper produced from the machine. The headbox has sections across its width. Each section is supplied with a first stream Q.sub.H of one suspension component, a second stream Q.sub.L of a second suspension component. A valve regulates the total suspension flow Q.sub.M as well as the ratio between the first and second streams. An additive stream Q.sub.ad for each section communicates into the combined suspension flow. A valve regulates the additive stream for achieving the selected profiles. Various places along the suspension flow path are indicated as inlets for the additive stream. The headbox has a microturbulence generator for generating turbulence in the suspension passing through it. There may be lamellae within the headbox which somewhat separate the entry flow into the headbox.

Abstract: Significant improvements in papermaking control can be achieved by employing an array of sensors that are positioned underneath the wire of the machine to measure the conductivity of the aqueous wet stock. The conductivity of the wet stock is directly proportional to the total water weight within the wet stock; consequently, the sensor provides information which can be used to monitor and control the quality of the paper sheet produced. Because CD water weight profile is obtained practically instantaneously, the MD and CD variations are essentially decoupled. Quality improvements to the sheet fabricated will be achieved by providing fast control of the actuators on the machine and by tuning components on the machine to eliminate the sources of variations.

Abstract: A dilution control device interconnects a tapered header with a turbulence generator in a paper-making machine. The turbulence generator includes a substantially planar inlet surface and a plurality of fluid passages, with each fluid passage having an inlet at the inlet surface. The tapered header includes a header plate with a plurality of outlets therein, with each outlet being associated with at least one inlet of the turbulence generator. A dilution module block is positioned between and interconnects the header plate with the inlet surface of the turbulence generator. The dilution module block includes a plurality of through holes and a plurality of feed channels. Each through hole interconnects an outlet of the tapered header with at least one inlet of the turbulence generator. Each feed channel is in fluid communication with at least one through hole and is configured for transporting dilution water to a corresponding through hole.