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: 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 system and method of providing fast machine direction (MD) and cross direction (CD) basis weight adjustments using a simultaneous multi-point water weight sensor which provides independent MD and CD measurements is described. The water weight sensor is placed under the wire of the sheetmaking machine and provides fast wet end water weight measurements which are converted into predicted dry end basis weight information and used to control operating variables of machine elements in the sheetmaking machine to compensate for high frequency process variations. MD wet end measurements are used to control operating variables of machine elements that influence the MD dry end basis weight and CD wet end measurements are used to control operating variables of machine elements that influence CD dry end basis weight.

Abstract: 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, which may be located in a return portion of the pulp distributing line. A weight basis cross-sectional adjustment sensor and controller may also be used; with the pulp consistency controller arranged to operate with a significantly higher sensing rate than the weight basis cross-sectional adjustment controller.

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 system for applying a suspension of uncooked starch particles in water to a web on a forming wire includes a source of such suspension and a source of dilution water, an application die positioned transversely of the web with an internal manifold opening into a downwardly opening die slot through which material flows from the manifold as a falling curtain onto the web. The die has a plurality of transversely spaced inlets leading into the manifold to define transversely spaced application zones across the web. The suspended starch and water are applied from the manifolds through control valves into the inlets by means of which the consistency or concentration of the starch may be varied at positions representing the application zones across the web to provide a desired strength profile to the dried web.

Abstract: Apparatus for influencing a cross-sectional profile of a headbox having an inner chamber and process for determining a width and position for the sections of the headbox. The apparatus includes a device for distributing fluid that extends across a machine width, at least one connection opening extending across the machine width between the fluid distribution device and the inner chamber of the headbox, and a plurality of elements being one of continuously and discretely adjustably positionable within the fluid distributing device to section the fluid distributing device across the machine width. The process includes measuring a profile of a selected characteristic of the pulp suspension in the headbox that is dependent on its position; forming intersecting points of the profile of the characteristic with a uniform sectioning of the size of the characteristic under consideration; and determining the position and width of the sections.

Abstract: An apparatus for sensing three properties of materials: the conductivity or resistance, the dielectric constant, and the proximity of the material to the sensor portion of the apparatus. The apparatus includes a fixed impedance element coupled in series with the sensor portion of the apparatus between an input signal and ground. The sensor portion of the apparatus is an electrode configuration which includes at least two electrodes with a portion of the material residing between and in close proximity to the electrodes. The sensor exhibits a variable impedance resulting from changes in physical characteristics of the material. The fixed impedance element and the variable impedance of the sensor portion form a voltage divider network such that changes in impedance of the sensor portion results in changes in voltage on the output of the apparatus.

Abstract: Apparatus and process for controlling the basis weight of paper produced in a papermaking machine are provided. In the papermaking process, a major portion of the paper stock flows through a first line that is controlled by a thick stock valve and a minor portion of the stock flow from the stuff box to the headbox is diverted through a second line that is regulated by a second valve (e.g., vernier valve). The thick stock valve is controlled by the dry end basis weight and the second valve responsive to measurements of the basis weight of the wet stock at the wire. The second line and control valve along with the wet end basis weight measurements form a fine control loop with fast response time whereas the first line and control valve that is responsive to dry end basis weight measurements form a course control loop. The dual control loops enable fast and actual basis weight control.

Abstract: A regulation system and method in a paper machine for controlling the variation of the basis weight of a paper web in the machine direction in which the basis weight profile of the web is measured by means of a measurement device and a basis weight regulation system receives a signal of the measurement of the basis weight from the measurement device and generates a regulation signal for controlling the flow of thick stock passed into a short circulation circuit in the paper machine by a basis weight valve and/or a regulation pump. The variation of the basis weight in the machine direction in the paper machine is controlled, besides by the short circulation circuit of regulation, also by a substantially faster second circuit of regulation which comprises one or more actuators for controlling the flow rate of the dilution water flow in the dilution profiling system of the headbox and/or the consistency of the dilution water flow across the entire width of the paper web.

Abstract: A system and method that combine an array of fast under wire water weigh sensors with a scanning system provides an accurate measurement of the entire sheet down to 1 in. by 1 in. resolution. Because CD profiles are obtained instantaneously, MD and CD variations are completely decoupled, even if CD profiles are taken at longer intervals apart.

Abstract: The present invention is directed to a method for controlling and adjusting the permeability of a cigarette wrapping paper. Permeability is controlled in the paper by adding different sized filler particles in different proportionate amounts. Permeability of the paper is altered without having to change the total amount of filler in the paper. By selectively controlling the permeability of the paper, various characteristics and properties of a cigarette made with the paper can be likewise modified as desired. In one embodiment of the present invention, the permeability of a cigarette wrapper can be automatically maintained or adjusted as the paper is being made.

Abstract: A method of predicting the dry stock weight of paper that is produced by a papermaking machine based on simultaneousness measurements of (1) the water weight of the paper stock on the fabric or wire of the papermaking machine and of (2) the dry stock weight of the paper product is provided. The invention which provides a linearized model of the de-watering process is based in part on that creation of drainage characteristic curves that provides an effective means of predicting the drainage behavior of the paper stock on the fabric of a de-watering system.

Abstract: A method for regulation of the transverse distribution of the fiber orientation of a web produced by means of a paper machine or equivalent, by regulating the transverse profile of the discharge opening (16) of the headbox (10) of the paper machine. The transverse grammage profile of the paper web (W.sub.0 . . . W.sub.1) produced by means of the paper machine is measured, and the measurement signal obtained in this way is used as a feedback signal in the control system. With the machine configuration and parameters present in the paper machine to be controlled, data are collected concerning the relationship between the directional angle of the transverse distribution of fiber orientation and the transverse distribution of grammage of the web (W.sub.0 . . . W.sub.1) that is being produced by, carrying out response runs of the paper machine in its various states of operation (i). The relation data are stored in the memory of the computer (52).

Abstract: Process for damping pressure pulsations and apparatus for performing the process. The process of this invention serves for the damping of pressure pulsations in a fluid, particularly a fiber suspension, flowing in a closed system wherein the pressure pulsations to be damped are measured at a measuring site and compensated at a correction site, with a throttle position being located between the measuring and the correction sites, with the damping of the imparted pressure impulses occurring at the correction site, which pressure impulses are opposite to the measured pressure pulsations, with the time periods thereof being about the same as those of the measured pressure pulsations. Several apparatuses for performing the process are also set forth.

Abstract: A multilayer headbox for the introduction of at least two fiber suspension streams to the forming section of a paper manufacturing machine includes a nozzle chamber further defined by two stream guide walls which end at an outlet gap and by two side walls. At least one lamella is provided in the nozzle chamber, this lamella keeping at least two fiber suspension streams separated from each other through the region of the outlet gap. The lamella includes a body, preferably made of plastic, and a tip made of a hard material. The tip is either a strip or a coating having a sharp tip-edge integrated into the body of the lamella.

Abstract: This invention relates to the measurement and control of consistency in an aqueous flow stream, as it leaves a stage (i.e. Bleaching Stage) of the papermaking process. More particularly, the present invention relates to the measurement used for control of wood fiber and suspended solids in a papermaking pulp stock flow stream.

Abstract: A multilayer headbox of a paper machine for producing a paper web with several layers having different properties, and an appropriate method therefor. In at least one first layer there is adjusted alone the fiber orientation cross profile and in at least one second layer there is adjusted alone the basis weight cross profile.

Abstract: A method and apparatus for lateral alignment of a cross-direction profile control of a web as required in a paper-making process. In the method, a certain cross-direction profile of a dried web, particularly the basis weight profile thereof, to be aligned is gauged. A profile measurement signal thus obtained is passed to a control system of the paper machine which provides a control signal suited to control adjustment devices of the cross-direction profile control provision. The web is provided with at least one marker line whose lateral shift or shifts is/are detected at the measurement point of the cross-direction profile of the dried web, or in the vicinity thereof. The detection of the lateral shift(s) is used to generate a measurement signal thereof which is employed to control the lateral alignment of the web profile adjustment provision.

Abstract: The invention is directed to a roll shake connected to a roll in a paper-making machine, wherein the roll is movable in a direction generally parallel to an axis of the roll. A first hydraulic ram assembly, including a first cylinder and a first ram reciprocally disposed in the first cylinder, is attached to the roll. A second hydraulic ram assembly, including a second cylinder and a second ram reciprocally disposed in the second cylinder, is rigidly connected to the first cylinder. A counter mass is connected to the second ram, and is movable in a direction generally parallel to the roll axis. A controller is connected to the first hydraulic ram assembly and the second hydraulic ram assembly. The controller independently controls reciprocating movements of the first ram and the second ram within the first cylinder and the second cylinder, respectively, whereby a resultant momentum of the roll and the counter mass is approximately equal to zero at any point in time.

Abstract: A pulp furnish containing predominantly wood-containing fibers (mechanical) and natural calcium carbonate as a filler is formed into a paper in a paper forming section of a paper machine at a neutral pH in the range of 6.7 to 7.5. Bentonite plus a suitable polymer such as a polyacrylamide produces a pulp stock that has exceptionally high drainage characteristics particularly when used with chalk as the filler. The pH of the stock in the headbox is maintained at the desired level of pH 6.7-7.3 by monitoring the pH in the headbox and adjusting the flow of pH reducing and buffering agent, preferably phosphoric acid, into the pulp prior to the headbox to obtain the desired pH in the stock.

Abstract: The system effects an automatic observation of the dry line on wire of the Fourdrinier paper machine and the control actions based on it. In order to produce an image of the dry line range on wire this is illuminated by means of a large, diffusely illuminating surface (20) of even luminosity. The material on moving wire (10) is imaged by an optoelectric camera (40) on a detector whereby the pulp surface preceding the dry line and being specularly reflecting is found homogeneous and bright while the web surface following it and being diffusely reflecting is found homogeneous but matter and darker. The electric image signal delivered by the detector is conducted to a computer (50) in which the dry line is identified as the borderline of said surfaces of different brightness.

Abstract: A method of manufacturing a web of fibers, especially a web of paper. The pulp is uniformly distributed through an outlet over the width of the machine and along a wire or between two wires. Most of the moisture is subsequently extracted from the pulp accommodated on or between the wires at a draining point. Various amounts of retaining agents are added to the pulp at sections across the headbox and the web in order to control the level of retention sectionally.

Abstract: A procedure and apparatus for locating faults in the machine elements of a paper machine and in their functioning, wherein variations in the paper characteristics are continuously observed, the periodicity of the variations is recorded and the periodicity of the variations in the paper characteristics is compared with the periodicity in the functioning of the paper machine's machine elements. The apparatus comprises observation members (1-11) for observing the variations occurring in the paper characteristics; synchronizing pick-ups (43-53) disposed on machine elements (13-22) of the paper machine for observing the periodicity of the functioning of said machine elements; a recording means (40) for recording the periodicity of the variations in paper characteristics and the periodicity in the functioning of the machine elements; and a data processing unit (41) for comparing the periodicity of the variations in paper characteristics and that in the functioning of the machine elements.

Abstract: In the manufacture of stretchable webs such as creped tissue, nonwovens, and the like, in which the web is formed and thereafter wound onto a reel, basis weight control of the web on the reel is accomplished by measuring the speed and basis weight of the web prior to winding the web onto the reel and calculating the basis weight of the web on the reel. In response to this calculated value, either the upstream flow of material or the downstream speed of the web (reel speed) are adjusted to obtain the desired basis weight of the web at the reel.

Abstract: A method of foam forming of paper includes the steps of metering a controlled feed of fiber dispersed in an aqueous liquid into a dewatering device, wherein the consistency of the fiber dispersed in the aqueous liquid input to the dewatering device is between about 0.5 and about 7% by weight. A uniform continuous strand of semi-moist pulp is obtained wherein the consistency of the semi-moist pulp leaving the dewatering device is between about 8 and 30% by weight. A stream of a foamed aqueous admixture is obtained and introduced into a dispersing mixer having shearing action extending substantially throughout a zone substantially athwart the flow path of the uniform continuous strand and the foamed aqueous stream and forming a stream of dispersed fiber bearing aqueous foam. The dispersed fiber bearing aqueous stream is conducted to the inlet of a positive displacement pump.

Abstract: The stack reflectance is predicted from an on-line, wavelength dependent measurement of the sheet reflectance and the on-line measurement of the sheet opacity at a wavelength interval. The stack reflectance Rst is then used to predict and/or control stack color, preferably by using the parameter K/S=(1-Rst.sup.2)/2 Rst where K is the dye absorption coefficient and S is the dye scattering coefficient.

Abstract: The present invention relates to a method of qualitative and quantified monitoring of the instant local physical state of a substantially incompressible fluid material such as a liquid or pasty substance (for instance slurry or pulp) and a device for carrying out this method and the various applications and uses resulting from the working of the method and/or device for the automatic control of said physical state. The invention is also directed to the various equipment and systems provided with at least one such device.

Abstract: A paper weight sensor system is intended for use on a paper-making machine having a headbox with a slice-lip mounted thereon for forming a moving web of material. Plural slice-lip actuators are provided for setting the slice-lip gap to control the amount of material in the web and are mounted on the headbox. Plural stationary optical sensors are located at a first station and extend across the width of the web in a continuous array for detecting the transmissivity of the web in a one-to-one relationship with the slice-lip actuators at an aligned location downstream of each actuator. Each sensor includes plural light detectors therein which are operable to generate a first transmissivity signal representing the transmissivity of the web for discrete regions thereof adjacent each light detector corresponding to a given actuator.

Abstract: The maximum amounts of the retention-influencing variable stock components which can be added are determined as a function of a predetermined degree of flocculation and typical values of the stock suspension with the aid of a mathematical relationship, and control signals for metering retention aids are derived from the amounts so that the greatest possible retention can be achieved without exceeding a set-point for the degree of flocculation.

Abstract: An inert gas such as helium is employed as a tracer gas in a pulp and paper mill to determine the utilization of oxygen by an aqueous cellulosic pulp particularly, as well as other parameters, in an oxygen delignification or extraction in which oxygen is dissolved in the pulp and reacted to solubilize lignins and reduce the requirement for chlorine-based bleaching chemicals.

Abstract: A method of controlling the properties of a paper web across the feed direction, i.e., cross profile, in a paper machine. The cross profile is adjusted in a plurality of setting positions across the web. Proceeding from a measured cross profile and desired cross profile, an optimum correction in the setting positions is calculated, so that the cross profile is brought into agreement with the desired one. At this calculation the circumstance is utilized, such that a disturbance in the stock in a certain setting position results in a corresponding change in the cross profile of the paper web.

Abstract: A method for controlling the addition of cationic additive materials to a paper mill slurry used to neutralize the anionic contaminants in a papermaking process is disclosed which utilizes total organic carbon measurements of samples of the slurry as an indicator of the cationic demand of the paper mill slurry. The method of the present invention discloses the discovery that measurements of the total organic carbon taken from filtered samples of the papermaking slurry correlate very well to cationic demand measurements of a papermaking slurry. Therfore, measurements of the total dissolved organic carbon content may be used to determine the desired addition rate of cationic additives in a more convenient and reliable manner than prior control measures. According to the method of the present invention, monitoring of the papermaking slurry by total organic carbon measurements as a cationic additive control parameter provides improved control of such factors as machine drainage and retention.

Abstract: The invention relates to a method and an apparatus for detecting and counteracting a deformation of the stock discharge gap in a paper machine headbox, which is caused by thermal expansion due to the temperature of the stock and/or the pressure of the stock. This is achieved by ultrasonic transducers located close to the slice opening which obtain measurement results relating to the distance between the roof member and the apron beam member of the headbox. At least two such transducers, one preferably located close to a side wall of the discharge gap and the other preferably located midway between the side walls, give information about a possible difference between the measurement results caused by the deformation. This difference serves as a guide for adjusting the temperature of the apron beam member and/or the roof member in such a way that the deformation is reduced in magnitude or entirely eliminated.

Abstract: Pulp vat apparatus for applying pulp to a plurality of conductors in which a pulp vat has a cylinder mould with axially spaced annular perforate regions, one for each conductor, and the vat is divided by partitions into compartments, one for each perforate region. There is a flow inlet for pulp into each compartment and means to vary the pulp flow rate through each inlet independently of the flow rate through the other inlets whereby the level of pulp in each compartment is variable independently of the other compartments.

Abstract: A method and apparatus used in the uniform drying of a continuous web, such as a sheet of paper or paperboard. A newly formed web of paper of wet cellulosic fibers and the necessary additives is initially directed through a press section where excessive water is squeezed from the web to reduce its moisture content to about 50-80 percent, by weight, for subsequent passage through a dryer section wherein the moisture content is further reduced to anywhere between 3 and 15 percent, depending on the quality of the paper being processed. The moisture content profile of the nearly dry web of paper is constantly monitored adjacent the discharge end of the dryer section for dry streaks which occasionally occur in the web. Moisture is added accordingly to the web when the web is relatively wet and has a moisture content of at least 25 percent to eliminate further dry streaks and provides a paper product which has a uniform moisture content.

Abstract: A system for the control of a paper machine headbox having sensors for the measurement of the parameters of the process and actuators of the members of the process, functionally connecting at least most of the sensors to an at least equal number of actuators via a multivariable centralized control member which makes it possible to control each actuator by the taking into account and processing of the measurement information of one or more sensors, and causing the measurement information to act on each of the sensors functionally connected to the actuators on one or more members to obtain a resultant action in which only the parameter measured by this sensor is influenced while the secondary repercussions on the outer parameters are eliminated. Another characteristic, the invention permits rapid intervention taking into account the information on the substance flow rate at the headbox, eliminating the usual disturbing influences due to the hydraulic values of the process.

Abstract: A particular papermachine and type of pulp stock for forming a particular basis weight web are analyzed for deriving a correlation between pulp stock drainage rate and the lowest obtainable critical moisture content of said paper web. From knowledge of the lowest critical moisture content and main steam pressure, differential pressure values between the several dryer pressure sections of the papermachine are determined for drying said web along the most energy-efficient drying rate trajectory. Also disclosed is a dryer steam pressure differential control program for maintenance of a pre-determined magnitude of condensate inventory within the drying cylinders under normal running conditions and under conditions of interrupted web continuity.

Abstract: The characteristic profile of a paper web is adjusted on the fourdrinier by means of a number of fluid spray stations positioned across the papermachine. Each spray station is provided with two or more fan spray nozzles of different flow capacity oriented to impact the pond with fluid along a common line. Flow to each nozzle is binary controlled with respective binary command, full flow valves. By discrete manipulation of valve selection, total flow rate to the web may be adjusted without flow throttling and consequent impact velocity variations.

Abstract: A method of on-line control of opacity of moving sheet material being produced by a paper making machine includes an opacity control loop where an opacity additive is controlled and a basis weight control loop where the stock input to a headbox is controlled. These two control loops are decoupled by means of an opacity to stock feed forward and a basis weight to titanium dioxide feed forward. In addition, the effect of moisture change is decoupled from opacity.

Abstract: An improved process and apparatus are disclosed wherein the resin treatment of a web on a material treater is conducted at maximum throughput in response to especially impinging air velocity control in the dryer.

Abstract: At least one channel in a multi-channel paper machine distributor is maintained in flow velocity slave relation to another of the channels by monitoring the velocity with a pressure transducer of stock flow through the latter channel and by such monitoring controlling the stock velocity in the slave channel.

Abstract: A method for the control of basis weight of a sheet material made from liquid stock controls the consistency of liquid stock flowing to a flow box by a consistency feedback loop, and varies the level of liquid stock in the flow box to effect a change in the flow of dry fiber to the sheet former. Level is maintained in a midrange and any level called for outside of midrange is handled by adjusting consistency.

Abstract: Undesirable high concentrations of fiber and moisture in the cross-direction profile of a paper stock slurry laid upon a papermachine fourdrinier screen may be selectively dispersed to level the cross-direction profile by impacting the screen carried pond of slurry at 1.5 to 4 feet down from the headbox slice opening with a fluid spray issued under a pressure drive of from 20 to 100 psi. If a cross-direction high concentration of fiber is to be corrected, the appropriate spray fluid to be used is water. If a cross-direction high concentration of water unaccompanied by a cross-directionally aligned high concentration of fiber is to be corrected, the appropriate spray fluid to be used is air.