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 of optimizing the performance of a multi-unit power plant which produces both electrical and steam energy by determining the incremental efficiency of power boilers with various fuel inputs and thereafter determining the index of performance by taking into account cost factors and reallocating in the most optimum manner.

Abstract: A process for controlling the dry density of ceiling tile where a delayed measurement of thickness or caliper is compared with an off-line oven dry basis weight measurement of a previously taken sample to provide dry density which is then compared to a dry density target to yield an error signal which updates an on-line wet density indication to provide control of stock flow.

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: A method and apparatus for controlling the yield of fabric material from a tenter frame having spaced apart belts driven by drive means and an overfeed roll at its entry end. In a start-up or style change mode of operation a predicted dry yield is computed from data signals received before the fabric enters the tenter frame, then compared with a target value to produce a control signal to the overspeed roll. In the steady state mode of operation, actual yield is computed from data taken at the output end of the tenter frame; then is compared with a target yield value and thereafter modified by a correction factor proportional to variations in predicted dry yield computed from inputs taken at the entry to the tenter frame; the modified control signal again being applied to the overspeed roll.

Abstract: A titration apparatus and method therefor for determining the available alkali in a Kamyr or batch digester includes a sample vessel and a reference vessel suspended within the system itself in either the digester or associated pipelines. Carbon dioxide is used as a titrant and the end point is determined by a computer monitoring conductivity.

Abstract: An improved method and apparatus for measuring the moisture contained by a moving sheet of web material includes a water simulating filter in a typical dual wavelength moisture gauge which provides transmission ratios. The relationship between the change of ratios of various samples of the material with different moisture content with the change of the filter ratios when various layers of moist dirt are placed in the gauge transmission path is used to provide a corrected transmission ratio from which water weight can easily be determined. The method is also applicable to polymer coatings or similar substances.

Abstract: A method and apparatus for controlling the machine direction variations of a property or properties of a sheet material being processed. A scanning gauge moved back and forth across the sheet material as it is moved in the machine direction, takes measurements of the property being controlled at fixed intervals across the sheet and a true profile is computed from the measurements made. At the end of each scan of the gauge the average of all the true profile points is computed. A control variable affecting the sheet property is manipulated so as to maintain the machine direction property of the sheet at some target value as a function of the array of values comprising the true profile, the gauge readings of the sheet property and the true profile average.

Abstract: A method for controlling the weight per unit area of a tire fabric and changing from one code to another uses the difference between the nominal calender roller gaps for the old and new codes to preset the gaps for the new code before feedback control is resumed.

Abstract: An optical reflectance gauge which serves as a chlorination sensor for paper pulp in which a spectrum of the bulk of the material is obtained by use of displaced windows in the pulp pipe. One window has a radiation source associated with it and the other a radiation detector. The distance between such windows is determined to provide for insensitivity to small changes in consistency for measurement of chlorination. A mechanical arrangement is also provided for easier coupling of the gauge to a pulp pipe.

Abstract: Measuring apparatus is used as a control element to maintain the correct ratio of chlorine to pulp in a bleach plant. Two diffusing windows are used; one to randomly radiate electromagnetic energy into the pulp and the other to receive radiation from the bulk of the pulp and reradiate it. Two bands of radiation are examined; one in the visible and the other in the infrared. Rather than using a conventional beam splitter, two detection systems, differing only in their spectral pass band, are used. Their optical axes converge in the center of the receiving window so that identical images of the receiving window can be projected on each of the detectors. The detector system allows the use of interference type filters which require sensibly parallel radiation. In addition to sensing the brightness of pulp, which is affected by the amount of chlorine, the above apparatus is useful for concurrently measuring opacity, moisture content, and basis weight of a moving sheet.

Abstract: An automatic temperature control system for a textile tenter frame having an oven section for heating the fabric in order to "set" its fibers in an essentially non-shrinkable state. The system operates to maximize the speed of the tenter frame while maintaining optimum heat set conditions. Fabric temperature from within the oven and initial moisture content data are furnished to a computer and processed with time-at-temperature target inputs to provide tenter frame speed control output signals.

Abstract: Method and apparatus for controlling pulp refiners where a feed forward algorithm compensates for the time delay in the effective action of the base refiners which are coupled to a high frequency compensating tickler refiner by a machine chest which has a significant time lag. In addition, efficiency of the control system is enhanced by providing a simple control method for a complex series parallel matrix of base refiners where the change of specific energy is easily accomplished by a distribution algorithm.