CN101321911A

CN101321911A - Web monitoring

Info

Publication number: CN101321911A
Application number: CNA2006800452695A
Authority: CN
Inventors: 托本·施利考; 罗兰·迈耶
Original assignee: Voith Paper Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2005-12-02
Filing date: 2006-10-23
Publication date: 2008-12-10
Anticipated expiration: 2026-10-23
Also published as: EP1960594B1; DE102005057638A1; CN101321911B; WO2007062926A1; DE502006004341D1; ATE437266T1; EP1960594A1

Abstract

The invention relates to a method and a device for web monitoring in a machine for producing and/or refining a web (1) of paper, cardboard, tissue or other fiber material. The web of fiber (1) is supported by an air-permeable belt (8, 9, 23), is impinged upon with hot air by means of at least one hot-air hood (4, 5, 21, 22), the belt (8, 9, 23) being subjected to suction on the face opposite the web of fiber (1) prior to and/or during and/or after hot air impingement. The aim of the invention is to improve monitoring of the web of fiber (1). For this purpose, suction is carried out via one or more suction devices (2, 3, 16, 17, 20) in a plurality of separate suction zones, the vacuum in at least two suction zones being detected by means of respective vacuum sensors (7) and the values measured by the vacuum sensors (7) being supplied to a control unit.

Description

Web monitoring

Technical field

The present invention relates to be used in the machine of production and/or fine paper, cardboard, fabric or other web of fibers, carrying out the method and apparatus of Web monitoring, wherein, the band supporting that web of fiber can be passed through by air, by at least one warm-air pipe hot-air is impacted on the width of cloth, wherein on the side relative, aspirate described band before hot-air impacts and/or between impact epoch and/or after impacting with web of fiber.

Background technology

In modern paper machine, mainly in the drying group, carry out the identification of tearing to paper web by optical pickocff.

Yet the layout of optical pickocff is owing to the position reason and because the temperature sensitivity of sensor is impossible in having the dry route of hot-air blowing.

In addition, the function of the optical pickocff influence of being polluted easily.

In addition, can not recognize rise and the relevant therewith width of cloth vibration and the risk of tearing or tearing at the edge of web of fiber for this reason.

Summary of the invention

Therefore, the technical problem to be solved in the present invention is to monitor the width of cloth of web of fiber better and more reliably and advance.

According to the present invention, this technical problem is following solution about method: aspirate in a plurality of suction districts that separate by one or more aspirators, wherein, detect negative pressure at least two suction districts by each B/P EGR Back Pressure Transducer EGR at least, and the measured value of B/P EGR Back Pressure Transducer EGR is supplied to control module.

The assessment of two suction districts has been improved significantly the reliability of Web monitoring by negative pressure.If tear or the rise at the edge of the rise of web of fiber or web of fiber, then seldom or the negative pressure in the suction district that only covers by web of fiber insufficiently reducing significantly.For this reason, aspirated air consumingly by band on pumping direction, this causes the decline of negative pressure.

In order to assess the decline of pressure-reduction level reliably, in the pressure-reduction level of common 2000Pa at least, should in the suction district, carry out application with respect to the Web monitoring of environment.

The rise of breadths edge or tear and cause pressure-reduction level decline 1000Pa usually, this can relatively easily and reliably be detected by B/P EGR Back Pressure Transducer EGR.

At this advantageously, on width of cloth traffic direction, one after the other arrange a plurality of suction districts.If negative pressure descends in two negative pressuren zones, then can conclude reliably and be out of order.

This point also is applicable to the monitoring that the edge rises especially, and what therefore have advantage equally is one after the other to arrange a plurality of suction districts across width of cloth traffic direction.

According to the structure of drying unit and aspirator, what have advantage certainly is that at least two suction districts are spaced from each other, and/or at least two suction district direct neighbors.Equally, have advantage to be the suction district form by aspirator only or by a plurality of aspirators.

The structure that depends on aspirator, what have advantage equally can be that at least one B/P EGR Back Pressure Transducer EGR is arranged in the aspirator and/or in the suction channel of aspirator, and/or at least one B/P EGR Back Pressure Transducer EGR is arranged between band and the aspirator.

Recognizing by corresponding B/P EGR Back Pressure Transducer EGR in unique suction district or when the negative pressure at least two suction districts of one after the other arranging on width of cloth traffic direction descends, should remove the activation heat air and blow.

This point has prevented because hot-air to the damage of band, because when tearing, lacks the isolation fibrage between warm-air pipe and band.

When the negative pressure in the suction district of arranging across width of cloth traffic direction that recognizes by corresponding B/P EGR Back Pressure Transducer EGR in one or two outside only descends, should introduce the measure that the edge that is used to reduce web of fiber rises.

At this advantageously, rise, improve the pressure-reduction level in corresponding external suction district, and/or rise by additional tension structure tensioning web of fiber for reducing the edge in order to reduce the edge.

About equipment, aspirate by an aspirator or a plurality of aspirators in a plurality of suction districts that separate according to the present invention, wherein, detect negative pressure at least two suction districts, and B/P EGR Back Pressure Transducer EGR is connected with control module by each B/P EGR Back Pressure Transducer EGR.

At this, with the free side of the hot-air air blow fiber width of cloth.When tearing, lose by the covering of web of fiber to band.Therefore, may with cause thermal damage.

The rise of belt edge may cause tearing or tearing of web of fiber, therefore also tackles it and monitors.

According to the structure of the structure of drying unit and aspirator and about the requirement of Web monitoring, favourable can be one after the other to arrange a plurality of aspirators on width of cloth traffic direction, and/or be adjacent to arrange a plurality of aspirators across width of cloth traffic direction.

Equally, what have advantage can be that each aspirator only forms a suction district or at least one aspirator forms a plurality of suction districts.

As requested, can form at least one aspirator by the suction roller, this suction roller is by band and be positioned at outside web of fiber encirclement.

At this, for reliable in function advantageously, at least one B/P EGR Back Pressure Transducer EGR is disposed in the roller.

If the suction box suction of roller by in non-enclosing region, arranging, then for simplified measurement equipment favourable also can be in suction box, to arrange at least one B/P EGR Back Pressure Transducer EGR.

As requested, also can form at least one aspirator by suction box, thereon along it with the interval pilot tape.

At this, for what quick and reliable negative pressure measurement had advantage be, to major general's B/P EGR Back Pressure Transducer EGR be arranged in suction box and the band between.

Description of drawings

Below, in a plurality of embodiment, at length explain the present invention.In each accompanying drawing:

Fig. 1 shows the schematic cross-sectional by the drying unit that has warm-air pipe; With

Fig. 2 shows the another kind structure of drying unit.

The specific embodiment

In two kinds of situations, web of fiber 1 passes through drying unit by 8,9,23 guiding of being with that air can pass through.At this, for drying by warm-

air pipe

4,5,21,22 with the free lateral blowing of hot-air to web of fiber 1.

In order when web of fiber 1 is torn, to avoid since hot-air to 8,9,23 cause thermal damage, Web monitoring is necessary reliably.

Because at

aspirator

2,3,16,17,20

other pilot tapes

8,9,23, the negative pressure of these

aspirators

2,3,16,17,20 can be used for detecting tears during blow warm air.If lack web of fiber 1, then

aspirator

2,3,16,17,20 suction is too much passes through wrong air with 8,9,23, makes the strong decline that pressure-reduction level occurs, and promptly descending surpasses 1000Pa.

In this case, have only suitably when B/P EGR Back Pressure Transducer EGR has been discerned two aspirators of one after the other placing 2,3,16,17,20, adjust just that hot-air blows and warm-

air pipe

4,5,21,22 is opened from being with 8,9,23 pivots.

This pivot is opened and has been prevented the paper obstruction.

Equally, if the edge of web of fiber 1 has then aspirated wrong air from being with 8,9,23 to rise a little.Rise for detecting,

single aspirator

2,3,16,17,20 has a plurality of suction districts across the adjacent layout of width of cloth traffic direction 13.If negative pressure descends in one or two external suction district, then this rise that relatively means the wrong air of suction reliably and therefore mean the respective edges of web of fiber 1.

Because this causes tearing or tearing, so the negative pressure in corresponding suction district improves for use in the edge that aspirates web of fiber 1 consumingly.

In drying equipment according to Fig. 1, web of fiber 1 with 8,9 mutually two according to the aspirator 2,3 of suction roll form on guiding.

At this, aspirate cylinders from the outside by the suction box 6 of in the circumferential area that does not surround, arranging.

At this, be used to detect the advance B/P EGR Back Pressure Transducer EGR 7 of fault of the width of cloth and be positioned at the suction box 6 of cylinder.

At this, web of fiber 1 is sent on the conveyer belt 10 that air can pass through with 11 by the storage machine unit, and wherein, this transmits by the suction guide pulley 12 that surrounds with conveyer belt 10 and supports.

This conveyer belt 10 is sent to being with on 8 of first aspirator 2 with web of fiber 1 then.

During surrounding aspirator 2,, web of fiber 1 is sent to being with on 9 of next aspirator 3 by after 4 pairs of web of fiber 1 blow warm air of warm-air pipe.At this, during centering on, the free side of web of fiber 1 is by warm-air pipe 5 blow warm air.

Shown in figure 2 in the drying equipment, web of fiber 1 by air can pass through with 23 serpentine ground alternately guiding wherein, web of fiber 1 is pressed to the outer cover surface of the heat of drying 14 by the drying 14 and the guide pulley 15 of heating with 23.

Between two dryings 14, be with 23 guiding web of fibers 1, yet by two processing route guidances, wherein web of fiber 1 for being subjected to hot-air, drying impacts.

First handles during the route by drying 14 guiding web of fibers 1 downwards, makes web of fiber 1 upwards arrive subsequently drying 14 once more and handle route by second.

When the first processing route begins, surround aspirator 16 with 23 slightly with being positioned at outside web of fiber 1, aspirator 16 has the form by the cylinder of external suction box 18 suctions.

Handling between the route, will guide around aspirator 17 with web of fiber 1 with 23 according to the suction roll form.

Handle route end second, be with 23 to surround aspirator 16 once more.

Between aspirator 16,17, pass through guide pulley 19 pilot tapes 23 for supporting.Between aspirator 16,17 and the guide pulley 19 and between the guide pulley 19 self, be with 23 to have distance ground according to the static aspirator 20 of suction box form in aspirator 20 other operations.

This static aspirator 20 and prevented damage with 23 with the distance between 23.

Advance for the monitoring width of cloth, B/P EGR Back Pressure Transducer EGR 7 is positioned at the cylinder and the suction box 18 of aspirator 16,17.

In addition, B/P EGR Back Pressure Transducer EGR 17 is at static aspirator 20 and be with between 23, preferably in the processing route of operation downwards.

Warm-air pipe 21,22 is handled the route inherence by being with outside 23 area surrounded for blow warm air is positioned at.

The monitoring of negative pressure on a plurality of suction districts on the width of cloth traffic direction 13 has realized fast detecting and location that the width of cloth is torn.

In order to monitor the rise of breadths edge reliably, has the extension of maximum 500mm across the suction district that separates of the outside of width of cloth traffic direction 13.

Claims

1. method that is used in the machine of production and/or fine paper, cardboard, fabric or other web of fibers (1), carrying out Web monitoring, wherein, the band (8 that described web of fiber (1) can be passed through by air, 9,23) supporting is impacted on this web of fiber (1) with hot-air, wherein on the side relative, aspirate described band (8 before hot-air impacts and/or between impact epoch and/or after impacting with this web of fiber (1), 9,23)

It is characterized in that: by one or more pumping equipments (2,3,16,17,20) in a plurality of suction districts that separate, aspirate, wherein, detect negative pressure at least two suction districts, and the measured value of described B/P EGR Back Pressure Transducer EGR (7) is supplied to control module by each B/P EGR Back Pressure Transducer EGR (7) at least.

2. method according to claim 1 is characterized in that: one after the other arrange a plurality of suction districts on width of cloth traffic direction (13).

3. method according to claim 1 and 2 is characterized in that: be adjacent to arrange a plurality of suction districts across width of cloth traffic direction (13).

4. according to each described method in the above claim, it is characterized in that: at least two suction districts are spaced from each other.

5. according to each described method in the above claim, it is characterized in that: at least two suction district direct neighbors.

6. according to each described method in the above claim, it is characterized in that: described suction district is by an only aspirator (2,3,16,17,20) formation.

7. according to each described method in the claim 1 to 5, it is characterized in that: described suction district is formed by a plurality of aspirators (2,3,16,17,20).

8. according to each described method in the above claim, it is characterized in that: be arranged at least one B/P EGR Back Pressure Transducer EGR (7) in the described aspirator (2,3,16,17,20) and/or its suction channel in.

9. according to each described method in the above claim, it is characterized in that: at least one B/P EGR Back Pressure Transducer EGR (7) is arranged between described band (8,9,23) and the described aspirator (2,3,16,17,20).

10. according to each described method in the above claim, it is characterized in that: recognize by corresponding B/P EGR Back Pressure Transducer EGR (7) in unique suction district or suction district that at least two are one after the other arranged on tape running direction (13) in negative pressure when descending, releasing activation heat air blows.

11. according to each described method in the above claim, it is characterized in that: when the negative pressure in the suction district of arranging across tape running direction (13) that recognizes by corresponding B/P EGR Back Pressure Transducer EGR (7) in one or two outside only descends, introduce the measure of the edge rise that is used to reduce described web of fiber (1).

12. method according to claim 11 is characterized in that: in corresponding external suction district, improving pressure-reduction level in order to reduce the edge rise.

13., it is characterized in that: rise by the additional described web of fiber of tension structure tensioning (1) in order to reduce the edge according to claim 11 or 12 described methods.

14. equipment that is used in the machine of production and/or fine paper, cardboard, fabric or other web of fibers (1), carrying out Web monitoring, wherein, the band (8 that described web of fiber (1) can be passed through by air, 9,23) supporting, by at least one warm-air pipe (4,5,21,22) impact on this web of fiber (1) with hot-air, wherein on the side relative, aspirate described band (8 before hot-air impacts and/or between impact epoch and/or after impacting with web of fiber (1), 9,23), be used for especially carrying out according to each described method of aforementioned claim

It is characterized in that: by one or more pumping equipments (2,3,16,17,20) in a plurality of suction districts that separate, aspirate, wherein, detect negative pressure at least two suction districts, and described B/P EGR Back Pressure Transducer EGR (7) is connected with control module by each B/P EGR Back Pressure Transducer EGR (7) at least.

15. equipment according to claim 14 is characterized in that: on width of cloth traffic direction (13), one after the other arrange a plurality of aspirators (2,3,16,17,20).

16., it is characterized in that: be adjacent to arrange a plurality of aspirators (2,3,16,17,20) across width of cloth traffic direction (13) according to claim 14 or 15 described equipment.

17. according to claim 15 or 16 described equipment, it is characterized in that: each aspirator (2,3,16,17,20) only forms a suction district.

18. according to each described equipment in the claim 14 to 16, it is characterized in that: at least one aspirator (2,3,16,17,20) forms a plurality of suction districts.

19. according to each described equipment in the claim 14 to 18, it is characterized in that: at least one aspirator (2,3,16,17) is formed by the suction cylinder.

20. equipment according to claim 19 is characterized in that: at least one B/P EGR Back Pressure Transducer EGR (7) is disposed in the described cylinder.

21. according to claim 19 or 20 described equipment, it is characterized in that: described cylinder is sucked by the suction box (6,18) of arranging in non-enclosing region, and preferably arranges at least one B/P EGR Back Pressure Transducer EGR (7) in suction box (6,18).

22. according to each described equipment in the claim 14 to 21, it is characterized in that: at least one aspirator (20) is formed by suction box, described thereon band (23) guides with the interval along it.

23. equipment according to claim 22 is characterized in that: at least one B/P EGR Back Pressure Transducer EGR (7) is disposed between described suction box and the described band (23).

24. one kind according to the application in the suction district under the pressure-reduction level of 2000Pa at least of each described Web monitoring in the aforementioned claim.