Abstract: A method for controlling a slice flow of a slurry having two or more component slurries through a headbox for a paper making machine includes, inputting a wire speed of the paper making machine; determining a jet velocity setpoint based on the wire speed; determining a header pressure setpoint for two or more headers to generate the jet velocity determined by the jet velocity setpoint, each header providing one of the two or more component slurries to the headbox; and controlling the slice flow by: generating a first speed command to a first slurry pump to generate a header pressure determined by the header pressure setpoint in a first header; and generating a second speed command to a second slurry pump to generate the header pressure determined by the header pressure setpoint in a second header.

Abstract: A method for controlling a slice flow of a slurry having two or more component slurries through a headbox for a paper making machine includes, inputting a wire speed of the paper making machine; determining a jet velocity setpoint based on the wire speed; determining a header pressure setpoint for two or more headers to generate the jet velocity determined by the jet velocity setpoint, each header providing one of the two or more component slurries to the headbox; and controlling the slice flow by: generating a first speed command to a first slurry pump to generate a header pressure determined by the header pressure setpoint in a first header; and generating a second speed command to a second slurry pump to generate the header pressure determined by the header pressure setpoint in a second header.

Abstract: A forming section for a twin fabric papermaking machine, wherein after stock impingement, the two fabrics carry and sandwich the stock. A plurality of spaced apart drainage shoes, selectively provided to either or both of the fabrics, provides continuous support in the machine direction for the respective fabric in sliding contact, and each drainage shoe deflects the fabrics by a selected angle of wrap comprising an angular displacement between the leading edge and the trailing edge of the drainage shoe. At least one of the drainage shoes is secured to a drainage box and is provided with a plurality of drainage openings extending from the fabric contacting surface through to the machine side surface of the shoe. The arrangements of the invention provide improved drainage and formation of the paper web.

Abstract: A forming section for a twin fabric papermaking machine, wherein after stock impingement, the two fabrics carry and sandwich the stock. A plurality of spaced apart drainage shoes, selectively provided to either or both of the fabrics, provides continuous support in the machine direction for the respective fabric in sliding contact, and each drainage shoe deflects the fabrics by a selected angle of wrap comprising an angular displacement between the leading edge and the trailing edge of the drainage shoe. At least one of the drainage shoes is secured to a drainage box and is provided with a plurality of drainage openings extending from the fabric contacting surface through to the machine side surface of the shoe. The arrangements of the invention provide improved drainage and formation of the paper web.

Abstract: A headbox including a stock dilution profiling arrangement and associated stock delivery systems are provided, which together deliver to the forming section of a papermaking machine a uniform stock flow with more consistent basis weight and fiber orientation profiles than has previously been possible. These improvements in basis weight uniformity and fiber orientation profile provide benefits in paper sheet formation and related paper properties.

Abstract: A cleaning apparatus is disclosed for cleaning a forming wire of a paper machine. The apparatus includes a shower which is disposed adjacent to the forming wire for applying a shower of cleaning fluid to the wire. A blow box is disposed closely adjacent to the forming wire and downstream relative to the shower. The box is connected to a source of pressurized air for blowing a jet of air through the wire for removing the cleaning fluid therefrom. A plate is disposed between the box and the wire. The plate defines a plurality of slots which are disposed obliquely to a direction of movement of the wire in order to supply a multiplicity of pressure pulses to the wire for removing contaminants therefrom.

Abstract: A cleaning apparatus is disclosed for cleaning a forming wire extending around a wire turning roll of a paper machine. The apparatus includes a shower which is disposed upstream relative to the turning roll for spraying a cleaning liquid onto the forming wire. A housing is disposed between the shower and the turning roll, the housing being connected to a source of pressurized air. The housing defines an opening which has a first and a second end. The housing also defines an orifice which has an upstream and a downstream end for permitting a flow therethrough of the pressurized air such that the flow of air is directed against the wire for at least partially removing the cleaning liquid therefrom. The opening cooperates with the turning roll such that the opening conforms with the turning roll for substantially sealing the opening against loss of the pressurized air so that the flow of pressurized air is directed through the orifice.

Abstract: A coater apparatus is disclosed for applying a primary flow of coating material to a moving web of paper. The apparatus includes a frame and a first and a second guide roll rotatably supported by the frame. The first and second guide rolls rotate respectively around first and second rotational axes. The second axis of rotation is disposed spaced and parallel relative to the first axis. A backing blanket extends around and is guided by the guide rolls. The blanket defines an endless loop around the guide rolls such that the web of paper is supported by the blanket during movement of the web from the first guide roll to the second guide roll. The blanket is disposed between the web and the guide rolls. A short dwell coater is disposed adjacent to the web and between the guide rolls for applying the primary flow of coating material to the web.