| 摘要 |
<p>A headbox for delivering a multilayer stock jet to a forming surface in a twin-wire former comprises a slice chamber with a slice opening, at least one separator vane arranged in the slice chamber and extending from headbox side wall to headbox side wall and in addition right up to or, more preferably, out through the slice opening, and means for anchoring the vane at its upstream end. To enable the headbox to discharge a multilayer stock jet with characteristics such that the paper web produced has improved layer purity and formation, the anchoring means are designed to produce a rigid clamping of the vane, which has a bending rigidity that is sufficient to permit the stock flow on both sides of the vane to take place at such different pressures in relation to one another and such different flow velocities in relation to one another that the headbox is capable of delivering a smooth and stable multilayer stock jet with a velocity difference of at least about 15m/min. between at least two adjacent layers in the stock jet.</p> |
