DE1810232A1 - Drying cylinder for pulp and paper - Google Patents

Abstract

Paper web drying cylinder Esp. for preventing overdrying of paper web edges. It is provided internally with a pair of partition walls which are disposed adjacent the ends of the cylinder to subdivide the cylinder into three chambers, the end ones of which are supplied with low pressure steam, condensate, air or water and the central chamber with high pressure steam.

Description

to-ΐπΐΓ. Wilhelm Belche J.

Frankfurt / Main-1
Park street 13

• 5746

INTERCATIONAL PAPER COMPANY, New York, N.Y., U.S.A.

Method and device for drying a "web-shaped
Materials

The invention relates to dryer rolls that are used in manufacture used by pulp and paper. It relates in particular to an improvement in the process and equipment for drying pulp, paper and other web materials during their manufacture.

Paper and other web-shaped materials are sorted according to their
Training on, for example, a Fourdrinier paper machine, dried by passing it over a series of drying cylinders that are heated inside and with high
Rotate speeds around their longitudinal axes. In this context, reference is made to the following publications, for example:

Modem pulp and paper making ; from Wit ham, G-. S. Reinhold
Publishing Corporation; New York, 1942; Pages 437 to 453 and

Pulp and Paper Manufacture (Vol. 3) by Stephenson, JN. (ed.); McGraw-Hill Book Company, Inc .; New York, 1953; Pages 301 to 369.

As a result of various venting and heat transfer problems encountered with the use of drying cylinders or rolls
occur, the sheet-like material that you dry

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would like, often along one or both of its margins dried too much while drying the middle part of the web properly. This excessive drying or Overdrying in turn leads to difficulties in calendering and winding the web-shaped material and can be detrimental influence on the ultimate use properties of the material.

In an article entitled "Improvement of Reel Moisture Profile by Dryer Insulation," which was published in the Pulp and Paper Magazine of Ganada in March 1959, JE Campbell and GD Hughson discuss attempts with a dryer cylinder liner that the arrangement encompassed by insulating means (brick) in circular rings inside a drying roller close to or on its end faces. It was assumed that the higher evaporation rate on the sides of the web to be dried in the main axis is due to the fact that a greater heat flow takes place from the dry steam to these points, as a result of the fact that the dryer head, i.e. the end, does not pass through a film of condensate is protected, or as a result of the fact that the interior of the drying cylinder jacket is cleaned by the steam and thereby an abnormally high overall heat transfer coefficient is generated, that the application of a barrier (the bricks) with poor thermal conductivity between the steam and the inner surface of the dryer, the reduction of this Could support evaporation rate. The item showed surprisingly consistent and very significant changes in the moisture profile as a result of the introduction of insulation.

Undoubtedly it is true that the reason for the deficient Industry interest in Campbell's article and Hughson suggests that the use of an insulating material (e.g., bricks) is manifestly impractical turned out to be loose and thereby the roller con-

00982 3/096

Densatsiphons and systems can endanger. Indeed were the bricks also loosely after a certain period of use.

The invention now shows a way to avoid excessive or excessive drying at the ends of the dryer rollers and at the same time the inadequate adjustability or adaptability to avoid lining the inside of the dryer rolls at their ends with bricks or the like. With calibrated., brought.

The invention will now be described in detail with reference to the accompanying drawings, all of which are taken from the description and the details or features emerging from the figures can contribute to the solution of the problem within the meaning of the invention and were included in the application with the intention of being patented. Show it:

Fig. 1 is an end view of the Trookner roll according to the invention; FIG. 2 is a longitudinal section along the line 2-2 of FIG. 1;

3 is a partial sectional view taken along line 3-3 of FIG. and

Fig. 4 is a schematic partial view of the adjustment device.

With reference to FIGS. 1 to 4, the method will also be explained. The invention has in the interior of a rotatable drying cylinder or a drying roller 12 along its longitudinal axis near at least one roller face 14 an adjustable partition wall arrangement 10 to form a closed zone 16 through the roller face 14, the partition wall 'arrangement 10 and a length of the Dryer shell 18 is limited. The closed zone 16 fills low pressure steam, a condensate,

009823/096 6

Air or water flows out of and into the remainder of the drying roll 12, high pressure steam, air or any other suitable Insulating medium can either be directed into and out of the roller end zones or when installing the partition wall arrangement 10 in these zones are included. An adjustment device 20, best shown in FIG. 2, may be used as part of the bulkhead assembly 10 and closes the end of the closed zone 16, the opposite of the roll face lies. This device 20 is formed from a plurality of threaded rods 22 and clamping devices 23, in order to hold the partition arrangement 10 in relation to the roller end face 14 in the installed position. The directional arrow near the with Threaded rod 22 illustrates the direction of movement the device 20. The device 20 is also with inner and outer sealing means 24, 26 are provided by means of which the closed annular zone 16 between the dryer shell. 18 and the partition arrangement 10 can be sealed at the end 'which is opposite the roller end face 14.

The end of the bulkhead assembly 10 is best shown in FIGS. As can be seen in these, there are two clamping rings 28 and 30 suitably split and having interlocking flanges 32,34 between the bulkhead assembly 10 and the cylindrical wall of the dryer roller 12 is arranged. These rings 28, 30 close, as noted above, the The end of the closed zone 16, which is opposite the end face 14 of the roll. The rotatable gev / inde bars and their associated nuts allow the adjustment that is necessary for the longitudinal adjustment of the rings 28 and 30, and the rods are also provided with suitable securing means at their ends. In addition, there are additional guide rods 35 which guide the partition assembly 10 within the body of the drying roll 12. A sheet-like body 36 can insulate the longitudinal wall of the partition arrangement 10 against the fact that this is in direct contact with the hot high-pressure steam

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comes. The gap or space between the bulkhead assembly and the sheet-like body thus creates airborne damage insulation between a hot and cold chamber.

It should be noted that a partition arrangement: in near one end of a drying roll and that one or more other such devices can be incorporated into the roll can be installed in order to obtain adjacent zones near the roller ends, in which predetermined temperature values are achieved through the use of low-pressure steam, condensate, air, Water or any other heating or cooling medium can be achieved. The installation of more than one partition arrangement in the vicinity of one end of the roll is therefore within the scope of the invention.

008823/0966

Claims (4)

Claims 1. Method of! Drying a web-shaped material under Using a rotatable trooken roller, the end faces and having a coat and overdrying along at least one side edge of the sheet material is reduced, marked you raw housing and setting a partition wall arrangement inside the roller whose longitudinal axis near at least one end of the roller, um, one to form a substantially closed zone, which is limited by the roller end face, the partition arrangement and the scantling introduction of low-pressure steam, condensate, air or water with a predetermined elevated temperature in the closed zone and introduction of pressure steam with a higher temperature in the rest of the roller, 2. The method according to claim 1, characterized in that the web material j-paper verv / ends. 3. Device for drying a web-like material and for carrying out the method according to claim 1, characterized by a rotatable troak roller with end faces and a dumbbell, a partition wall, which is arranged inside the roller along its longitudinal axis near at least one end of the roller, around a closed one. Zone train that through the roller face, the partition wallan ™ Order and the coat is limited, a device for a ~ carry low pressure steam, condensate, air or water in; this end zone and through a device sum introducing High pressure steam in the rest of the Walae «, BAD ORiGfNAL Qö IS2 3/08 0 g 4. Apparatus according to claim 3 »characterized in that the partition arrangement is arranged adjustably along the longitudinal axis of the drying roller and contains two Kleramringe, which have inner and outer sealing means to seal the closed zone between the jacket of the drying roller and the partition arrangement at the end, which is opposite the roll face. 009823/0966 Blank page