Abstract:
Multiple groups of sensors are circumferentially spaced apart at each cross-directional position along a sensing roll of a nip press to measure and cancel or nearly cancel the effects of rotational variability which may be acting on the sensing roll. The strategically-placed sensors are designed to measure the pressure being placed against the web that is being advanced through the nip press. The average of the measurements of multiple sensors spaced circumferential apart provides a good cancellation of any rotational variability that might be found at a cross-directional position on the sensing roll. In this manner, a more true measurement of the nip pressure profile can be obtained and better adjustments made to reduce nip pressure profile variability. In addition, the nip variability profile may be used as a predictor of cover or bearing failures, resonant frequencies and other roll anomalies.
Abstract:
Multiple groups of sensors are circumferentially spaced apart at each cross-directional position along a sensing roll of a nip press to measure and cancel or nearly cancel the effects of rotational variability which may be acting on the sensing roll. The strategically-placed sensors are designed to measure the pressure being placed against the web that is being advanced through the nip press. The average of the measurements of multiple sensors spaced circumferential apart provides a good cancellation of any rotational variability that might be found at a cross-directional position on the sensing roll. In this manner, a more true measurement of the nip pressure profile can be obtained and better adjustments made to reduce nip pressure profile variability. In addition, the nip variability profile may be used as a predictor of cover or bearing failures, resonant frequencies and other roll anomalies.
Abstract:
A sensor signal is generated from a plurality of sensors located on a sensing roll, wherein each sensor enters a nip between the sensing roll and a rotating component during each rotation of the sensing roll. A rotating applicator rod forms forming a second nip with the sensing roll such that each sensor enters the second nip during each rotation of the sensing roll and each sensor generates a sensor signal upon entering the second nip. A periodically occurring starting reference is generated associated with each rotation of the applicator rod and the signal generated by each sensor is received so that a particular one of the sensors which generated the signal is determined and one of a plurality of tracking segments is identified. The signal is stored to associate the sensor signal with the identified one tracking segment.
Abstract:
Collecting data includes generating a sensor signal from each of a plurality of sensors located on a sensing roll, wherein each signal is generated when each sensor enters a region of a nip between the sensing roll and mating roll during each rotation of the sensing roll; wherein a web of material travels through the nip and a continuous band contacts a region of the web of material upstream from or at the nip. A periodically occurring starting reference is generated associated with each rotation of the continuous band and the signal generated by each sensor is received so that the one of the plurality of sensors which generated this signal is determined and one of a plurality of tracking segments associated with the continuous band is identified. The signal is stored to associate the respective sensor signal with the identified one tracking segment.
Abstract:
A roll for a machine for processing a material web, in particular a paper, cardboard, or tissue machine, has a cylindrical roll core and a roll cover which is arranged on the radially outer lateral face of the roll core. The roll cover has a functional layer and a connecting structure which lies radially between the roll core and the functional layer. The radially outer lateral face of the functional layer provides a contact surface which can be brought into contact with the material web or a covering. A plurality of pressure and/or temperature-sensitive sensors are embedded in the roll cover. The sensors are arranged in the connecting structure or at the interface between the connecting structure and the functional layer.
Abstract:
A machine for producing and/or processing a fiber web, in particular a tissue web, includes a press roll and a mating roll which forms a nip with the press roll and the circumferential surface of which has a contour running in the cross-machine direction which, during operation of the machine, changes as compared with when the machine is at a standstill. The press roll has a roll core and a roll cover surrounding the roll core. Multiple pressure and/or temperature sensors are disposed in the roll cover and/or between the roll core and the roll cover. The pressure and/or temperature sensors are spaced apart differently far from one another in the cross-machine direction of the press roll, at least in some areas.
Abstract:
A belt press for a paper machine, the belt press including a roll having an exterior surface and a permeable belt. The permeable belt has a first side and is guided over a portion of the exterior surface of the roll. The permeable belt has a tension of at least approximately 30 KN/m, the first side has an open area of at least approximately 25% and a contact area of at least approximately 10%.
Abstract:
Methods for dewatering a fiber suspension in a twin-wire press, having a lower wire and an upper wire, and a first and a second dewatering table, which supports the wires such that a dewatering space is defined by the wires, are disclosed. The wires transport the fiber suspension under compression of the wires by the dewatering tables, such that the fiber suspension is dewatered and forms a fiber web between the wires. A separate pressing force is applied against one of the wires, such that this wire presses the formed fiber web via the second wire against one of the dewatering tables and further dewaters the fiber web. The separate pressing force is adjusted such that a desired dryness of the fiber web leaving the dewatering tables is achieved. A twin-wire press is also disclosed.
Abstract:
System and method for influencing and/or monitoring a press pressure profile along at least one of a web running direction and a transverse direction in an extended press nip used for treating a material web. The system includes a measuring device for measuring the press pressure profile, a profiling arrangement which participates in producing the press pressure profile, and a data storage device for storing data related to the profiling arrangement. The method includes storing, in a data storage device, data relating to a profiling arrangement which participates in producing the press pressure profile, retrieving the data and acting on the profiling arrangement based on the data. This Abstract is not intended to define the invention disclosed in the specification, nor intended to limit the scope of the invention in any way.
Abstract:
An extended nip press having a concave shoe which is supported on a hydraulic actuator which urges the shoe against a backing roll. A pair of opposed profile control hydraulic actuators apply a pure couple about the load support line formed by a bearing pin which transmits the support load from the hydraulic actuator to the shoe. A leading hydraulic actuator is positioned in front of the load support line and pulls down on the shoe. A trailing hydraulic actuator is positioned behind the load support line and pushes up on the shoe. The leading hydraulic actuator and trailing hydraulic actuator are equally spaced from the load support line and have equal hydraulic actuator area and are connected to the same hydraulic reservoir. Thus the hydraulic actuators exactly balance each other out except for the couple or torque which they apply about the load support line.