FI86095C - PRESS RELEASE TORKNING AV EN PAPPERSBANA. - Google Patents

Description

1 86095

Press for drying the paper web

The invention relates to a pressing apparatus for drying a web of material, for example a paper web, in which the device has a flexible tubular jacket rotating around a non-rotating guide body, which can be pressed by at least one press-fitting press With the web of material to be dried on the counter roll.

Such press devices are known, for example, from DE-33 17 455, DE-33 11 998, US-4 287 021 or GB-2 057 027 and are used, for example, in the press section of a paper machine 15 or for drying some other web of material. In addition, the paper web becomes dried to a certain extent mostly together with at least one water-absorbing web, e.g. an intermediate felt, in a compression area reaching a certain circumferential part of the counter roll between the counter roll and the compression shoe 20 due to pressure from the compression shoe. Between the press shoe and the paper web, or felt, is a movable tubular sheath that is passed over the guide piece. Thus, at least, a stress-free and tight rise of the jacket over the guide piece is approached. The pu / y 25 crossing shoe is supported against the support, whereby a pressure space is formed between the press shoe and the support, which is provided with a suitable pressing medium to provide the desired pressure of the press shoe on the counter roll and the paper web to be dried.

30 Such a pressing device is required, on the one hand, to ensure easy entry and exit of the jacket over the edges and corners of the press shoe and, on the other hand, that the friction between the guide and the jacket does not become too great, so that heat generation is required. the thrust of the sheath is low. The guide piece 2 86095 must therefore be in such a position that certain circumferential tolerances in the circumferential direction, which can be of the order of 1% of the total length, are equalized. In this case, however, there must be good control. To prevent vibration of the tubular shell, this must be tensioned in the axial direction and firmly attached to the side plate.

Another problem with the press device is related to the support shoe supported against the support and the guide piece when opening the press device, e.g. due to felt change or emergency, e.g. in case of felt cracking or paper web winding, so that the press device has to open so much 40 times between the jacket and the counter roll. -50 mm spacing, and the pressing device or jacket is placed in the next position on the corresponding roller. The opening and closing of the pressing device must then take place quickly, safely and with as little power and energy consumption as possible. The crimping device must also be properly accessible when the crimp gap is open.

20 Other problems are that the guide must not get or fall, and there must be no deviations in the casing. In addition, when different lengths are used in the shoes, the pitch of the guide must be adjustable to ensure a smooth entry and exit.

However, in previously known *: * pressing devices such as those mentioned above, these problems have not been solved or have been solved in the incomplete pressing device known from U.S. Pat. No. 4,287,021, the shape of the guide piece being unchanged, so that it is not possible to equalize the circumference of the jacket. .

The guide piece is connected to a support, opposite which the shoe of the pressing device moves in the pressing direction. Precise control of the casing over the guide piece and at the same time over the clamping shoe is thus hardly achievable. To open and close the press-35, the entire set, including the sturdy bracket, guide and press shoe, must bend simultaneously, for example with the support of the bracket or the upper roller bearing pins, which means significant power and energy consumption.

5 DE-A-31 02 526 discloses another pressing device with a pressing shoe which is hydraulically pressed between a jacket and a support or guide piece. The support piece is further supported on the support hydraulically. In order to open and close this compression device, the pressure in both pressure spaces between the press shoe and the guide piece on the one hand and the guide piece and the bracket on the other must be precisely determined relative to each other, or otherwise open and closed according to the top roller. 15 Due to the considerable mass of the control device or the upper roller, the time, force and energy consumption required to open and close the pressing device is also in no way optimal here and requires adjustment equipment which can cause damage. In addition, the press shoe does not pivot 20 sufficiently with respect to the support piece so that a sufficiently precise inlet and outlet of the paper web is not adjustable and the desired change is not possible.

DE-A-33 11 996 further discloses a pressing device in which the support body has a pressing - *: · two radially movable diapers - near the 25 shoes. It further describes the axial prestressing of the lateral sealing plates of the jacket, which, however, does not allow any movement in the compression direction.

It is an object of the invention to obviate the above-mentioned disadvantages of the prior art and in particular to improve the transfer of the jacket over the guide and the press shoe in a pressing device as described above, thereby reducing friction, smoothing the jacket circumference, avoiding jacket vibration, and enabling the press power and energy saving opening and closing -, * ··. misen.

This object is achieved according to the invention in that at least one device is provided for changing the outer diameter of the guide piece in order to equalize the tolerance of the circumference of the sheath.

This preferably consists of a single stretching rod, the guide body having a plurality of mutually movable parts which are made to expand or move relative to each other, the circumference of the guide body fitting around the circumference of the casing.

In the axial direction, it may be advantageous to have an additional fastener to keep the jacket always in the desired shape, which at the same time allows axial tension of the jacket as well as movement in the compression direction.

It may be advantageous for the control device to be movable and adjustable, separate from the compression shoe, so that the height of the control body relative to the compression shoe can be set at the optimum inlet opening. Thus, in the adjustment step, the support piece and the side plates are next placed and only then the press shoe is used.

The invention will be explained by means of an exemplary embodiment shown in the drawings, whereby other advantages of the invention will become apparent. The pictures are:

Fig. 1 shows a longitudinal section of the rest of the pressing apparatus, * · * Fig. 2 shows a cross-section of this pressing apparatus, Figs. 3-5 show cross-sections of different modifications of the pressing apparatus, Fig. from the end of the second pressing device, ·. Fig. 8 shows a cross-section of this second crimping device, Fig. 9 shows a section of the crimping device. of the pan, and Fig. 10 shows a cross-section of the second compression member.

In the pressing device shown in Figs. 1 and 2, the pressing part 1 acts with the counter roll 2 along the felt 3 on the paper web 4, or other web of material to be dried, inserted into the pressing gap between the pressing part 1 and the counter roll 2. The counter roll 2 is a substantially fixed, closed or hollow roll or bending smoothing roll.

The pressing part 1 has a fixed support 5 surrounded by a flexible tubular sheath 6. This sheath may be made of rubber, which may be optionally reinforced with a textile or steel fabric, or it may be made of a suitable elastomeric plastic. Inside the jacket 6 there is at least one pressing shoe 7 supported against the support 5 15 by means of a pressure chamber 8 filled with a suitable pressing medium such as oil, water or emulsion so that this pressing shoe 7 presses the pressure of the pressure chamber 8 against the counter roll 2 and thus presses the paper web 4 stick and dry it.

The clamping shoe 7 can be a single axial strip-shaped support shoe supported by a single strip-shaped pin in the groove-shaped pressure space 8 of the support 5, or axially individually tightly pressed separate clamping shoes 8. the axial through-going press shoe may also be supported on a plurality of pins and a plurality of pressure spaces.

The upper surface of the pressing shoe 7 has a shape corresponding to the shape of the counter roll 2. In this way, an elongated pu-. . the crossing zone P for drying the paper web, whereby the "·" drying effect can be considerably improved compared to the known pressing parts having two rigid rollers. In order to achieve this advantageous effect, the jacket 6 surrounding the paper web 4 and the felt 3 with the counter roll 2 must be flexible enough to fit the shape of the counter roll 2 in the pressing zone P.

The support surface of the press shoe 7 may have pressure pockets 9 connected by holes to the pressure space 8 in the same way as in hydrostatic support pieces, as is known from bending compensating rollers, for example in U.S. Pat. No. 3,802,044. The press shoes 7 may of course also be made in other ways. for example as a hydrodynamic support shoe according to U.S. Patent No. 4,287,021. 10 In order to ensure an easy entry of the jacket 6 into the pressing zone P as well as an easy exit from this zone, it is expedient to shape the edges of the pressing shoe 7 accordingly, for example to round them.

In order to achieve a smooth passage of the jacket 6 through the compression zone P 15, the inside of the jacket 6 has a non-rotatable guide piece 10, over the outer side 11 of which the jacket 6 can slide at least almost without tension and tightly. The lowest possible stress is desirable here in order to avoid friction losses and to keep operating power low. 20 On the other hand, the casing must also not be too loose, that is to say, it must not have too much room for movement, thus avoiding the risk of vibration and damage in the case of very high speeds of modern paper machines.

To reduce the frictional force, the outer side 11 of the guide piece is made in the shape of a polygonal triangle so that the sheath 6 passes only over these edges. In order to ensure a smooth passage of the sheath 6 over the outer side 11 of the guide piece, it is advantageous if the number of angles of the rim is of the order of 10 to 20. Small amounts of compression medium can pass through the hollow space formed between the angular outer side 11 of the guide piece and the tubular sheath 6 so that good lubrication can be achieved and thus only slight friction occurs. To keep the excess compression medium away, there is a compression body near the compression body -. * ··. near the outlet of the feeder 12.

7 86095

The inner part of the guide piece 10 is shaped so that it can slide in the compression direction along the support 5 so that, however, transverse movement is avoided. The press-shoe side portion 13 of the guide piece of the guide piece can be fixed to the structure of the press-shoe 7 so that the entire guide piece can move in the pressing direction only together with this press-shoe. As the pressure decreases in the pressure space 8, both the pressing shoe 7 with all parts of the shoe and the sheath 6 move simultaneously against the pressing device 10, while the support 5 remains in place. When the maximum rise height is 40-50 mm, the pressing device can thus be opened without having to move the heavy support 5, and the pressing device can thus be closed again with low energy consumption. When the relative position of the pressing shoe 7, the jacket 6 and the guide piece 11 remains unchanged during the opening and closing of the pressing device 15, the jacket tension remains almost the same during this process, so that the smooth running of the jacket is maintained even when the pressing device is open.

However, it may be advantageous for the pressing shoe 7 to move independently of the body 11, if necessary. When closing the pressing device, the guide piece 11 can then be moved to the next adjustable position 25 and only then can the pressing shoe be moved, whereby a smooth and optimal travel is achieved.

In normal use, the jacket 6 is passed through the counter roll 7, the paper web 4 and the felt 3 and pushed shut. In order to avoid slipping of the jacket and the resulting tension, and to secure the jacket 6 even when the pressing device is open, what is the closing of the pressing device. . facilitate, as shown in Figure 1, the sheath • · · may have an optional auxiliary use. At the end of the jacket 6 there is a sealing ring 14 which, together with the sealing plate 15, acts on the support pin 16 of the support 5 and seals the outside of the inside of the jacket 6, but still allows the jacket 6 to move in the compression direction. Between the annular plate 14 of the jacket 6 and the plate 15 of the support 5 there is a ball bearing 17 which allows the jacket 6 to rotate around the support 5. The annular plate 14 has a toothed ring 18 on the inside, which is gripped from the outside 5 by a gear 19 on both sides of the shell 6, by means of which wheels the shell 6 is made to rotate with low energy consumption.

In order to allow a tolerance of the circumference of the jacket, which can be of the order of 1%, as well as changes in the circumference of the jacket during use, the guide piece is made so that a tight passage is guaranteed and maintained with the least possible tension.

In addition, as shown in Fig. 2, the guide piece is divided into a plurality of parts connected to each other by a person 20 so that stretching of the guide piece and thus fitting of the outer circumference is possible. This can take place, for example, by having a variable spacer 22, for example a spring or a pressure hose, between the two outer arms 21 of the guide piece. In this case, even a small force 20 is sufficient to prevent the casing from moving and vibrating without disturbing the casing disturbingly and thus increasing the friction. In the embodiment according to Figure 2, when the outer surface 11 is polygonal in the shape of a polygon and has a number of axial angles, other shapes may also be preferred.

Fig. 3 shows a guide body with longitudinal, wedge-shaped grooves 23 on the outer surface. Here, too, the jacket 6 passes through a sufficient number of contact points 24 so that a smooth passage is also guaranteed here. Furthermore, the entire guide piece 25 is attached to the press shoe 7, so that it can only move simultaneously and together. . with this against the bracket 5.

In the embodiment shown in Fig. 4, on the outer side of the guide piece 26, there is a number of axial steps 27, over which the jacket 6 slides. The guide piece 26 and 9 86095 the pressing shoe 7 can also be tightly fastened to each other here.

In the example shown in Fig. 5, the outer side of the guide piece 28 has grooves 29 instead, the operation being similar to that of the embodiments described above. To improve the lubricating effect, these grooves 29 may be attached to the lubricant dispensing opening 30. This is particularly expedient, if not necessary, with a small groove depth of the guide piece or a smooth copy of the ul-10. However, with a sufficient groove depth, a compression medium dripping into the compression part as a lubricant is generally sufficient to ensure a smooth passage of the jacket 6.

Instead of the axial direction, the grooves or steps on the outside of the guide piece can run obliquely, as shown in Fig. 6, for example. It has grooves 31 and 32 running helically on the outer side of the guide piece 11. In order to prevent different loading of the casing, it is expedient for the guide piece to have different helical screw lines on both sides. For example, in the example 20 shown, the grooves 31 are in the shape of a screw rotating to the right on the right side, while the grooves 32 are similar to a screw turning to the left on the left side. At the same time, it can be achieved here that the falling lubricant is automatically transported to both ends of the jacket, where si-25 may be needed.

In the example of the pressing device shown in Figures 7 and 8, the guide piece 10 is not attached to the pressing shoe 7. Instead, the support pin 16 of the bracket 5 has a hydraulic control cylinder 33 which operates independently of the pressure space 8 with which the pressing shoe 7 is supported on the support 5. . This adjusting cylinder 33 moves the levers 6 of the support 6 over the levers 34 with its side sealing plates 36 in the compression direction, and at the same time * also a guide 10 introduced inside the housing 6, such as: 35 also an inner sealing ring 38 acting with the fixed sealing plate 5.

10 86095

The pressure in the pressure chamber 8 and the adjusting cylinder 33 is regulated by a suitable device so that the movement of the jacket 6 and the guide piece 10 follows the movement of the pressing shoe 7 as desired. The movement of the press shoe is then analogous to the previous examples, i.e. either synchronous with the guide piece or it is also possible for the guide piece or the roller to be raised without the press shoe involved.

According to Fig. 8, the outer part 35, as shown in Fig. 4, has a number of axial steps 27, over the upper edge of which the jacket 6 passes. The number of steps must then be chosen to be large enough and the width of the intermediate space small enough to ensure accurate travel of the jacket. In addition, the steps 27 may be made slightly flexible in the radial direction 15 so as to be able to compensate for circumferential tolerances and changes. In addition, to compensate for the tolerance of the guide piece, the guide piece can be divided and spread.

In the form of the invention shown in Fig. 9, the fastening 37 of the jacket 6 opposite the sealing ring 36 at least at one end of the jacket 6 can be axially flexible. In the examples shown, the jacket 6 is screwed to the base 39 by a retaining ring 40. The base 39 has a pin or step 41 capable of sliding axially in a cylinder or slot 42 formed by an extension of the sealing ring 28. A disc spring package between both parts presses both - · '- thus weaves for tightening the sheath 6 in the axial direction. This measure improves the passage of the casing. More than 30 more.

The pressing part 1 shown in Fig. 10 has no control. . the pieces are not, as in Fig. 1, connected to the parts connected by joints, but to two opposite, laterally moving parts 101 and 102 which are pressed apart by the resilient parts 45, 35 46 and 47, so that here too 11,86095 the sheath the equalization of the circumferential tolerance and the smooth, frictionless and vibration-free course of the jacket are achieved.

Modifications and variations are possible without departing from the scope of the invention. Although it is advantageous, as in the embodiments described 5, to press the press shoe hydraulically against the counter-roller with a pressure space provided with a press medium between the support and the press shoe, other pressing methods can also be found for use. For example, the compressive force can be generated mechanically, e.g. by a suitable spring, electromagnetically or pneumatically. Also, the use is not limited to the drying of the paper web, but can in principle apply to all webs of material which can be dried by compression in a compression zone, e.g. textile webs. Corresponding applications, such as sizing or omitting or using other conveyor paths or wires instead of the general felt used in papermaking, are within the skill of those skilled in the art.

Claims (14)

1. Pressure device for dewatering a web of material, in particular a paper web, which device comprises about a non-rotating guide body (10,11,13) running flexible hose-like sheath (6), which is extensible by means of at least one inner man mounted, in the pressing direction, flexible, against a support (5) supported by a press (7) at a designated press zone (P) together with the material web (4) to be dewatered against a counter roll (2), characterized in that: for equalizing the tolerance of the circumference of the sheath (6), at least one device (22,44,45,46) is provided for altering the outer circumference of the guide body (11). 2. Pressing device according to claim 1, characterized in that the guide body (10,11,21) consists of at least two parts which are (22,44,45,46) movable relative to each other. Pressing device according to claim 2, characterized in that the clamping device (22,44,45,46) has flexible parts (44,45,46) or hydraulic, pneumatic or magnetically functioning parts. 4. Pressing device according to any one of claims 1-3, characterized in that the ends of the sheath (6) are fixed by means of sealing rings (36) and that a control device (33) is provided for displacing the men (6), -t. the sealing ring (36) and the guide body in the pressing direction. Pressing device according to any of claims 1-4, characterized in that the ends of the sheath (6) are connected to sealing rings, which can be pressed from the outside by tensioning devices (43, 47) in the axis direction. 6. Pressing device according to claim 5, characterized in that the control device (33) and the clamping device (47) are mounted at least almost in V: the same plane perpendicular to the carrier (5). , ·,: 35 Pressing device according to any one of claims 4-6, characterized in that the control device (86) (33) and on one side between the pressing boot (7) and the other such carrier (5) 1 are in each case at least one by means of pressure means provided with pressure chamber (8) so that the movements of the sheath (6) and the pressure boot (7) can independently follow each other. Pressing device according to any one of claims 1-7, characterized in that the pressing boot (7) is formed as a hydrostatic support body, the supporting surface of which shows a support pocket connected by a bore to the pressure space (8) between the carrier. (5) and compression boot (7) on opposite side. Pressing device according to any one of claims 1-8, characterized in that the outer surface of the guide body (25, 26, 28) has several corners (11) of a polygon prism or latch (23, 29, 30, 31) which have a axis-directed directional component, wherein the manifold (6) runs over the edges (24.30) between the steps (27) or the latch. Pressing device according to claim 9, characterized in that the latch (31,32) on the outer surface of the guide body (11) is in the form of a helical line. 11. Pressing device according to claim 10, characterized in that the running direction of the screw line (31,32) on one side of the guide body (11) is opposite to the running direction on the other side of the guide body (11). ··· 25 12. Pressing device according to any of claims 1-8, characterized in that the outer surface (35) of the guide body (25) has a radially extending step (27), over which the manifold (6) slides. 13. Pressing device according to claim 12, characterized in that the steps (27) are made flexible in a radial direction.