Cylinder paper machines

Continuous paper machines have undergone extensive mechanical developments since the 1950s, although the principles employed have changed Utde. Cylinder machines stUl are operated and involve multiples of five to seven cylinders they are used to produce heavy multi-ply boards. Fourdriniers are common in the industry and can be used to produce virtually any grade of paper or paperboard. They vary from 1 to 10 meters in width and, including the press and dryer sections, may be more than 200 m long. 

Using a revolving cylinder or other equipment (save-alls), in the 1930s mills recovered for reuse fibers and clay from the paper machine... 

Continuous sheet/film h ilm/sheet Cylinder Conduction Paper machine, roller... 

Cylinder Dryers and Paper Machines The most common type of dryer in papermaking is the cylinder dryer (Fig. 12-84), which is a... 

Paper/board produced Fine paper machines generally have a greater need for retention than drainage, whereas board machines are the opposite. Newsprint/LWC/ SC machines require both retention and drainage. Tissue machines are notoriously difficult in terms of applying retention aids due to the low basis weights produced and effects on cylinder adhesion etc. 

The multicylinder dryer section of a paper machine consists of a number (up to 70) of large, hollow, cast iron or steel cylinders over which the web passes. These cylinders are nsed to alternately heat the two sides of the sheet. The major mode of heat transfer is the conduction through the steam-heated cylinder shells. 

Typically, the dryer cylinders are made of cast iron and have diameters of 0.91-1.83 m (mostly 1.52-1.83 m in modem machines). The length of the cylinders ranges up to 9.1 m for the largest paper machines. The shell thickness varies with diameter but is generally around 25.4 mm or more. The design and manufacture of these cylinders have important... 

Paper Machine Drying-Cylinder End-Cap Insulation, Energy Efficiency Demonstration Scheme, Project Profile 114, Energy Efficiency Office, U.K. Department of Energy (October 1986). 

Wet pulps are used in specialty paper applications such as speaker cones, filtration, and specialty papers. These pulps have been successfully processed on cylinder, rotoformer, and Fonrdrinier paper machines. As little as 15% of a highly fibrillated pulp can interlock other fibers or powders without the need for resin binders. 

Drying of the paper web from about 35-50% dry content to about 90% dry content is performed in the dryer section of the paper machine where cylinders are heated with low pressure steam. For removal of moisture, supply air at 95°C is blown into the paper... 

The paper machine dryer section is built with 30 % impingement drying and 70 % cylinder drying. It is assumed, that due to the impingement drying 6 kg/s of HR-steam becomes available for ORC. 

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