| 摘要 |
A headbox for a papermaking machine having vertical rectangular guide vanes defining channels therebetween for the flow of dilute paper stock toward a slice opening over a Fourdrinier wire. The guide vanes are provided with keys projecting horizontally from the vanes and into keyways defined by shelves projecting toward the guide vanes from vertical front and rear wall assemblies of the headbox. A pair of spacers is arranged between each pair of adjacent vanes, with one spacer providing a channel floor and the other spacer providing a channel ceiling. Each spacer has a key on both ends thereof. The keys of both the vanes and the spacers, in side abutting and alternating arrangement, project into a keyway. The keyways support the vanes and spacers between front and rear wall assemblies with cross-machine deflection of the flow passages, due pressure of pulp stock therein, being both minimized and made independent of headbox width. Pressurized chambers below and above the channels load the vanes and spacers against deflection in vertical planes defined by the vanes and spacers.
|
