ADJUSTABLE ACTIVITY DRAINAGE BOX

摘要

A process, and an apparatus, for improving sheet properties in the initial impingement zone of a paper making machine including a forming section, a forming fabric moving in the machine direction and a head box having a head box slice which delivers a stock jet onto the moving forming fabric. The sca le and intensity of agitation within the stock is adjusted by moving some of th e support elements beneath the forming fabric adjacent the head box slice so that they either contact, or do not contact, the machine side surface of the forming fabric. This technique is of use in a papermaking machine forming section having a single open surface forming fabric, in the initial open surface section of a so-called hybrid gap former having two superposed formi ng fabrics, and in the forming section of a two fabric papermaking machine.