Sealing strip for a paper, cardboard or tissue machine made from a plurality of materials

Abstract

A sealing strip for a positive or negative pressure zone of a suction or blower roller of a machine for processing and/or producing web material, in particular a paper, cardboard or tissue machine. The sealing strip has a sealing face to be set against and in frictional contact with the inner side of a roller shell for sealing the positive or negative pressure zone during a rotational movement of the roller shell. The sealing strip has a lubricant channel in the form of a cutout from the sealing strip. The lubricant channel is arranged in front of the sealing face. The sealing strip is formed with a first material section at the sealing face and with a second material section at the front wall. The first and second materials are different in at least one physical property, such as modulus of elasticity, abrasion resistance, hardness, brittleness.

Claims

1. A sealing strip suitable for a sealing device for sealing a positive or negative pressure zone of a suction or blower roller of a machine for processing and/or producing web material, the sealing strip comprising: a front end side, a rear end side, and an upper side extending between said front and rear end sides, said upper side being a sealing face and having a lubricant channel being a cutout formed in the sealing strip; a front wall formed at a level of said lubricant channel between said front end side and said lubricant channel; a rear wall forming said sealing face and having a greater wall thickness than said front wall being formed between said lubricant channel and said rear end side; wherein, during an intended use of the sealing strip, said sealing face is set against an inner side of a roller shell of the suction or blower roller in order to seal the positive or negative pressure zone, and lubricant is introduced into an inlet gap between said sealing face and the inner side of the roller shell by way of said lubricant channel, and wherein, during a rotational movement of the roller shell, the roller shell runs onto the sealing strip at said front end side and runs away from the sealing strip on said rear end side; a first material section of the sealing strip being formed of a first material and providing said rear wall in a region of said sealing face and a second material section of the sealing strip being formed of a second material and providing said front wall at least in sections; and said first and second material sections differing from one another in terms of at least one physical property selected from the group consisting of a modulus of elasticity, an abrasion resistance, a hardness and a brittleness; and said first material and said second material are adapted to one another such that, in a friction pairing with the material of the inner side of the roller shell and in sliding friction, said first material has a greater abrasion resistance than said second material.

2. The sealing strip according to claim 1, wherein said second material has a smaller modulus of elasticity than said first material.

3. The sealing strip according to claim 1, wherein said first material is more brittle and/or harder than said second material.

4. The sealing strip according to claim 1, wherein said first material and said second material are adapted to one another such that, in a friction pairing with a material of the inner side of the roller shell and in sliding friction, said first material has a smaller coefficient of friction than said second material.

5. The sealing strip according to claim 1, wherein said first material comprises a rubber/graphite mixture as an essential constituent part thereof.

6. The sealing strip according to claim 1, wherein said second material comprises a plastic material as an essential constituent part thereof.

7. The sealing strip according to claim 6, wherein said plastic material is polyphenylene ether (PPE).

8. The sealing strip according to claim 1, wherein said first material section forms a main body that provides said rear wall with said sealing face, and said second material section forms a lip that provides said front wall and is mounted to said main body.

9. The sealing strip according to claim 8, wherein said lip is configured such that, in a case of an intended use of the sealing strip, with said sealing face set against the inner side of the roller shell, an upper edge of said lip is set against the inner side of the roller shell.

10. The sealing strip according to claim 8, wherein said lip is configured such that, in a case of an intended use of the sealing strip, with said sealing face set against the inner side of the roller shell, an upper edge of said lip is spaced apart from the inner side of the roller shell by no more than 10 mm.

11. The sealing strip according to claim 8, wherein said lip is configured such that, in a case of an intended use of the sealing strip, with said sealing face set against the inner side of the roller shell, an upper edge of said lip is spaced apart from the inner side of the roller shell by no more than 4 mm.

12. The sealing strip according to claim 8, wherein said lip is connected releasably to the main body by way of a non-positive and/or a positive locking engagement.

13. The sealing strip according to claim 8, which comprises a plurality of reinforcing ribs arranged next to one another in a longitudinal direction of the sealing strip and supporting said lip during a rotational movement of the roller shell.

14. The sealing strip according to claim 8, wherein a transition between said lip and said main body has a planar configuration on said front end side.

15. The sealing strip according to claim 1, wherein said rear wall is inclined from a lowest point of said lubricant channel toward said sealing face, with an inclination being directed in the direction of said rear end side.

16. The sealing strip according to claim 15, wherein said inclination towards said rear end side encloses an angle of between 20 and 70 with a horizontal.

17. The sealing strip according to claim 16, wherein said inclination towards said rear end side encloses an angle of between 30 and 50 with the horizontal.

18. The sealing strip according to claim 1, wherein said lubricant channel extends over a greatest part of a length of said sealing strip.

19. A suction or blower roller for a machine for processes or producing web material, comprising: a sealing device for sealing a positive or negative pressure zone of the suction or blower roller, said sealing device including at least one sealing strip according to claim 1; wherein said sealing strip is installed in the suction or blower roller, as viewed in a plane which is defined by a rotational movement of a roller shell, in a position between 7 o'clock and 12 o'clock, if a rotational movement direction of the roller shell is in the clockwise direction and in a position between 5 o'clock and 12 o'clock, if the rotational movement direction of the roller shell is in the counter-clockwise direction.

20. A sealing strip suitable for a sealing device for sealing a positive or negative pressure zone of a suction or blower roller of a machine for processing and/or producing web material, the sealing strip comprising: a front end side, a rear end side, and an upper side extending between said front and rear end sides, said upper side being a sealing face and having a lubricant channel being a cutout formed in the sealing strip; a front wall formed at a level of said lubricant channel between said front end side and said lubricant channel; a rear wall forming said sealing face and having a greater wall thickness than said front wall being formed between said lubricant channel and said rear end side; wherein, during an intended use of the sealing strip, said sealing face is set against an inner side of a roller shell of the suction or blower roller in order to seal the positive or negative pressure zone, and lubricant is introduced into an inlet gap between said sealing face and the inner side of the roller shell by way of said lubricant channel, and wherein, during a rotational movement of the roller shell, the roller shell runs onto the sealing strip at said front end side and runs away from the sealing strip on said rear end side; a main body of the sealing strip being formed of a first material and providing said rear wall in a region of said sealing face; a lip element mounted to said main body and providing said front wall, at least in sections, said lip element being formed of a second material; and said main body and said lip element differing from one another in terms of at least one physical property selected from the group consisting of a modulus of elasticity, an abrasion resistance, a hardness and a brittleness.

21. The sealing strip according to claim 20, wherein said first material and said second material are adapted to one another such that, in a friction pairing with the material of the inner side of the roller shell and in sliding friction, said first material has a greater abrasion resistance than said second material.

22. The sealing strip according to claim 20, wherein said lip element is a separate element being a flexurally elastic lip attached to said main body.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) In the following text, the invention will be explained further using diagrammatic drawings which are not true to scale and in which:

(2) FIG. 1 shows a first embodiment of a sealing strip according to the invention in a suction roller of a paper, cardboard or tissue machine,

(3) FIG. 2 shows a second embodiment of a sealing strip according to the invention in a suction roller of a paper, cardboard or tissue machine,

(4) FIG. 3 shows a third embodiment of a sealing strip according to the invention in a suction roller of a paper, cardboard or tissue machine,

(5) FIG. 4 shows a fourth embodiment of a sealing strip according to the invention in a suction roller of a paper, cardboard or tissue machine,

(6) FIG. 5 shows a lip of a sealing strip according to the invention in a perspective view, and

(7) FIG. 6 shows a suction roller according to the invention.

DESCRIPTION OF THE INVENTION

(8) The sealing strips of the generic type have a longitudinal direction which, in the case of use as intended of the sealing strips, extends in the machine transverse direction of the roller, into which they are installed. The sealing strips 1, 1a, 1b, 1c which are shown in FIGS. 1-4 are shown in a cross-sectional plane which is defined perpendicularly with respect to the longitudinal direction of the sealing strips 1, 1a, 1b, 1c. In the case of use as intended of the sealing strips of the generic type, furthermore, the rotational movement direction of the roller shell runs in the abovementioned cross-sectional plane.

(9) FIG. 1 shows a sealing strip 1 in the case of use as intended in a sealing device (not shown in further detail) of a suction roller of a machine which processes and/or produces web material.

(10) The sealing strip 1 has a front end side 14 and a rear end side 15, and an upper side 19 which extends between the two end sides 14, 15 and provides a sealing face 2 and a lubricant channel 5 which is formed by way of a cutout from the sealing strip 1. As can be seen from the illustration of FIG. 1, the lubricant channel 5 is arranged between the front end side 14 and the sealing face 2. It can be seen from FIG. 1, furthermore, that a front wall 6 is formed at the level H of the lubricant channel 5 between the front end side 14 and the lubricant channel 5, and a rear wall 7 which provides the sealing face 2 is formed between the lubricant channel 5 and the rear end side 15, the rear wall 7 (as viewed in the circumferential direction of a roller shell 4) having a greater wall thickness than the front wall 6.

(11) In the case of use as intended of the sealing strip 1, in order to seal the positive or negative pressure zone, the sealing face 2 can be set against the inner side 3 of the roller shell 4 which comprises a multiplicity of suction holes L, and is in frictional contact with said inner side 3 of the roller shell 4 during a rotational movement D of the roller shell 4. A lubricant (in the form of water in the present case) can be introduced into the inlet gap 8 between the sealing face 2 and the inner side 3 of the roller shell 4 by means of the lubricant channel 5 which is open toward the inner side 3 of the roller shell 4. Furthermore, during a rotational movement D of the roller shell 4, the roller shell 4 runs onto the sealing strip 1 on the front end side 14 and runs off of said sealing strip 1 again on the rear end side 15. As viewed in the rotational movement direction D of the roller shell, the lubricant channel 5 is arranged in front of the sealing face 2 and the front wall 6 is arranged in front of the rear wall 7.

(12) Furthermore, the sealing strip 1 has a lubricant distribution system which is conducted within the sealing strip 1, with a lubricant feed channel 9 which extends in the longitudinal direction of the sealing strip 1 and a multiplicity of riser lines 10 (of which only one can be seen in the illustration of FIG. 1). The riser lines 10 are connected on one end side to the lubricant channel 5 and on the other end side to the lubricant feed channel 9 and are arranged next to one another in the longitudinal direction of the lubricant channel 5.

(13) The sealing strip 1 which is shown in FIG. 1 is formed by way of a first material section which is made from a first material and forms a main body 11, and a second material section which is made from a second material and forms a flexurally elastic lip 12. Here, the main body 11 provides the rear wall 7 with the sealing face 2. Furthermore, the lip 12 provides the front wall 6. In the present case, the first and the second material differ from one another at least in terms of the physical properties modulus of elasticity, abrasion resistance and coefficient of friction. Specifically, the first material comprises substantially a rubber/graphite mixture and has a graphite proportion of 60% by weight and a rubber proportion of 35% by weight, and further constituent parts. The second material comprises polyphenylene ether (PPE) as a substantial constituent part. The first material has a modulus of elasticity of approximately 14 000 N/mm.sup.2 and the second material has a modulus of elasticity of approximately 2400 N/mm.sup.2. The second material therefore has a smaller modulus of elasticity than the first material.

(14) Furthermore, the first material and the second material are adapted to one another in such a way that, in a friction pairing with the material of the inner side 3 of the roller shell 4 (this is steel in the present case) in the case of sliding friction, the first material has a smaller coefficient of friction (namely 0.125) than the second material (namely 0.2).

(15) As can be seen from the illustration of FIG. 1, the lip 12 is designed in such a way that, in the case of use as intended of the sealing strip 1 in the state in which the sealing face 2 is set against the inner side 3 of the roller shell 4, the upper edge 13 lip 12 is set against the inner side 3 of the roller shell 4 and is in frictional contact with the latter. Furthermore, the lip 12 runs in a curved manner as viewed in the movement direction D of the roller shell 4. This can be produced by the lip 12 already being manufactured in a curved manner or else by the lip, without an inherent curvature, experiencing a force which curves it on account of the friction with the roller shell inner side 3. In the last-mentioned case, the lip is presently manufactured in such a way that, in the state in which the sealing face 2 is not set against the roller shell inner side 3, its upper edge 13 projects at the level above the sealing face 2.

(16) In the present case, the lip can be connected releasably at a connecting point 20 to the main body 11, for example in a non-positive manner in the form of a screw connection. In the exemplary embodiment which is shown in FIG. 1, the main body 11 forms the rear end side 15 of the sealing strip 1, furthermore.

(17) Furthermore, the main body 11 has a front side which has a first section 21, a second section 20 and a third section 22, the first section providing a part of the lubricant channel 5, the second section providing the connecting point 20, at which the lip 12 is connected to the main body 11, and the third section 22 providing a part of the front end side 14 of the sealing strip 1.

(18) Accordingly, in the present case, the front end side 14 of the sealing strip 1 is provided by way of the lip 12 and the third section 22 of the front side of the main body 11. It can be seen, furthermore, that the transition between the lip 12 and the main body 11 on the front end side 14 is of planar configuration, that is to say, for example, does not form a step or a shoulder.

(19) It is to be noted that, in all the sealing strips 1, 1a, 1b, 1c which are shown in FIGS. 1-4, the lubricant channel 5 extends in a manner which is inclined from its bottom toward the sealing face, the inclination enclosing an angle between 20 and 70 with a horizontal. Furthermore, in all the sealing strips 1, 1a, 1b which are shown in FIGS. 1-4 and 5, the lubricant channel 5 extends over the greatest part of the length of the respective sealing strip 1, 1a, 1b, 1c.

(20) In the alternative refinements of the sealing strips according to the invention which are shown in FIGS. 2 to 4, only the differences from the sealing strip 1 which is shown in FIG. 1 are to be addressed.

(21) The sealing strip 1a which is shown in FIG. 2 comprises a plurality of reinforcing ribs 16 which are arranged next to one another in the longitudinal direction of the sealing strip and against which the lip 12a is supported during a rotational movement D of the roller shell 4, by the lip 12 being pressed by way of the reinforcing ribs 16 against the rear wall 7. In the present case, the reinforcing ribs 16 are arranged on the lip 12a.

(22) As can be seen from the illustration of FIG. 2, the lip 12a is designed in such a way that, in the case of use as intended of the sealing strip 1a in the state in which the sealing face 2 is set against the inner side 3 of the roller shell 4, the upper edge 13 lip 12a is spaced apart from the inner side 3 of the roller shell 4, the spacing being from 2-4 mm in the present case. Furthermore, the lip 12 runs in an inclined manner as viewed in the movement direction D of the roller shell 4, the lip 12 already being manufactured in an inclined manner.

(23) Furthermore, it can be seen in the sealing strip 1a which is shown in FIG. 2 that the transition between the lip 12a and the main body 11 on the front end side 14 is formed by way of a shoulder.

(24) The sealing strip 1b which is shown in FIG. 3 differs from that of FIG. 2 merely in that the front end side 14 is provided completely by way of the lip 12b. As a result, a planar front end side 14 is likewise provided.

(25) FIG. 4 shows a further sealing strip 1c according to the invention in a cross-sectional plane which is perpendicular with respect to its longitudinal direction. In contrast to the sealing strips 1, 1a and 1b which are shown in FIGS. 1 to 3, the lip 12c of the sealing strip 1c which is shown in FIG. 4 is configured in such a way that, in the case of use as intended, it extends substantially in the radial direction of the roller shell 4. However, FIG. 4 shows the sealing strip 1c in the non-installed state, that is to say without a roller shell.

(26) Furthermore (this is the same as in the case of the sealing strip 1 which is shown in FIG. 1), the main body 11 has a rear side which provides the rear end side 15 of the sealing strip 1c. Furthermore, the main body 11 has a front side with a first section 21, a second section 20 and a third section 22, the first section 21 providing a part of the lubricant channel 5, the second section 20 providing the connecting point of the main body 11 to the lip 12c, and the third section 22 providing a part of the front end side 14 of the sealing strip 1c. This means that, in the embodiment which is shown in FIG. 4, the front end side 14 of the sealing strip is formed in sections by way of the lip 12c and in sections by way of the main body 11, the transition between the lip 12c and the main body 11 on the front end side 14 being of planar configuration, that is to say without a step or shoulder. Furthermore, the rear end side 15 of the sealing strip 1c is formed merely by way of the main body 11. In the present case, the sealing strip 1c which is shown in FIG. 4 is formed merely from the main body 11 and the lip 12c, that section of the lubricant channel 5 which extends from the channel bottom to the sealing face 2 being formed by way of the first section 21 of the main body 11 and running as an oblique plane in a manner which is inclined at an angle from approximately 40 to 50 with respect to the horizontal.

(27) In the sealing strip 1c which is shown in FIG. 4, furthermore, the lip 12c is connected in a positively locking manner to the main body 11 at the connecting point 20. Here, the connecting point 20 forms a dovetail connection which permits a relative mobility of lip 12c and main body 11 in the longitudinal direction of the sealing strip 1c, that is to say in the machine transverse direction of the roller in the case of use as intended thereof, but substantially or completely prevents relative mobility in other directions than the one mentioned above. This embodiment is appropriate, in particular, when the lip 12c and the main body 11 have a different thermal length expansion from one another in the longitudinal direction of the sealing strip 1c.

(28) FIG. 5 shows the lip 12a or 12b in a perspective view with the plurality of reinforcing ribs 16 which are arranged next to one another in the longitudinal direction of the lip 12a, 12b.

(29) A suction or blower roller for a machine which processes and/or produces web material, in particular a paper, cardboard or tissue machine, having a sealing device for sealing a positive or negative pressure zone of the suction or blower roller, the sealing device comprising at least one sealing strip as claimed in one of claims 1 to 14. FIG. 6 shows a suction roller 18 according to the invention for a machine which processes and/or produces web material, in particular a paper, cardboard or tissue machine, in a cross-sectional plane perpendicularly with respect to the longitudinal direction of the suction roller 18. It is to be noted that the longitudinal direction of the sealing strip 1 or 1a or 1b or 1c and that of the suction roller 18 coincide.

(30) According to the second aspect of the invention, the suction roller 18 has at least one sealing device 17 for sealing a negative pressure zone V of the suction roller 18 with respect to the surroundings U. Here, the sealing device 17 comprises at least one sealing strip 1, 1a, 1b or 1c; two sealing strips according to the invention in the present case. According to the invention, the two sealing strips 1, 1a or 1b are installed in the suction roller 18, as viewed in the cross-sectional plane or in a plane which is defined by the rotational movement D of the roller shell 4, in a position from 7 o'clock to 12 o'clock in the case of a rotation in the clockwise direction and in a position from 5 o'clock to 12 o'clock in the case of a rotation counter to the clockwise direction.

(31) In the embodiment which is shown in FIG. 6, the rotation D of the roller shell takes place in the clockwise direction and the two sealing strips 1, 1a, 1b or 1c are installed into the roller 18 in a 10 o'clock position. The two sealing strips 1, 1a, 1b or 1c are installed into the roller 18 as intended, that is to say, as viewed in the rotational movement direction D of the roller shell 4, the lubricant channel 5 is arranged in front of the sealing face 2 and the front wall 6 is arranged in front of the rear wall 7.