Headbox and manifold system for producing a multi-ply paper web

摘要

The present invention involves a headbox and manifold system for producing a multi-ply paper which includes a plurality of mixing systems for generation of stock suspension flows of differing concentrations and a distribution manifold for providing a different stock suspension for each of the plies. For at least one of the plies, two conduits or manifolds are used to carry stock suspensions of differing concentrations thereby permitting the adjustment of the concentration of the stock suspension used to form that ply. Each manifold is fixed to the support structure of the paper making machine and runs transverse to the machine direction. Each of the manifolds is in fluid communication with the movable headbox by means of flexible lines of equal length. After discharge from the flexible lines the stock suspensions are routed through turbulence generators before being discharged from the headbox through a slice nozzle to form a multi-ply paper web. The slice nozzle has a width at least as large as the paper web which is formed.