US 7,536,806 B2
Arrangement in a paper machine
Kari Juppi, Palokka (Finland); Antti Komulainen, Keuruu (Finland); Markku Lummila, Jyväskylä (Finland); Michael Odell, Jyväskylä (Finland); Martti Salminen, Jyväskylä (Finland); Riikka Antikainen, Muurame (Finland); and Petter Honkalampi, Kinkomaa (Finland)
Assigned to Metso Paper, Inc., Helsinki (Finland)
Appl. No. 10/597,175
PCT Filed Jan. 14, 2005, PCT No. PCT/IF2005/050006
§ 371(c)(1), (2), (4) Date Aug. 31, 2006,
PCT Pub. No. WO2005/068713, PCT Pub. Date Jul. 28, 2005.
Claims priority of application No. 20040049 (FI), filed on Jan. 15, 2004; and application No. 20045148 (FI), filed on Apr. 23, 2004.
Prior Publication US 2007/0084078 A1, Apr. 19, 2007
Int. Cl. D06F 58/00 (2006.01); F26B 3/00 (2006.01)
U.S. Cl. 34—114  [34/115; 34/464; 34/619; 34/620] 18 Claims
OG exemplary drawing
 
1. A method of improving runnability and allowing for shortened dryer section of a paper or board machine comprising the steps of:
after pressing a paper or board web in a press nip of a pressing section, drying a first side of the paper or board web by blowing air or other hot gas of a temperature of 250° C.-700° C. directly on to the first side of the paper or board web in a pre-impingement dryer in which impingement takes place directly against the paper or board web and not through a fabric;
within a maximum distance of 4 meters of the pre-impingement dryer, drying the second side of the paper or board web in a second impingement dryer with blowing air or other hot gas of a temperature of 250° C.-700° C. on two sides of a loop formed by a support fabric, wherein the loop is in the vertical direction longer than its machine-directional dimension and is arranged such that the support fabric remains on the side of the paper or board web opposite blowing air;
keeping the paper or board web attached to the support fabric using internal suction devices, which direct a suction effect to the paper web from inside the support fabric;
within a maximum distance of 4 meters of the second impingement dryer, drying the second side of the paper or board web in a first group of steam heated dryer cylinders;
contacting the web second side to a drying surface of a first dryer cylinder of the group of steam heated dryer cylinders having a temperature of approximately 80° C. and up to 130° C., wherein said drying surface is the drying surface of the first group of steam heated dryer cylinders to first contact the web; and
wherein the paper or board web is heated by the second impingement dryer to a temperature which deviates less than 15° C. from the drying surface of the first dryer cylinder of the first group of steam heated dryer cylinders.