FI113689B - Seal for suction roll of paper or board machine comprises monitoring mechanism for monitoring wear of seal and comprising arrangement for determining need for replacement of seal based on information about wear of seal - Google Patents

Abstract

A seal for a suction roll of a paper or board machine comprises monitoring mechanism for monitoring the wear of the seal, the mechanism comprising an arrangement for determining the need for replacement of the seal based on information about the wear of the seal without interrupting the operation of the suction roll. A seal for a suction roll of a paper or board machine, the seal being placed inside a rotating shell (21) of the suction roll and having a system for monitoring the wear of the seal (22) disposed in connection with the seal, comprises monitoring mechanism for monitoring the wear of the seal, the mechanism comprising an arrangement for determining the need for replacement of the seal based on information about the wear of the seal without interrupting the operation of the suction roll.

Description

113689

BACKGROUND OF THE INVENTION The present invention relates to a seal for a paper or board machine suction roll which is disposed within a rotating roll diaper of the suction roll, the seal of which is provided with an abrasion seal, continuously, the gasket of which is monitored by means of a tracked measuring device providing continuous information on gasket wear.

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In paper and board machines, the vacuum zone suction box vacuum zone is sealed against the inner surface of the diaper with side and end seals. The seals are worn due to the abrasive contact of the seal with the inner surface of the diaper, so that the seals have to be periodically replaced, for example, when servicing a suction roll or servicing a paper machine 15. Because the seals are inside the rotating roller casing, their wear level is difficult to check / measure while driving. Too much gasket replacement is unnecessary and too long driving time for the gasket can cause roller runnability problems, such as achieving sufficient vacuum pressure .. can cause problems and even lead to very harmful and expensive kite stoppages (· t 20 when suction roll vacuum is lost when the seals are no longer functional »<• · * ·.

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• * · • * · ,,,.: In practice, the need to replace seals has been based on the needs of each paper or board • •. ' Experience with roll gasket replacement intervals and in determining such gasket replacement intervals, the determinant factor for roll roll maintenance intervals varies according to the application of different rolls, for example, a former roll roller usually has a wire stocking that is serviced during rollover. it is specifically the side seal> ...,: wear. The amount of wear / speed is a very roll-specific and difficult-to-determine property. The most problematic is defining a new »! date of first roll maintenance, as practical historical information on the 2 113689 factors of wear does not exist. It is only after the first maintenance that the properties of the roller have been found e.g. wear rate of seals. The wear parameters of the suction roll gaskets are also affected by the operating parameters of the roll. For example, if the driving pressures are changed, the wear rate of the seals will also change. This is one of the makers, which further complicates the determination of the roll maintenance date.

One prior art arrangement of a side seal wear indicator is disclosed in U.S. Patent No. 5,746,891. In this known arrangement, the wear of the side seal is checked when the roll / machine is serviced. The side seal is provided with wear indicators, such as materials of different colors embedded in the recesses formed in the recesses of the recesses, to indicate how far the seal has worn out or the gauge is provided with a scale showing how far the wear has progressed. In addition, this US Patent discloses an application example in which 15 conductors are shown in connection with the gasket, which are connected to the indicator lights and the power supply. When the insulation is worn, an electrical circuit is formed: the lights, the power supply, and the water that comes in contact with the electrical conductors, which causes the indicator to light up when the seal is worn. The problem with the arrangements shown, however, is that the wear condition of the side seal will not be known until: 20 the roller is otherwise stopped for servicing and even the light-stained information • f> «· *».:. is obtained only when the indicator light is on, when continuous data • a> t. '. : Gasket wear status not obtained.

International Application Publication No. WO 00/43592 discloses a side seal comprising indicator means which are continuously, directly or indirectly tracked: '·: to provide a measure of the remaining wear of the seal or the wear of the seal. In the embodiment disclosed in the publication, a gasket is imitated; a sensor that measures its distance from the surface of the roll shell and provides information about the gasket; snow-covered. The problem with this known solution is that the sensor is positioned. 30 movable seals and takes up a lot of space. In addition, seal replacement; the sensor (s) must be reinstalled. The sensor is also disposed within the wear part, i.e. the gasket itself, whereby the gasket and sensor may be caught by the gasket during the gasket, if gasket replacement operations have not been timely performed. The side seals of the suction rolls extend along the length of the roll, and thus, if information is required on the wear of the side seal in the longitudinal direction of the roll, that is, the transducer, several sensors must be positioned side by side.

The object of the invention is to provide an arrangement for obtaining information on the wear of the suction roll gasket 10 in which the above problems have been eliminated or at least minimized.

To achieve the above and later objects, the paper or board machine suction roll seal according to the invention is essentially characterized in that the seal wear device is attached to the fixed frame structures of the suction roll suction box.

According to the invention, the device measuring the suction roll gasket of a paper or board machine is located in connection with the fixed: *, body part of the suction roll suction box, e.g. in the gasket holder, thereby providing considerable advantages over prior art arrangements. Such a structure is uni- • · * · • j. simple and inexpensive, since you do not have to take into account the requirements of a moving part when installing a measuring device. Thus, in the wear monitoring system according to the invention, there is also no risk of a device measuring, e.g., sensor: "": hitting the sheath. The wear indicator 25 of the suction roll seal according to the invention is simple to construct and small in size. It is also particularly suitable for use with · · 'lockable seals, since the measuring device, eg sensor; ,,.: Is in the body of the suction box. The installation of the abrasion slider fitted to the seal of the suction roll according to the invention is easy because it does not require special action when changing the seal because the measuring device is attached to a fixed part: 30 e.g. a seal holder which does not have to be replaced.

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In a preferred embodiment of the invention, the measuring device uses a counter piece mounted in the seal, whereby the measuring device thus measures the distance of the fixed part to the movable part (counterpart). This application is also suitable for use with lockable seals, since only the counterpart is located in the movable part, i.e. the seal. Further installation is easy, because when replacing the gasket, only the counter piece should be attached to the gasket, unless it is already pre-installed, which is also possible.

In a preferred embodiment of the invention, the sensor used is a measuring device which moves along the wear surface, for example in a spring-loaded manner, thereby indicating a wear event. In this exemplary embodiment of the invention, no separate counterpart is required.

Another advantage of the invention is that when the measuring device is not mounted on the gasket itself, it is easy to adapt it to different types of gasket applications and, furthermore, the placement of any sensor wires does not cause problems since the wires are not connected to the moving part.

; The measuring method used in connection with the invention may be, for example, electrical, inductive, mechanical, pressure-based, optical or the like.

• | The wear monitoring system according to the invention can be implemented in different types: with measuring applications, a sensor mounted on the suction box body can measure distances from different surfaces and, of course, with an application in which different measuring counter arrangements are provided:

The invention is also suitable for use in connection with lockable seals and as required; At 30, the control of the lockable seal can be combined with the measurement so that when the seal is moved, the locking sequence is repeated to release the seal from the jacket. If necessary, the measuring arrangement can also be combined with a temperature measurement.

In the following, the invention will be described in more detail with reference to Figure 5 of the accompanying drawings, the details of which, however, are not intended to be narrowly limited.

Figure 1 schematically illustrates an embodiment of the invention.

Figure 2 schematically illustrates another embodiment of the invention.

Fig. 3 shows an embodiment of the invention which does not use a counterpart of a measuring device.

Figure 4 shows some alternatives for the distances to be measured in accordance with the invention for monitoring seal wear.

As shown in Figure 1, the suction zone (s) of the suction roll suction box are sealed. , for pressing the roads 22 against the inner surface 21 of the roll shell, there is a seal holder 25; .20 a loading hose (s) 26 disposed beneath the seal, that is, on the other side of the seal 22, relative to the inner surface of the jacket 21, to which the pressure is applied; 11 gaskets 22 are pressed. Within seal 22, pressure in the load line 26 may •; if necessary, to maintain the sealing effect of seal 22.

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In accordance with the embodiment shown in Fig. 1, a suction roll system is provided with: · a system for continuously measuring the level of wear of the seal 22.

; t · * The measuring device 23, e.g., the sensor is mounted fixedly to the fixed body of the suction roll suction box, e.g., to the holder 25 of the gasket 22 and the measuring device 23 t, to measure the distance to the gasket 22, e.g. 30 when the gasket 22 is initially loaded with the casing 6113689 21, the measurement is reset, the wear of the gasket 22 being detected by the change in position of the mating member detected by the measuring device 23.

The application shown in Figure 2 is particularly well suited for use with narrow gaskets, but can of course also be used with wide gaskets. In Fig. 2, parts corresponding to Fig. 1 are used with reference numerals. The measuring device 23 is used to measure the distance of the mating member 24, preferably a magnetic metal mating member, to provide continuous wear information of the gasket 22. The measuring device 23 is attached to the holder 25 of the seal 10, which is like a figure fixedly connected to the body of the suction box in Fig. 1.

The wear indicator stroke measurement application of Fig. 3 employs a sensor which, e.g. In Fig. 3 the same reference numerals are used for the parts corresponding to Figs. 1 and 2. The measuring device 23 is a sensor provided with a loading member 27, for example a spring-loaded member, whereby the measuring device 23 moves along the surface of the wear seal 22 and thus obtains information about the wear event based on the movement S.

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As shown in Figure 4, the wear indicator arrangement can be implemented in different types of M i t. ·. ; measuring applications and a measuring device attached to the suction box body e.g.

By means of a sensor, distances from different surfaces can be measured and, of course, different measuring counterparts can be composed of many different types or a measurement application, for example, a sensor that does not require a counterpart at all, can be used. Figure 4 shows some possibilities. The numbers in the circles of Figure 4 'illustrate the various measurement alternatives described below. By pressing the seal 22 to the bottom, i.e. against the side surface of the sheath 21, it is possible to: measure the distances between points 1-3 or 2-3 to obtain information on the wear of the seal. 30 Mass. Further, the distances 2-4, 2-5, 2-6, 5-9, 6-9, 7-8, 10-11, 7113689 10-6 can be measured. This provides information on the wear of the gasket as the distances change as a result of wear.

Although Figures 1 to 4 illustrate embodiments of the invention in connection with suction roll side seals 5, the arrangement of the invention is naturally applicable to the end seals in accordance with the above principles.

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Claims (11)

A seal for a paper or board machine suction roll, disposed inside a rotating roll mantle (21) of a suction roll, the seal of which is provided with a seal (22) wear monitoring system comprising means (23, 24; 27) a seal (22). to monitor continuously the wear of which the gasket (22) is connected to the fixed frame structures of the suction roll when the gasket (22) is continuously connected to the wear of the gasket (22). Suction roll seal according to Claim 1, characterized in that the measuring device (23) is attached to the side seal holder (25). Suction roll gasket according to Claim 1 or 2, characterized in that the means (23, 24) for monitoring the wear of the gasket comprises a socket (24) connected to the gasket (22), wherein the gauge (23) measures the socket (22) 24) location or relationship; *, the continuous distance about the wear of the gasket (22) is obtained from the teats. i 20 ·. Suction roll gasket according to Claim 3, characterized in that the counterpart (24) is mounted on the side opposite to the wear surface of the seal (22). • · • · • i » Suction roll seal according to Claim 3 or 4, characterized in that the measuring device (23) is an inductive sensor and the counter body (24) is made of magnetic metal. Suction roll gasket according to claim 1 or 2, characterized in that; The means (23, 27) for monitoring the wear of the seal (22) comprise a spring loading member (27) adapted to move with the wearable 113689 surface of the seal (22) to provide continuous measuring wear of the seal (22). Suction roll gasket according to claim 1, characterized in that the means for monitoring the gasket wear are based on the measurement of the electric distance. Suction roll gasket according to claim 1, characterized in that the means for monitoring the wear of the gasket are based on the measurement of the mechanical distance 10. Suction roll gasket according to Claim 1, characterized in that the means for monitoring the wear of the gasket are based on the measurement of the distance by pressure. 15 Suction roll seal according to claim 1, characterized in that the means for monitoring the wear of the seal are based on optical distance measurement. ; . ·, 20 A suction roll gasket according to claim 1, characterized in that the intermediate sealing means are arranged to monitor the wear of the seal. '. : to work. »* · *» »> * 10 1 13689