Pulp and linerboard former with improved dewatering

Details Pulp and linerboard former with improved dewatering Pulp and linerboard former with improved dewatering

D - Textiles, Paper

21

F

D21F 9/00 (2006.01) D21F 1/80 (2006.01)

Patent

CA 2253570

An improved forming section of the twin wire type for a papermaking machine is described which increases the fibre content of the formed web of paper while reducing the use of energy intensive vacuum dewatering aids relative to prior apparatus. Stock is injected from the headbox of the machine onto a forming wire which is brought into gradual engagement with a second forming wire. The two wires are directed by a forming shoe along a path of increasing curvature, above which water is drained by adjustable auto slices. The two wires with the web therebetween then follow an oscillating S-path between seven S-rolls and are directed upwardly through three individually loaded press rolls with increasing pressure to about four hundred and fifty pounds per linear inch at the last wet press, the press rolls being individually pneumatically pivotable to increase nip pressure and collectively pivotable to open all the nips. Using a high pressure dry nip, the fibre content of the web can be increased to thirty-five percent fibre. Through improved water removal capabilities of the forming and pressing sections the head of the drying section in the papermaking machine, significant cost advantages are realized.

Dans une machine à double toile (20), une caisse de tête (30) injecte de la pâte à papier sur une toile de formation (22) avec laquelle une deuxième toile de formation (24) est mise en contact graduellement. Un sabot (40) dirige les deux toiles le long d'un trajet présentant une courbure croissante, au-dessus duquel l'eau est drainée au moyen de règles automatiques (44, 46) réglables. Les deux toiles (22, 24), ainsi que la bande (34) située entre elles, suivent ensuite un trajet oscillant en forme de S entre sept rouleaux en S (52) et sont dirigées vers le haut à travers trois rouleaux de presse (58) chargés individuellement et dont la pression augmente jusqu'à atteindre environ quatre cent cinquante livres par pouce linéaire au niveau de la dernière presse humide. Des cuvettes de drainage (83) recueillent l'eau depuis la surface supérieure de la double toile ainsi que l'eau rejetée depuis les rouleaux de presse supérieurs. Les rouleaux de presse peuvent pivoter pneumatiquement et individuellement, de manière à augmenter la pression au niveau de la ligne de contact des rouleaux et peuvent pivoter collectivement afin d'ouvrir toutes les lignes de contact. A proximité, une ligne de contact (80) à sec et à pression élevée peut augmenter la teneur en fibres de la bande (34) de 35 %.

Affiliated with

Also associated with

Rating

Pulp and linerboard former with improved dewatering does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Pulp and linerboard former with improved dewatering, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pulp and linerboard former with improved dewatering will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1663144