ROLLER FOR A MACHINE FOR PRODUCING AND/OR PROCESSING A PAPER, CARDBOARD, OR TISSUE WEB, AND METHOD FOR OPERATING THE ROLLER

Abstract

A roll for a machine for producing or processing a fibrous web includes a movable roll shell, a positive or negative pressure zone which is disposed within the roll shell and is rotationally fixed relative to the roll shell, and a sealing device for sealing the positive or negative pressure zone from the surroundings. The sealing device has a sealing strip and a lubricating device with which a lubricant can be introduced between the inner surface of the roll shell and the sealing surface of the sealing strip. The lubricating device includes a plurality of lubricant outlet openings and is connected to a supply line for supplying lubricant through a plurality of inlet segments. The supply line includes an inner section which runs within the roll shell, the inner section having a storage volume of at least 490 cm.sup.3/m. A method for operating a roll is also provided.

Claims

1-16. (canceled)

17. A roll for a machine for producing or processing a fibrous web, the roll comprising: a movable roll shell having an inner surface and a positive or negative pressure zone disposed within said roll shell and fixed against rotation relative to said roll shell; a sealing device for sealing off said positive or negative pressure zone from the surroundings, said sealing device having a sealing strip with a length and a sealing surface and said sealing device having a lubricating device for introducing a lubricant between said inner surface of said roll shell and said sealing surface of said sealing strip, said lubricating device including a plurality of lubricant outlet openings; a supply line for supplying lubricant, said supply line including an inner section extending within said roll shell, said inner section having a storage volume of at least 490 cm.sup.3/m based on said length of said sealing strip; and a plurality of inlet segments connecting said lubricating device to said supply line.

18. The roll according to claim 17, wherein said storage volume is at least 2000 cm.sup.3/m.

19. The roll according to claim 17, wherein said inner section includes or is formed of a pipe-shaped part extending substantially entirely over said length of said sealing strip, said pipe-shaped part having an inside diameter of 25 mm or more at least at one location.

20. The roll according to claim 19, wherein said inside diameter of said pipe-shaped part is more than 40 mm.

21. The roll according to claim 19, wherein said inside diameter of said pipe-shaped part is 50 mm or more.

22. The roll according to claim 19, wherein said pipe-shaped part has a length and a constant cross section over more than 50% of its length or over its entire length.

23. The roll according to claim 19, wherein said pipe-shaped part has a length and tapers continuously over its length.

24. The roll according to claim 17, wherein said plurality of lubricant outlet openings are distributed uniformly over said length of said sealing strip or said plurality of lubricant outlet openings include adjacent lubricant outlet openings separated by spacings differing by less than 25% from each other.

25. The roll according to claim 17, wherein said lubricating device is provided wholly or partly in or on said sealing strip, or said lubricant outlet openings are formed in said sealing strip.

26. The roll according to claim 17, wherein said inner section is at least partly rigid.

27. The roll according to claim 17, wherein said sealing device includes a holder for holding said sealing strip, and said inner section extends at least partly on or in said holder.

28. The roll according to claim 17, wherein all of said inlet segments have a length being identical to each other or differing by less than 25% from each other.

29. The roll according to claim 17, wherein said inlet segments have a length of between 150 mm and 700 mm.

30. The roll according to claim 17, wherein said inlet segments have a length of between 200 mm and 400 mm.

31. The roll according to claim 17, wherein said supply line has an outer section extending substantially outside the roll, said outer section having an inside diameter of 25.4 mm or less, and said outer section having an end face guided into an interior of the roll and connected to said inner section.

32. The roll according to claim 31, wherein said inside diameter of said outer section is 12.7 mm or less.

33. The roll according to claim 17, wherein said inlet segments include adjacent inlet segments separated from each other in a longitudinal direction of the roll by spacings being equal to one another or differing from one another by less than 15%.

34. The roll according to claim 33, wherein said spacings differ from one another by less than 5%.

35. The roll according to claim 17, wherein said inlet segments are separated from each other in a longitudinal direction of the roll by spacings of less than 2 m.

36. The roll according to claim 35, wherein said spacings between said inlet segments are less than 1.75 m.

37. The roll according to claim 35, wherein said spacings between said inlet segments are 1.5 m or less.

38. A method for operating a roll for a machine for producing or processing a fibrous web, the method comprising: providing a roll according to claim 17; and supplying said lubricating device with less than 2.4 l/min/m of lubricant.

39. The method according to claim 38, which further comprises supplying said lubricating device with between 0.4 l/min/m and 1.5 l/min/m of lubricant.

40. The method according to claim 38, which further comprises: supplying the lubricating device with a first quantity of lubricant over a starting time period; and supplying the lubricating device with a second quantity of lubricant after the starting time period; the first quantity of lubricant being greater than the second quantity of lubricant.

41. The method according to claim 40, wherein the first quantity of lubricant is more than 25% greater than the second quantity of lubricant.

42. The method according to claim 38, wherein the starting time period is at least 30 seconds.

43. The method according to claim 38, wherein the starting time period is between 30 seconds and 5 min.

Description

[0037] The invention will be explained in more detail below by using schematic drawings, the invention not being restricted to these embodiments.

[0038] FIG. 1 shows a detail of a roll according to one aspect of the invention

[0039] FIG. 2 shows a detail of the roll according to a further aspect of the invention

[0040] FIG. 3 shows a detail of a roll according to a further aspect of the invention

[0041] FIG. 4 shows a detail of a roll according to a further aspect of the invention.

[0042] FIG. 1 shows a roll 1 having a roll shell 11 and an end face 12. Such a roll can be, for example, a suction roll 1. A sealing device 2 is provided in the interior of the roll 1. The former comprises a sealing strip 3, which is arranged in a sealing strip holder 3a, and a lubricating device 4. The lubricating device 4 shown in FIG. 1 is largely located in the sealing strip 3. A multiplicity of lubricant outlet openings 5 are arranged beside one another. These openings 5 are placed such that the emerging lubricant gets between the sealing surface of the sealing strip 3 and the roll shell 11. For the supply of the lubricating device 4 with lubricant, e.g. with lubricating water, a supply line 6 is provided, which comprises an inner section 7 which extends in the interior of the roll shell 11, and has a storage volume of at least 490 cm.sup.3/m, in particular at least 500 cm.sup.3/m, preferably of at least 2000 cm.sup.3/m, based on the length of the sealing strip, and an outer section 8. Via a plurality of inlet segments 9, 9a, the lubricating device 4 is connected to the inner section 7 of the supply line 6 at a plurality of inlets 10, 10a. In advantageous embodiments, the spacings of two adjacent inlet segments 9, 9a and/or two adjacent inlets 10, 10a can each be equal. Alternatively or additionally, provision can also be made for the inlet segments 9, 9a to be arranged such that their spacing from one another in the longitudinal direction of the roll 1 is less than 2 m, in particular less than 1.75 m, preferably 1.5 m or less. The spacing of an inlet segment 9a or an inlet 10a from a longitudinal end of the sealing strip 3 can preferably be at most 800 mm, in particular at most 600 mm, preferably 400 mm or less. Advantageously, the length of the inlet segments can be between 150 mm and 700 mm, in particular between 200 mm and 400 mm. It is a very advantageous embodiment here when the inner section 7 is mounted on the outside of the suction box of a negative pressure zone. Firstly, this mounting position is more easily accessible than in the interior of the suction box. Secondly, the spacing of the inner section 7 of the supply line to the inlets 10, 10a of the sealing strip is usually lower, so that it is possible to manage with shorter inlet segments 9, 9a with a length of, for example, 150 mm-250 mm.

[0043] The inner section 7 of the supply line in FIG. 1 comprises a pipe-shaped part. This pipe advantageously be made of a material (e.g. metal or plastic) which is more rigid than the inlet segments 9, 9a. It is possible, for example, to use pipes having internal diameters of 25 mm (corresponding to a storage volume of about 500 cm.sup.3/m), 40 mm or 50 mm (corresponding to a storage volume of about 2000 cm.sup.3/m). The inlet segments 9, 9a can be embodied, for example, as hose segments.

[0044] FIG. 2 differs from FIG. 1 in that the inner section 7 consists of a pipe 7 which tapers continuously over its length.

[0045] FIG. 3 shows a sealing strip 3 in a holder 3a, which is pressed against the inside of the roll shell 11 of the roll 1 by means of a pressure hose 13. Such a use of a pressure hose for pressing onto a moving surface such as a roll shell is a measure which is usual and known to those skilled in the art. As distinct from the embodiments shown in FIGS. 1 and 2, in FIG. 3 the lubricating device 4 is not integrated into the sealing strip. The lubrication is implemented by means of a number of spray nozzles, which provide the outlet openings 5. The spray nozzles are connected to the inner section 7 of the supply line via inlet segments 9.

[0046] A further advantageous feature which, in FIG. 3, is implemented together with the spray nozzles but which is also possible in combination with a lubricating device 4 integrated into the sealing strip 3, consists in the inner section 7 of the supply line extending at least partly at least partly on or in the sealing strip holder 3a. This inner section 7 provides the storage volume of at least 490 cm.sup.3/m, in particular at least 500 cm.sup.3/m, and can, for example, have the form of a cylinder or a tapering cylinder.

[0047] In FIG. 4, essential components of the invention are illustrated, once more schematically. In a sealing strip 3 with an integrated sealing device, the lubricant outlet openings 5 are supplied with lubricant via inlets 10, 10a. The inlets 10, 10a are connected to the inner section 7 of the supply line via inlet segments 9, 9a. The inner section 7 is again embodied as a pipe, which also provides the storage volume. The spacings of the longitudinal end of the sealing strip 3 from the first inlet 10a and from the first inlet segment 9a are designated by d1 and d5, while the spacings of adjacent inlets 10, 10a and adjacent inlet segments 9, 9a from one another are designated by d2, d3, d4. The number of four inlets here is exemplary. It is entirely possible for more or fewer inlets/inlet segments to be provided.

[0048] The following table indicates some advantageous spacings of the inlet segments and the inlets.

TABLE-US-00001 Example No. d.sub.1 d.sub.2 d.sub.3 d.sub.4 d.sub.5 #1 400 mm 1360 mm 1360 mm 1360 mm 400 mm #2 640 mm 1200 mm 1200 mm 1200 mm 640 mm #3 540 mm 1250 mm 1300 mm 1250 mm 540 mm

[0049] As can be seen in, the “inner” spacings d2−d4 can be equal or differ by a few millimeters. This can be necessitated, for example, by the installation situation.

LIST OF DESIGNATIONS

[0050] 1 Roll [0051] 2 Sealing device [0052] 3 Sealing strip [0053] 3a Holder [0054] 4 Lubricating device [0055] 5 Lubricant outlet openings [0056] 6 Supply line [0057] 7 Inner section [0058] 8 Outer section [0059] 9, 9a Inlet segment [0060] 10, 10a Inlet [0061] 11 Roll shell [0062] 12 End face [0063] 13 Pressure hose