Convergent flow headbox

摘要

A headbox having a tube bank composed of a multiplicity of tubes arranged in machine direction rows of superpositioned tubes. The tubes extend from an unitary outlet wall of the headbox and are supplied by a single header or manifold. The tubes extend to the inlet of a single nozzle which is formed with an upper planar wall which converges toward a lower planar wall. The converging walls of the nozzle define two radially extending planes which converge at an imaginary centerline which extends in the cross-machine direction. The individual rows of tubes each lie along a radial plane which extends through the centerline. The radial planes defined by each tube row will preferably be evenly spaced in angle between the nozzle walls. The injection ends of the tubes lie on a defined cylindrical surface extending between the nozzle walls and extending the width of the headbox in the cross machine direction.