Abstract: A measurement apparatus for weight measuring composite sheet including a sheet material having a second material thereon as a coating and/or as embedded particles therein. The apparatus includes an x-ray sensor for providing an x-ray signal from x-ray irradiating the composite sheet and an infrared (IR) sensor for providing an IR signal from IR irradiating the composite sheet. A computing device is coupled to receive the x-ray signal and the IR signal that includes a processor having an associated memory for implementing an algorithm, where the algorithm uses the x-ray signal and the IR signal to compute a plurality of weights selected from a weight of the sheet material, a weight of the second material, and a total weight of the composite sheet.

Abstract: A machine direction (MD) position profile measurement of a moving sheet records the MD position of each of the cross direction (CD) measurements. A sheet monitoring system includes means for measuring the MD speed of the sheet of material; means for associating measured MD speed with time to generate time-associated MD speeds; means for recording the time-associated MD speeds; a first scanning sensor for measuring a first characteristic of the sheet material wherein the first scanning sensor is located at a first position along the MD and the first scanner sensor traverses back and forth along a CD; and means for associating first characteristic measurements with time to generate time-associated first characteristic measurements. Single and multiple scanning sensors can be employed. For multiple scanner systems where the scanners are synchronized, the technique enables recreation of the real zig-zag measurement path and same spot measurements.

Abstract: A measurement apparatus includes an x-ray sensor including an x-ray source having a high voltage power supply for emitting an x-ray spectrum and an x-ray detector for providing a measured x-ray signal value responsive to the x-rays received after transmission through a coated substrate including a sheet material having a coating material thereon. A second sensor is a beta gauge or infrared sensor for providing a second sensor signal that includes data for determining a total weight per unit area of the coated substrate or of the sheet material A computing device receives the measured x-ray signal value and the second sensor signal configured to implement an x-ray based calculation that utilizes absorption coefficients for the coating material and sheet material, the measured x-ray signal value, the x-ray spectrum, and the weight measure as a calculation constraint, for computing at least the weight per unit area of the coating material.

Abstract: A measurement apparatus includes a beta gauge for generating a first sensor response signal from a composite sheet including a sheet material having a coating thereon including a high-z material or the sheet material has particles including the high-z material embedded in the sheet material. A second sensor being an x-ray or an infrared (IR) sensor provides a second sensor response signal from the composite sheet. A computing device is coupled to receive the first and the second sensor response signal that includes a processor having an associated memory for implementing an algorithm that uses the first and the second sensor response signal to simultaneously compute two or more weight measures selected from (i) a weight per unit area of the high-z material, (ii) a weight per unit area of the sheet material, and (iii) a total weight per unit area of the composite sheet.

Abstract: A measurement apparatus includes an x-ray sensor including an x-ray source having a high voltage power supply for emitting an x-ray spectrum and an x-ray detector for providing a measured x-ray signal value responsive to the x-rays received after transmission through a coated substrate including a sheet material having a coating material thereon. A second sensor is a beta gauge or infrared sensor for providing a second sensor signal that includes data for determining a total weight per unit area of the coated substrate or of the sheet material A computing device receives the measured x-ray signal value and the second sensor signal configured to implement an x-ray based calculation that utilizes absorption coefficients for the coating material and sheet material, the measured x-ray signal value, the x-ray spectrum, and the weight measure as a calculation constraint, for computing at least the weight per unit area of the coating material.

Abstract: A measurement apparatus includes a beta gauge for generating a first sensor response signal from a composite sheet including a sheet material having a coating thereon including a high-z material or the sheet material has particles including the high-z material embedded in the sheet material. A second sensor being an x-ray or an infrared (IR) sensor provides a second sensor response signal from the composite sheet. A computing device is coupled to receive the first and the second sensor response signal that includes a processor having an associated memory for implementing an algorithm that uses the first and the second sensor response signal to simultaneously compute two or more weight measures selected from (i) a weight per unit area of the high-z material, (ii) a weight per unit area of the sheet material, and (iii) a total weight per unit area of the composite sheet.

Abstract: A guided wave radar (GWR)-based method of measuring steam pressure includes transmitting at least a first microwave pulse signal from a GWR sensor system having a pulsed radar gauge (PRG) implementing a steam measurement algorithm coupled to a transceiver that is coupled to a GWR probe in a steam boiler tank having a reference reflector (RR) providing an impedance discontinuity. The transmitting the first microwave pulse signal is with water and steam in the steam boiler tank. An echo emanating from the RR is received responsive to the first microwave pulse signal generates that respective time of flight (TOF) measurement data. A refractive index value for the steam is determined from the TOF measurement data and a reference TOF value representing a TOF measurement without the steam in the steam boiler tank. A physical property of the steam is determined from the refractive index value, such as the pressure.

Abstract: A measurement apparatus for weight measuring composite sheet including a sheet material having a second material thereon as a coating and/or as embedded particles therein. The apparatus includes an x-ray sensor for providing an x-ray signal from x-ray irradiating the composite sheet and an infrared (IR) sensor for providing an IR signal from IR irradiating the composite sheet. A computing device is coupled to receive the x-ray signal and the IR signal that includes a processor having an associated memory for implementing an algorithm, where the algorithm uses the x-ray signal and the IR signal to compute a plurality of weights selected from a weight of the sheet material, a weight of the second material, and a total weight of the composite sheet.

Abstract: A guided wave radar (GWR)-based method of measuring steam pressure includes transmitting at least a first microwave pulse signal from a GWR sensor system having a pulsed radar gauge (PRG) implementing a steam measurement algorithm coupled to a transceiver that is coupled to a GWR probe in a steam boiler tank having a reference reflector (RR) providing an impedance discontinuity. The transmitting the first microwave pulse signal is with water and steam in the steam boiler tank. An echo emanating from the RR is received responsive to the first microwave pulse signal generates that respective time of flight (TOF) measurement data. A refractive index value for the steam is determined from the TOF measurement data and a reference TOF value representing a TOF measurement without the steam in the steam boiler tank. A physical property of the steam is determined from the refractive index value, such as the pressure.

Abstract: A scanning measurement system includes independently driven, self-aligning, dual-sided heads. The system is configured to perform a method that includes receiving information associated with a discrepancy in a desired cross direction alignment of a first sensor head and a second sensor head that are disposed on opposite sides of a web of material and that are configured to move in a cross direction relative to the web. The method also includes adjusting a velocity of at least one of the sensor heads based on the received information to improve the cross direction alignment of the first sensor head and the second sensor head.

Abstract: Nuclear-based basis weight sensors are passline-sensitive. Error in measurement is induced when the sheet moves up and down in the gap between the radiation source and detector. A passline-insensitive basis weight sensor includes a triangulation sensor to measure the position of the sheet within the gap. The sensor and gap is characterized in the laboratory for its passline behavior over a range of basis weights. The curves are either parameterized or a lookup table is created for each weight and passline position and the data added to the sensor's processor. The basis weight measured can be automatically corrected to account for deviations from the passline or nominal path through the sensor.

Abstract: A scanning measurement system includes independently driven, self-aligning, dual-sided heads. The system is configured to perform a method that includes receiving information associated with a discrepancy in a desired cross direction alignment of a first sensor head and a second sensor head that are disposed on opposite sides of a web of material and that are configured to move in a cross direction relative to the web. The method also includes adjusting a velocity of at least one of the sensor heads based on the received information to improve the cross direction alignment of the first sensor head and the second sensor head.

Abstract: A method includes wirelessly transmitting one or more messages to a sensor assembly in order to synchronize a clock of the sensor assembly. The method also includes wirelessly receiving multiple sensor measurements of a characteristic of a web of material from the sensor assembly. The method further includes receiving timestamps and position data associated with the sensor measurements. In addition, the method includes correlating the sensor measurements, timestamps, and position data. The sensor measurements from the sensor assembly could be timestamped, and the position data could include timestamped position data. The timestamped position data could be received from a source other than the sensor assembly. The method can further include generating a cross direction profile of the web of material using the sensor measurements, timestamps, and positions.

Abstract: Nuclear-based basis weight sensors are passline-sensitive. Error in measurement is induced when the sheet moves up and down in the gap between the radiation source and detector. A passline-insensitive basis weight sensor includes a triangulation sensor to measure the position of the sheet within the gap. The sensor and gap is characterized in the laboratory for its passline behavior over a range of basis weights. The curves are either parameterized or a lookup table is created for each weight and passline position and the data added to the sensor's processor. The basis weight measured can be automatically corrected to account for deviations from the passline or nominal path through the sensor.

Abstract: A method includes wirelessly transmitting one or more messages to a sensor assembly in order to synchronize a clock of the sensor assembly. The method also includes wirelessly receiving multiple sensor measurements of a characteristic of a web of material from the sensor assembly. The method further includes receiving timestamps and position data associated with the sensor measurements. In addition, the method includes correlating the sensor measurements, timestamps, and position data. The sensor measurements from the sensor assembly could be timestamped, and the position data could include timestamped position data. The timestamped position data could be received from a source other than the sensor assembly. The method can further include generating a cross direction profile of the web of material using the sensor measurements, timestamps, and positions.

Abstract: Paper and continuous web scanners operate at varying and high temperature conditions. Regulating the temperature within the measurement gap between dual scanner heads during measurement and calibration modes of operation by employing air wipe and sheet guide temperature control assures consistent and accuracy sensor measurements of sheet characteristics. Air wipes blow pre-heated air into the measurement and the sheet guides are heated. The air temperature fluctuations that otherwise caused significant adverse effects on the sensors that measure, for example, the basis weight, ash content, and thickness of the moving sheet, are eliminated.

Abstract: An improved differential coat weight technique employs a novel algorithm for measuring the weight of a coating material that has been deposited onto a sheet of substrate. The invention employs dual x-ray or nuclear gauges such that, even though the downstream sensor is never exposed to uncoated sheet substrate, imparting the downstream sensor with the ability to predict results that it would have yielded when measuring the uncoated sheet substrate, leads to the development of a coat weight calibration protocol from which the basis weight of the coating can be ascertained directly from measurements from the upstream and downstream sensors. No subtraction of results is required. Moreover, the two sensors do not need to be re-calibrated whenever the relative proportions of the coating and base substrate change. The technique is particularly suited for applications where the coating material and substrate are made of substances that have very different atomic numbers.

Abstract: Paper and continuous web scanners operate at varying and high temperature conditions. Regulating the temperature within the measurement gap between dual scanner heads during measurement and calibration modes of operation by employing air wipe and sheet guide temperature control assures consistent and accuracy sensor measurements of sheet characteristics. Air wipes blow pre-heated air into the measurement and the sheet guides are heated. The air temperature fluctuations that otherwise caused significant adverse effects on the sensors that measure, for example, the basis weight, ash content, and thickness of the moving sheet, are eliminated.

Abstract: Ash composition measurements of calcium carbonate and gypsum in paper is accomplished with a dual X-ray sensor system with one X-ray source that is powered at about 5.9 KV and a second X-ray source that is powered at about 4.2 KV. Corresponding detectors measure radiation from the respective X-ray sources that is emitted from the paper. Data derived from the measurements yields the gypsum and crystal water content in the paper. The dual X-ray sensor system can be employed in conjunction with infrared total moisture measurements of paper products being manufactured on a papermaking making machine, which contain gypsum and calcium carbonate, in order to correct for the gypsum crystal water effect.

Abstract: An improved differential coat weight technique employs a novel algorithm for measuring the weight of a coating material that has been deposited onto a sheet of substrate. The invention employs dual x-ray or nuclear gauges such that, even though the downstream sensor is never exposed to uncoated sheet substrate, imparting the downstream sensor with the ability to predict results that it would have yielded when measuring the uncoated sheet substrate, leads to the development of a coat weight calibration protocol from which the basis weight of the coating can be ascertained directly from measurements from the upstream and downstream sensors. No subtraction of results is required. Moreover, the two sensors do not need to be re-calibrated whenever the relative proportions of the coating and base substrate change. The technique is particularly suited for applications where the coating material and substrate are made of substances that have very different atomic numbers.