Abstract: A process for operating a press section for producing a fibrous material web, with a nip that is elongated in the direction of web travel that includes an inlet zone, a main pressing zone, and an outlet zone, and where a pressure gradient of pressure p exerted in the main pressing zone of the nip is selected as a function of whether the fibrous material web entering in the nip has an average or high dry matter content, on the one hand, or a low dry matter content, on the other hand.

Abstract: System and method for producing paper are provided. The system controls formation of wet stock comprising fibers on a moving water permeable wire of a de-watering machine that has means for supplying the amount of pulp from at least one source, means for adding an amount of non-fibrous additives to the wet stock, a refiner that is subject to a variable load and a headbox having at least one slice, wherein each slice has an aperture through which wet stock is discharged onto the wire.

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 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: A system and method of producing a paper product from a wetstock solution using a sensor for sensing resistive impedance changes of the wetstock on the support web of the system. The resistive impedance changes are used to measure physical characteristics such as water weight of the wetstock on the support web of a sheetmaking system. The system includes a fixed impedance element coupled in series with a sensor portion between an input signal and ground. The sensor portion is an electrode configuration which includes at least two electrodes with a portion of the wetstock residing between and in close proximity to the electrodes. The sensor exhibits a variable impedance resulting from changes in the physical characteristics of the wetstock.

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: The apparatus and method of the present invention generates and controls an air-atomized spray, for application of moisture to a moving sheet, such as paper or converted paper products (e.g. corrugated board). The air-atomized water spray is generated by mixing a metered quantity of water with a constant air volume. In a representative embodiment the water flow is metered by adjusting the axial position of a shut-off needle relative to a circular control orifice. The needle is positioned by pushing and pulling upon it with a thermally-expanded metallic element. The thermally expanded element is heated directly or indirectly, at a controlled rate, to produce the desired needle movement and resultant water flow. A series of such controllable nozzles can be mounted across the width of a sheet to permit localized, metered moisture application to each cross-machine control zone.

Abstract: A basis weight scanner using a beta-ray source and an electron detector on opposite sides of a web of wood pulp sheeting is used to calculate the weight of wood pulp advanced past a measuring location (e.g. into a cellulosic fibre production plant).

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: A web rewet moisture actuator in which a plurality of air atomizing nozzles at spaced locations along a boom extending across the web are supplied with air under pressure by an air manifold on the boom and are supplied with water from a water manifold on the boom through respective proportional valve assemblies which permit flows therethrough in proportion to the magnitudes of control signals applied to the assemblies. A unit located downstream of the boom obtains a moisture profile across the web from which location and control signals are derived and fed to the valve assemblies to control the liquid flow through the valve assemblies in proportion to the magnitudes of the control signals.

Abstract: A sheet manufacturing system having a steam profiling bar, a moisture profiling bar, a moisture sensor and a computer is disclosed. The computer is programmed to cause the correct amount of steam or water to be applied on a slice-by-slice basis based upon the moisture content profile data generated by the moisture sensor as compared against a preprogrammed, desired moisture content profile. The computer is programmed in such a way as to cause either steam or water, but not both, to be applied as needed to any given portion of each individual slice to achieve the desired moisture content profile. Thus, the combined application of both steam and water to the same portion of the sheet, and the nullifying effects thereof, are avoided, resulting in the use of less steam and less water while still providing full control over the moisture content profile with only one moisture sensor.

Abstract: A sheet manufacturing system having a steam profiling bar, a moisture profiling bar, a moisture sensor and a computer is disclosed. The computer is programmed to cause the correct amount of steam or water to be applied on a slice-by-slice basis based upon the mositure content profile data generated by the moisture sensor as compared against a preprogrammed, desired moisture content profile. The computer is programmed in such a way as to cause either steam or water, but not both, to be applied as needed to any given portion of each individual slice to achieve the desired moisture content profile. Thus, the combined application of both steam and water to the same portion of the sheet, and the nullifying effects thereof, are avoided, resulting in the use of less steam and less water while still providing full control over the moisture content profile with only one moisture sensor.

Abstract: The invention relates to a process for wetting a paper web in a calendering step by using water-containing microcapsules in the surface structure layer of the paper web, said microcapsules being ruptured in the calendering step whereby water is released. The invention also relates to microcapsules comprising a water-impermeable shell and an interior substantially comprising water, and having a diameter of 0.1 to 100 .mu.m and a shell thickness of 0.01 to 5 .mu.m.

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: A measuring gauge for error compensation of a measured characteristic of a moving sheet measures X, Y lateral displacement of the upper and lower transducer heads of a moving scanner in a cross direction across the paper. This is accomplished by the use of two pairs of eddy current sensors centered on a target on the opposed transducer head. Such eddy current transducers sense the pairs of edges of an aperture in the opposed transducer. Alternatively, slope portions of the lower transducer head are sensed. Other correction inputs are provided by measuring the distance from each transducer head to the moving sheet to provide a "Z" correction. All of the foregoing are then utilized along with caliper measurements, if necessary, to provide a corrected characteristic.

Abstract: A system and process for controlling the displacement of a thickness regulating member which regulates the basis weight of a sheet being formed from fluid material. The displacement of the thickness regulating member is determined by measuring the forces which slice rods exert on the thickness regulating member.

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 modified infra-red scanning gauge used in measuring the moisture content of a paper-web during manufacture or when subject to a coating practice, has a measurement channel and a reference channel. The measurement channel is based on the infra-red absorption spectrum of water which has an absorption band centered on 1.94 microns. The reference channel is conventionally at a wavelength of 1.83 microns where water has previously been considered to be transparent to infra-red or at a wavelength of 1.68 microns. The gauge is intended for measurement of high water content, where at 1.94 microns absorption effectively becomes total thereby preventing measurement being made, and uses a narrow-band filter of 0.03 micron wavelength offset from the peak of the 1.94 micron absorption band in the range 1.76 to 1.87 microns, previously considered stable as regards water content but now disclosed as showing a water-dependent variation at high water contents. In a specific example a 1.

Abstract: Method and apparatus are provided for effectively controlling cross-machine moisture profile in a paper web undergoing processing, such as water-removal via a press nip. A compartmentalized system is provided in close proximity across a section of a traveling web undergoing dewatering whereby select size cross-machine compartments, for example, about 6" in width, are selectively provided with steam and/or air so as to control wet and/or dry streaks along the traveling web so that web areas opposite each compartment can be selectively heated for accentuated moistre removal or cooled for retarded water removal. In preferred embodiments, control of the profiling system occurs with the air of moisture sensors and a computer.

Abstract: A first flexible vessel of a first cross section communicates with the rod and a second flexible vessel of a second cross section, different from the first cross section communicates with the first vessel. A substantially incompressible fluid is contained in the first and second vessels. Movement of a heated rod against the first expansible vessel moves liquid to the second expansible vessel, the differing cross section ensuring that the longitudinal movement of the second vessel is different from that of the rod.

Abstract: A method for the moistening of an endless web moving in a processing device, wherein the moistening substance is an evaporated fluid condensated on the web and said web is treated with a corresponding steam substance prior to this moistening. The method includes steps for supplying the evaporated fluid in a bag-like member formed by the web, the bag-like member being supported by an external member. The supply of the substance is carried out by means of a steamer appliance arranged transverse to the web. The method includes steps for adjusting the specific property of the steam substance in accordance to specific values measured from the web.

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: Apparatus to supply steam to a paper sheet passing beneath it. The apparatus has a leading edge and a trailing edge relative to the sheet direction and comprises at least two headers, a first header being adjacent to the leading edge. There is a steam supply system means for the headers. A profiling chamber is formed between the headers and baffles which divides the profiling chamber into compartments. There is provision for a controlled supply of steam to each compartment. Outlets in the profiling chamber permit steam to be projected towards the sheet from the compartments. A further chamber is formed adjacent to the leading edge and steam can be supplied to the chamber. Outlets in the further chamber permit steam to be directed towards the sheet to form a steam curtain at the leading edge of the apparatus to prevent air being drawn under the apparatus by the sheet.

Abstract: Tearing, blistering, delamination and other defects in deep drawn plastic laminated paperboard containers are eliminated by adding controlled amounts of warmed moisture to the paperboard immediately prior to forming thereof. Water is heated to a desired temperature and is applied by in-line processing equipment to the unlaminated side of the paperboard which functions to both soften and paperboard and preheat the laminate. By heating both the male and female parts of a die press employed for forming the preheated, softened laminate into the container, preheating the laminate using warm water prior to forming and, continuously controlling the moisture added to the paperboard, the degree of stress imposed on the plastic layer of the laminate and the resulting defects in the formed container are significantly reduced.

Abstract: A steam shower for reducing paper web moisture content variability in the cross machine direction is described. The local dewatering effect of the shower on the moving supported web is controlled by varying its bottom steam discharge area incrementally across the width of the web. In one embodiment the hood is divided across the width of the machine into compartments, each having at least one cross machine direction wall whose bottom edge may be adjusted relative to the rear wall of the hood. A second embodiment has a pleated curtain whose bottom edge is controlled by lever arms with respect to the hood's rear wall. Local adjustments are made based on a comparison of moisture measurements at the finished product reel with the desired level.

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: 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.