CN-122029322-A - Sealing strip wear monitoring system and assembly thereof

Abstract

A sealing strip for a suction roll of a paper machine having a wear monitoring system includes a sealing strip having an upper surface, and a wear monitoring system. The wear monitoring system includes a sensor including a first conductive layer, a second conductive layer, and a resistive layer, the first conductive layer and the second conductive layer being mounted on the resistive layer, the second conductive layer being separate from the first conductive layer. The wear monitoring system further includes a signal processor electrically connected to the first conductive layer and the second conductive layer and configured to process a signal related to a resistance between the first conductive layer and the second conductive layer. The sensor is at least partially embedded in the sealing strip.

Inventors

• W. C. Van Pelt

Assignees

• 安德里茨公司

Dates

Publication Date

20260512

Application Date

20240828

Priority Date

20230922

Claims (20)

1. 1. A sealing strip for a suction roll of a paper machine having a wear monitoring system, comprising: A sealing strip having an upper surface, and A wear monitoring system, comprising: A sensor comprising a first conductive layer, a second conductive layer and a resistive layer, the first conductive layer and the second conductive layer being mounted on the resistive layer, the second conductive layer being separate from the first conductive layer, and A signal processor electrically connected to the first and second conductive layers and configured to process a signal related to a resistance between the first and second conductive layers; Wherein the sensor is at least partially embedded in the sealing strip.
2. 2. The seal and wear monitoring system of claim 1 wherein the resistive layer has opposing first and second surfaces, and wherein the first and second conductive layers are mounted to the first surface.
3. 3. The seal and wear monitoring system of claim 1 wherein the resistive layer has opposing first and second surfaces, and wherein the first conductive layer is mounted to the first surface and the second conductive layer is mounted to the second surface.
4. 4. The seal and wear monitoring system of claim 1 wherein the first conductive layer has a free end adjacent an upper surface of the seal, the free end defining an edge of the first conductive layer, the edge being substantially parallel to the upper surface.
5. 5. The seal and wear monitoring system of claim 4 wherein the first conductive layer defines a generally triangular footprint on the resistive layer, wherein an edge of the first conductive layer defines one side of the triangular footprint.
6. 6. The seal and wear monitoring system of claim 5 wherein the second conductive layer defines a generally triangular footprint on the resistive layer.
7. 7. The seal and wear monitoring system of claim 4 wherein the width of the first conductive layer narrows as the first conductive layer extends away from the upper surface from the edge.
8. 8. The seal and wear monitoring system of claim 7 wherein the width of the second conductive layer narrows as the second conductive layer extends away from the upper surface.
9. 9. The seal and wear monitoring system of any one of the preceding claims, wherein the first conductive layer comprises a metal foil.
10. 10. The seal and wear monitoring system of any one of the preceding claims, wherein the resistive layer comprises a carbon film.
11. 11. The weatherstrip and wear monitoring system of any of the preceding claims, wherein the sensor is rolled up into a rolled configuration.
12. 12. A sealing strip for a suction roll of a paper machine having a wear monitoring system, comprising: A sealing strip having an upper surface, and A wear monitoring system, comprising: A sensor comprising a first conductive layer, a second conductive layer and a resistive layer, the first conductive layer and the second conductive layer being mounted on the resistive layer, the second conductive layer being separate from the first conductive layer, and A signal processor electrically connected to the first and second conductive layers and configured to process a signal related to a resistance between the first and second conductive layers; wherein the first conductive layer has a free end adjacent an upper surface of the seal strip, the free end defining an edge of the first conductive layer that is substantially parallel to the upper surface, and Wherein the sensor is rolled up into a rolled configuration and at least partially embedded within a hole therein in the sealing strip.
13. 13. The seal and wear monitoring system of claim 12 wherein the resistive layer has opposing first and second surfaces, and wherein the first and second conductive layers are mounted to the first surface.
14. 14. The seal and wear monitoring system of claim 12 wherein the resistive layer has opposing first and second surfaces, and wherein the first conductive layer is mounted to the first surface and the second conductive layer is mounted to the second surface.
15. 15. The seal and wear monitoring system of claim 12 wherein the width of the first conductive layer narrows as the first conductive layer extends away from the upper surface from the edge.
16. 16. The seal and wear monitoring system of any one of the preceding claims, wherein the first conductive layer comprises a metal foil.
17. 17. A sealing strip for a suction roll of a paper machine having a wear monitoring system, comprising: A sealing strip having an upper surface, and A wear monitoring system, comprising: A sensor comprising a first conductive layer, a second conductive layer and a resistive layer, the first conductive layer and the second conductive layer being mounted on a common surface of the resistive layer, the second conductive layer being separate from the first conductive layer, and A signal processor electrically connected to the first and second conductive layers and configured to process a signal related to a resistance between the first and second conductive layers; wherein the sensor is at least partially embedded in the sealing strip, and Wherein the first conductive layer has a free end adjacent an upper surface of the seal strip, the free end defining an edge of the first conductive layer that is substantially parallel to the upper surface, and Wherein the width of the first conductive layer narrows as the first conductive layer extends away from the upper surface from the edge.
18. 18. The seal and wear monitoring system of claim 17 wherein the first conductive layer comprises a metal foil.
19. 19. The seal and wear monitoring system of claim 17 wherein the width of the first conductive layer narrows as the first conductive layer extends away from the upper surface from the edge.
20. 20. The weatherstrip and wear monitoring system of claim 17, wherein said sensor is rolled up into a rolled configuration.

Description

Sealing strip wear monitoring system and assembly thereof Related applications The present application requests priority and its benefits from U.S. provisional patent application No. 63/584,626, filed on 9/22 of 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical Field The present invention relates generally to papermaking and, more particularly, to suction rolls and apparatus within a papermaking machine. Background Papermaking inherently requires removal of water at many points in the production process. Typically, pulp (slurry of water and wood and other fibers) is carried on top of a felt (in the form of a wide band) that acts as a carrier for the wet pulp before the actual paper is formed. The felt is used to carry pulp in the wet section of the paper machine until sufficient moisture is removed from the pulp to allow the paper to be processed without additional support added by the felt. Quite often, on the wet end of a paper machine, the initial removal of water is accomplished using suction rolls (whether couch, pick-up or press suction rolls) in the press section, which are used in combination with a standard press roll that is imperforate (or in a tissue machine opposite the Yankee dryer), which are matched in registration with the suction rolls. The felt pulp carrier is pressed between the two rolls. The main components of the suction roll 10 include a hollow shell 12 (fig. 1) made of stainless steel, bronze or other metal having tens of thousands of holes drilled radially around the circumference of the roll in a prescribed pattern. The size of these holes is measured (range from less than 1/8 "to nearly 1/4") and is designed for the particular paper material to be treated. It is these holes that form "vents" for removal of water. Such vents may typically comprise about 20% to 45% of the effective roll surface area. The suction roll shell is driven by a drive system which rotates the shell around a stationary core called a suction box. The suction box 20 (fig. 2) can be regarded as a conventional long rectangular box with no cover on top and ports on the ends, bottom or sides. The end of the box, in particular the drive end, is usually provided with a guide bearing, the inner race of which is provided with a guide bush or bearing which is a sliding fit with the journal on the suction box, and the outer race is pressed against the rotating shell. The suction box 20 is connected to a suction source, such as a vacuum pump. An exemplary suction box and shell is shown in U.S. patent No. 6,358,370 to Huttunen, the disclosure of which is incorporated herein in its entirety. To utilize the holes in the shell, these ports must be used on the inside of the suction roll shell in the zone directly below the pulp being treated to create the vacuum zone 30. This is achieved by the suction box 20 using a grooved holder 32, which holder 32 holds the seal on both sides along the long axis of the suction box. Fig. 2 shows a slotted holder 32, and fig. 3 and 4 show two seals 34,34' (hereinafter "sealing strips") in the form of strips. In addition to these long seals, there are two shorter seals (called end seals) on the short ends (called drive and drive ends) that allow some axial adjustment as needed to accommodate various sheet widths. The sealing strips 34,34' are typically made of rubberized polymeric graphite and remain nearly in contact with the inner surface of the shell 12 during operation (see fig. 3 and 4). A constant vacuum is drawn between the sealing strips 34, 34'. This allows creation of a vacuum zone 30 under the sheet 40 as the sheet 40 passes through the roll 10. The sealing strips 34,34 'are biased upwardly toward the suction roll housing 12 by loading tubes 42, which are sealing hoses that extend under the entire length of the sealing strips 34, 34'. The pressure in the loading tube 42 expands the loading tube 42 (much like air in a balloon) and lifts the sealing strips 34,34' toward the inside surface of the shell 12. This effect, together with the aid of the system vacuum from the suction box 20 and the aforementioned laminar flow of lubricating water, forms a seal between the edge of the sealing strip 34 and the inside of the shell 12. In practice, in a normally operating suction roll, the sealing strips 34,34' never directly contact the inside of the suction roll shell 12. If the sealing strips 34,34' contact the housing 12 they will wear away and lose their sealing ability rapidly. To eliminate or significantly reduce such wear and provide a seal, water is applied along the length of the seal strips 34,34' with a lubricating spray formed by the water flowing through the spray nozzles 24 (see FIG. 2). This spray maintains the seal strips 34,34' lubricated by laminar flow of water between the sealing surface and the inside surface of the shell 12. The amount of water used for lubrication should be properly metered so that an appropriate amount of lub