FI86898C - Method and apparatus for controlling the lip cone in the inlet box of a paper machine - Google Patents

Description

86898

Method and apparatus for adjusting the lip cone of a paper machine headbox Förfarande och anordning för regiering av 5 läppkonan i inloppslädan av en pappersmaskin

The invention relates to a method and a device for adjusting the lip cone of a paper machine headbox 10.

Methods for adjusting the top lip bar of a paper machine headbox and in particular the top lip bar top list are known from the prior art. For example, U.S. Patent 4,551,204 discloses a paper machine headbox lip cone-15 for adjusting the upper lip bar by lever mechanisms. The upper lip beam is formed of an articulated structure, the parts of which are movable relative to each other to adjust the mass volume of the lip cone to obtain the desired flow properties. FI patent application 771467, on the other hand, discloses a pulp wire supply device in which the pulp liquid dispensing device comprises a rather large number of distribution channels through which the pulp flow is conveyed.

The manifold system is provided with stepped extensions as well as a nozzle channel bounded by side walls that taper in the flow direction.

25 Hardware solutions are known in the art in which the top strip of the headbox top lip bar alone can be adjusted. In this case, when adjusting the position of the tip strip, the constriction coefficient of the flow also changes, because the distance of the tip of the tip strip from the surface above the lip cone changes and thus the flow conditions change.

30

However, the known solutions do not provide a universal solution for adjusting the shape of both the tip strip and the lip cone and in such a way that said shape can be maintained even at high flow pressures.

35 In order to make the mass flow as uniform as possible for all mass qualities, the mass flow must be adjustable and thus the lip cone of the headbox and the tip strip of the lip cone must also be adjustable. It would also be advantageous for the shape of the lip cone and the flow volume of the lip cone 2 86898 to be adjustable also in the transverse direction of the paper web.

In the invention, it has been realized to form a headbox of a paper machine such that the headbox comprises a lip cone comprising an adjustment plate abutting the lip cone above. The end of the adjustment plate comprises a tip strip for adjusting the flow gap of the lip cone. According to the invention, a control plate is used which is controlled by a separate actuator, preferably a control cylinder. The adjusting cylinder is connected to the tip strip portion of the adjusting plate 10 via a rod. Above the control plate there is a liquid space to which the same pressure is set as the mass in the lip cone. Therefore, no stresses and deflection forces are applied to the control plate. According to the invention, by changing the volume of the liquid space, the deflection shape of the control plate and thus the volume 15 of the lip cone and thus indirectly through it the mass flow from the lip cone can be changed.

The change in the height of the lip cone can again affect the flow orientation in the desired way.

20 By bending the adjusting plate from the front edge with the adjusting rods, the tip of the tip strip can be freely shaped without changing the constriction coefficient of the tip of the tip strip, since the adjustment only changes the distance of the tip strip from the lower lip beam. The adjustment does not in any way affect the geometry of the tip strip and the associated adjustment plate. Thus, the constriction coefficient of the flow remains constant at all control stations.

The method according to the invention for adjusting the lip cone of a paper machine headbox is mainly characterized in that the method produces a pressure corresponding to the pulp flow of the

86898 3

The device according to the invention for adjusting the headbox of a paper machine is mainly characterized in that the device comprises, in connection with the control plate, a liquid space into which pressure can be applied.

The invention will now be described with reference to some preferred embodiments of the invention shown in the figures of the accompanying drawings, to which, however, the invention is not intended to be exclusively limited.

Fig. 1A shows a headbox lip cone 10 adjusting apparatus according to the invention in a cross-sectional view.

Figures 1B and 1C show different embodiments of the tip of the flexible plate portion of the control plate.

15 Figure 2 shows the apparatus of Figure IA, Figure IA arrow K direction of a papermaking machine as seen from the machine direction.

Fig. 3A shows an embodiment of the invention in which the liquid space in connection with the adjustment plate is divided into blocks over the entire width of the upper lip, whereby by changing the adjustment pressure 20 the shape of the adjustment plate can be influenced at the desired lip cone width.

Figure 3B shows an embodiment of the invention in which the liquid state is; uniform across the width of the lip cone.

:: 25

Figure 4 schematically shows a liquid space filling and pressure compensation arrangement.

Figure 1 shows a lip cone according to the invention in cross-sectional view. The adjusting rod 10 is connected to the front end of the flexible plate part 14 of the adjusting plate 11 according to the invention. The adjustment plate 11 comprises a body part 12 to which the actual flexible plate part 14 is connected. At the front end of the plate 14 there is a square or rectangular body portion 15 comprising, in this embodiment of the figure, a protrusion 16 of the tip-35. which seals the fluid space 17. The entire body 18, i.e. the lip beam 18, is movable by cylindrical devices 19 with the body 18 being pivotable on a hinge point 20 relative to the rest of the body structure 21. In the headbox according to the invention, the volume and flow gap of the lip cone itself are adjusted by moving the control rods 10. By means of the control rod 10, e.g. by acting on the actuator 22, the front part A of the control plate 11 is moved downwards and / or upwards and thus the control plate 11 is bent. In order for the adjustment 10 to be stable, the same pressure as in the lip cone K is adjusted to the space 17.

Fig. 1A shows a dashed line of a deflection of the control plate 11.

15

Fig. 1B shows the tip portion 16 of the adjusting plate 11 of Fig. 1A on an enlarged scale.

Figure 1C shows an embodiment of the invention in which the adjusting plate 11 does not comprise a tip.

In Figure 2 is shown in Figure IA to the headbox of Figure IA as seen from the direction of the arrow K, or machine, direction. The apparatus comprises a plurality of spindles 10a, 10b and a plurality of actuators 22a, 22b thereon. Thus, by adjusting the spindles 10a, 10b ... (arrow Lj), the deflection of the control plate 11 and thus the position of the tip A of the control plate 11 at the desired points in the width direction of the track can be influenced.

Figure 3A shows an embodiment of the invention in which each adjusting arm 10a, 10b corresponds to its own liquids 17a, 17b. In the embodiment, the shape of the lip cone K of the headbox of the paper machine can be changed in the desired direction in the width direction of the web. Thus, the desired amount of liquid can be introduced into each desired liquid space 17a, 17b, 17c ... and a deflection of the desired shape can be obtained on the control plate 11. Thus, different amounts of liquid can be introduced into the liquid spaces 17a, 17b 35. Thereafter, the liquid pressure of each liquid space 17a, 17b of 86898 5 is adjusted to be equal to the pressure of the mass flow in the lip cone K at each liquid space 17a, 17b.

Figure 3B shows an embodiment of the invention with only one liquid space 17 over the entire width of the web. This solution provides an adjusted K-shape of the lip carton. However, for each adjustment of the fluid space 17, this shape is constant over the entire width of the track.

Figure 4 illustrates the control of the mass flow 10 according to the invention. As shown in Fig. 4, the pressure of the lip cone is measured and a pressure corresponding to the pressure of the lip cone K is brought into the liquid space 17 of the control plate so that the control plate 11 and in particular its plate part 14 remains in the desired shape. To change the deflection shape, a larger or smaller amount of fluid is introduced into the fluid space adjacent to the control plate, and then a pressure corresponding to that in the lip cone is adjusted to that space. Thus, according to the invention, both the amount of liquid entering the liquid space adjacent to the control plate and the pressure of said liquid space are detected, and correspondingly the pressure of the lip cone is detected by sensor devices.

20

According to the invention, however, the main adjustment is performed by moving the adjusting spindles 10a, 10b ... and bringing them to the desired position, whereby the tip A of the adjusting plate 11 or the tip projection 16 is at the desired distance from the lower lip beam P. Thus, a separate setpoint can be set for each control rod 10a, 10b ... depending on what is desired to be the size of the flow gap R of the lip cone K at that control rod and / or the volume of the lip cone at that control spindle. Correspondingly, 30 (if the apparatus corresponds to the embodiment of Fig. 3A) the liquid spaces 17a, 17b ... associated with the control plate 11 can be adjusted individually. Different pressure blocks 17a, 17b, 17c ... are formed, whereby the desired shape of the lip cone K is obtained, which is determined by the amounts of liquid placed in the different liquid spaces 17a, 17b ... and also by the control spindle 10a, 10b acting on each liquid space 35 17a, 17b . instead of.

6 86898

The pump device 23 produces the desired amount of liquid and pressure in the space 17a. The adjustable pressure valve 24 adjusts the space to a pressure according to the set value C, which is preferably the same as the pressure measured in the lip cone K measured by the sensor device 25.

Claims (8)

A method of controlling the lip cone (K) in the inlet carriage of a papermaking machine, using a method of using spindles (10a, 10b, 10c ...) with a functional device (22), connecting the ends of the spindles to the a control disk (11), wherein the control disk (11) in the method bends to a position which performs a desired shape on the lip cone, characterized in that in the process a pressure is produced in the liquid of the liquid space (17) on the opposite side in the relationship. to the pulp flow space of the lip cone (K) of the control plate (11), which corresponds to the pressure on the pulp stream (M) of the paper machine, the control plate (11) being kept in the desired constant position so that the pressure of the pulp stream does not increase moving on the control plate (11). . 15 2. A method according to claim 1, characterized in that in the process, such a quantity of liquid is produced in the liquid space (17) which performs a desired bending form on the control plate (11) and thereafter the liquid pressure in the liquid space (17) is adjusted to be in the same the pressure on the mass flow in the lip cone (K). 20 3. A method according to any preceding claim, characterized in that there are several separate liquid spaces (17a, 17b ...) in the process advantageously in connection with each control spindle (10a, 10b), and a fluid space (17a, 17b, 17c ...) can bring different amounts of fluid, whereby by changing the amount of fluid and / or by moving the control spindle (10a, 10b) at the liquid space, the desired shape of the lip cone (K) can be controlled. the width of the lip cone. 1 2 3 4 5 6 Apparatus for controlling the lip cone (K) of an inlet carriage in a 2 paper machine, the device comprising a control disk (11), the 3 control spindles (10a, 10b, 10c ...) being connected to the front end of its 4 flexible disk part (14), whereby by changing the position of rules 5 the spindles (10a, 10b ...) bend the control disk (11) in a position which performs 6 a desired flow gap (R) in the lip cone (K) and / or to a position which performs a desired internal shape of the lip cone (K), characterized in that the device comprises a liquid space (17) in communication with the control plate (11), which can be pressurized. 5. Apparatus according to claim 4, characterized in that the control plate (11) comprises a body part (12) to which the flexible disk part (14) is connected. 6. Apparatus according to claim 4 or 5, characterized in that in the anterior end of the disc (14) there is a tip projection (16) which determines the flow gap (R) in controlling the position of the control spindles (10a, 10b). . Device according to any one of the preceding claims 6-9, characterized in that a liquid space (17) is formed between the body parts (12 and 15) of the control plate (11), to which a liquid can be conducted under pressure and which liquid space (17) is limited to an upper body (18), the edges of the body (18) having seals (19a, 19b) which seal to the liquid space (17). Apparatus according to any one of the preceding claims 4-7, characterized in that the device comprises several separate liquid spaces (17a, 17b, 17c ...) over the width of the lip cone (K), whereby each liquid space is provided. (17a, 17b, 17c ...) can introduce the desired amount of liquid and to each fluid space (17a, 17b, 17c ...) one can regulate a pressure of the desired size, whereby by applying the other amount to the liquid volume in the liquid spaces can control the shape of the lip cone (K). Apparatus according to any one of the preceding claims 4-8, characterized in that the installation arrangement comprises liquid insertion means, advantageously a pump (23), by means of which the desired amount of liquid is regulated in the liquid space (17). the control plate (11) and that there is a pressure control valve (24), by means of which one can determine the desired pressure for the liquid of the liquid space (17) and that there are sensor means (25) by means of which the pressure can be measured on the mass flow of the lip cone (K), whereby on the basis of said measurement data it is possible to regulate the pressure of the liquid of the liquid space (17) to the same level as the pressure of the mass flow nun.