岳阳造纸厂^#1纸机的技术改造（上）

The Technical Rebuiding of PM1 in Yueyang Paper Mill

岳阳造纸厂3950纸机,为适应将凸版印刷改为胶版印刷的要求,进行了有针对性的较全面的技术改造。主要引进了世界70年代末、80年代初先进适用的工艺和装备。1987年8月投产后的一年多证实改造是成功的。本文从技术上总结了这次改造和投产运行中的主要经验。

The 3.95m wide newsprint machine made by Finland in late 50th in Yueyang Paper Mill was rebuilt to produce printing paper for letter press and/or offset printings with bleached sulfate reed pulps as a main furnish.Major rebuilds adopted advanced technique & technology from Beloit U. S. A. include a new stock approach system, the installations of a thinchannel converflo headbox,a new Bel-Form former on the top of the fourdrinier, a Beioit Tri-vent press, a fixed Queen 4-roll calender with 2 c. c. roll and a 4150 A - 24 shaftless rewinder, etc. The sectional electric drive including DC motors & thyristor control system was suppliedby AEG, west Germany and a AccuRay 1180 microsystem was introduced to control thebasis weight & moisture content as well as to monitor the caliper of paper profileduring machine operating.Since Aug. 1987, the rebuilt machine has been on stream and the operations of more than one year have proved the success of this rebuild. The paper quality has beenconformed to the requirement of offset printings. The machine speed has been raised from 420 m/min to 535 m/min and the 1st year sellable production reached 35.5 thousand tons as previously expected. The rebuilt machine has also demonstrated a betterTunnablity with a reduction of web break, approximately 40%, and paper loss on rewinderbeing 2.3%less than before. As a result, a comparatively better economical benefitshave been acquired.This paper summarizes Mill's main experience in both rebuilding and operation, such as the using of fabrics, the top wire former, the reduction of paper break time and the improvement of machine efficiency.