Sealing strip systems for suction rolls

Abstract

Sealing strip holder for suction rolls used for dewatering of sheeting e.g. for paper machines comprises a roll shell with openings and disposed within at least one suction box and methods of using the same.

Claims

1. A method for operating a sealing system of a suction roll, the method comprising: arranging at least one suction box inside a roll shell of the suction roll; and arranging two sealing strip systems which seal a suction zone against the inner side of the roll shell of the suction roll, each sealing strip system comprising: a sealing strip mounting; a sealing strip, which is inserted in the sealing strip mounting, wherein at least one device for inserting lubricant is assigned to at least one of said sealing strips, wherein a temperature in or on one or each of said sealing strips is detected and the amount of inserted lubricant is regulated or controlled based on the temperature of the respective sealing strip.

2. The method according to claim 1, further comprising detecting negative pressure inside the suction box as actual pressure and regulating or controlling advancing pressure of the sealing strips or a distance of the sealing strips to the inner side of said roll shell based on the actual pressure.

3. The method according to claim 2, wherein the advancing pressure of the sealing strips is regulated to the minimum value required for maintaining or setting a predetermined or predeterminable negative pressure in the suction box.

4. The method according to claim 2, wherein the distance of the sealing strips to the inner side of said roll shell is regulated to the value required for maintaining or setting a predetermined or predeterminable negative pressure in the suction box.

5. The method according to claim 1, further comprising detecting and/or monitoring abrasion of the sealing strips during operation.

6. The method according to claim 5, further comprising regulating or controlling the ratio of the advancing pressure of both sealing strips or the distance of the sealing strips to the inner side of said shell on basis of the abrasion of the sealing strips.

7. The method according to the claim 1, further comprising rotating the roll shell around its axis, wherein the roll shell travels from a first sealing strip system towards a second rear sealing strip system, wherein viewed from the direction of travel of the roll shell, the noise level after or on the second rear sealing strip system is detected and the opening angle of the gap between the rear area of the sealing strip of the rear sealing strip system and the inner side of said shell is regulated or controlled on the basis of the detected noise level.

8. The method according to claim 7, wherein the opening angle of the gap between the rear area of the sealing strip of the rear sealing strip system and the inner side of said shell are set as adjustment variable to the value at which the minimal noise level sets in.

9. The method according to claim 1, further comprising transmitting the measured values of the sensors to a mini-server and the mini-server calculates adjustment signals for the regulation of the sealing systems.

10. A sealing system for a suction roll having a roll shell, the sealing system comprising: at least one suction box inside the roll shell of the suction roll; two sealing strip systems which seal the suction box on two opposite sides of the suction box against the roll shell of the suction roll, each sealing strip system comprising: a sealing strip, wherein in at least one sealing strip are at least two temperature sensors integrated or inserted, wherein at least one temperature sensor comprises a larger distance to the surface of the sealing strip, facing the inner wall of the roll shell, than the other temperature sensor or temperature sensors.

11. The sealing strip system according to claim 10, wherein a sealing strip has at least one sensor unit integrated or inserted, wherein the sensor unit comprises a circuit board with at least two temperature sensors, wherein the temperature sensors of the sensor unit are spaced a different distance to the surface of the sealing strip facing the roll shell.

12. The sealing strip system according to claim 11, wherein each sensor unit comprises a power supply and a microchip with a radio module.

13. The sealing strip system according to claim 10, wherein each sealing strip is inserted into a sealing strip mounting, wherein in at least one sealing strip mounting is integrated at least one spray tube, wherein the sealing strip mounting has openings that run from the spray tube to the outside of the sealing strip mounting which, viewed from the direction of travel of the roll shell, is located in front of the sealing strip.

14. The sealing strip system according to claim 13, wherein a sound sensor is integrated into the sealing strip mounting or mounted onto it.

15. The sealing strip system according to claim 10, wherein each sealing strip is inserted into a sealing strip mounting, whereas at least one sealing strip mounting comprises an adjustment element via which the distance of the sealing strip to the roll shell is adjustable, whereas the adjusting element is adjustable in its position via a motor and said motor can hold the adjusting element in a desired position.

16. The sealing strip system according to claim 15, wherein the adjustment element comprises an element displaceable in longitudinal direction of the sealing strip comprising at least one inclined surface, whereas the sealing strip or a height adjustable element connected to the sealing strip is led along this inclined surface.

17. The sealing strip system according to claim 15, wherein the adjustment element acts upon the rear area of the sealing strip, thus facilitating the setting of different values for the distance of the rear distance to the sealing strip to the roll shell from the front area of the sealing strip.

18. The sealing strip system according to claim 17, wherein the advancing pressure of the front end of the sealing strip is adjustable with an advancing tube.

19. The sealing strip system according to claim 17, wherein the front area of the sealing strip also comprises an adjustment element via which the distance of the front area of the sealing strip to the roll shell is adjustable, whereas the adjustment element is adjustable in its position via a motor and said motor can hold the adjusting element in a desired position.

20. The sealing strip according to claim 15, wherein a spring element is mounted in between the sealing strip and the adjustment element.

Description

BRIEF DESCRIPTION OF THE SEVERAL DRAWINGS OF THE INVENTION

(1) The invention provides for drawings for illustration purposes:

(2) FIG. 1: Shows the design of an inventive sealing strip with inventive temperature sensors with abrasion detection.

(3) FIG. 2: Shows schematically an example of an inventive sealing strip system.

(4) FIG. 3: Shows schematically an example of an inventive sealing strip system in a noise reducing embodiment.

(5) FIG. 4: Shows schematically a particularly preferred inventive sealing apparatus of a suction roll.

DETAILED DESCRIPTION OF THE INVENTION

(6) FIG. 1 shows the inventive sealing strip 1.1, 2.1 with integrated temperature sensors 6.1. In this preferred embodiment, several sensor units 6 are integrated into the sealing strip 1.1, 2.1, whereas each sensor unit 6 comprises four temperature sensors 6.1. Regarding the upper surface i.e. the grate and/or friction surface of the sealing strip 1.1, 2.1, the temperature sensors 6.1 comprise different distances. The distance between two consecutively mounted temperature sensors 6.1 is for example 2 mm. The sensor units consist of a circuit board 6.4, temperature sensors 6.1, and a microchip 6.2 with integrated radio module and a power supply via battery 6.3. The setting of the sealing strip 1.1, 2.1 next to the rotating roll shell 3 results in friction and thus in a rise in temperature on the sealing strip 1.1, 2.1. This rise in temperature leads to a change in resistance on the temperature sensors 6.1 positioned on the circuit board 6.4, whereas the temperature is determined via the voltage change caused by the programmed microchip 6.2. If a temperature sensor 6.1 is cut, i.e. destroyed, it results in a disruption of the signal. Thus the microchip 6.2 is able to calculate the exact sealing strip abrasion via the signal disruption in the individual temperature sensors 6.1.

(7) On the outside of the suction roll a mini-server with radio module is positioned which receives data from the sensor units 6 via radio. The mini-server is preferably connected to a network and the data can be visualized via an output device such as a computer, tablet, laptop or mobile phone.

(8) The sealing strip 1.1, 2.1 comprises of one sensor unit 6, preferably the sealing strip 1.1, 2.1 comprises several sensor units 6, in order to facilitate measurement of the temperature in several locations on the sealing strip 1.1, 2.1.

(9) FIG. 2 shows an inventive sealing strip system 1, viewed in direction of travel of the roll shell 3, which is used preferably as the first sealing strip system 1 of a suction box 4, as shown in FIG. 4. The sealing strip system 1 consists of a sealing strip 1.1, which is movably accommodated into the groove of the sealing strip mounting 1.2. An advancing tube 1.3, designed as a pressure tube is set into the groove below the sealing strip 1.1. In front of the sealing strip 1.1 is a sealing strip mounting 1.2 with a lubricant water system comprising spray nozzles 1.4 above which the lubricant water is inserted via a preferred spray tube integrated into the sealing strip mounting 1.2. Preferably at least one sensor unit 6 is integrated and/or inserted into the sealing strip 1.1. The advancing pressure, with which the sealing strip 1.1 is pressed against the inner wall of the roll shell 3, can be adjusted via the pressure in the advancing tube 1.3.

(10) FIG. 3 shows an inventive sealing strip system 2, viewed preferably in direction of travel of the suction roll, which is used as second sealing strip system 2 of a suction box 4, as shown in FIG. 4. The sealing strip system 2 consists of a sealing strip 2.1, which comprises a stop ridge along the lower front edge and which is accommodated movably in the groove of the sealing strip mounting 2.2. The groove contains an advancing tube 2.3 under the stop ridge of the sealing strip 2.1. The sealing strip mounting 2.2 comprises in front of the sealing strip 2.1 of a lubricant water system with spray nozzles 2.4 through which the lubricant water is inserted via a spray tube 2.5, integrated preferably into the sealing strip mounting 2.2. Preferably at least one sensor unit 6 is integrated and/or inserted into the sealing strip 2.1. The advancing pressure with which the sealing strip 2.1 is pressed in the front area against the inner wall of the roll shell 3 can be adjusted via the pressure in the advancing tube 2.3. The sealing strip 2.1 comprises a curved upper surface, thus the upper surface in the front area rests against the roll shell 3 and a gradually increasing gab is formed with the roll shell 3 in the rear area. The width of this gap can be adjusted with a height adjustable strip 2.7, which can shift the rear end of the sealing strip 2.1 closer to the roll shell 3 or away from it.

(11) The height adjustable strip 2.7 is led along a stop ridge that leads upwards at an angle of a sliding strip 2.6 in longitudinal direction of the sealing strip 2.1. The sliding strip 2.6 can be designed as a sliding carriage that is slid into the groove of the sealing strip mounting 2.2 via a motor powered adjusting spindle. A longitudinal displacement of the sliding strip 2.6 results in an upwards displacement of the height adjustable strip 2.7 along the groove. It is also possible to fixedly carry out the strip 2.6 and adjust its height along the groove by longitudinal displacement of the height adjustable strip 2.7. There are several possibilities to convert the rotation movement of the stepper motor into a linear movement of an actuating element, it should be noted that the distance of the rear end of the sealing strip 2.1 to the roll shell 3 is adjustable via a motor and can be held in the respective position.

(12) The sealing strip mounting 2.2 contains preferably a symbolically illustrated sound sensor 7 and/or a pick-up which is used for measuring the noise level on and/or behind the sealing strip 2.1. The inventive regulation method proposes the regulation of the opening angle of the gap between the sealing strip 2.1 and roll shell 3 in such a way that the noise level is reduced to a minimum.

(13) In general, it should be noted with reference to FIG. 4 that instead of pressure tubes 1.3, 2.3 other adjusting devices known to the state of the art can be used on the sealing strip 1.1 and the front end of the sealing strip 2.1. Thus, in addition to the pressure tubes it can comprise clamp devices for fixate the sealing strip in its position temporarily or after achieving a stable, optimal operation mode. Additionally, as known from EP0943729 B1, an additional pressure tube can exist which acts upon the sealing strip in opposite direction of the first pressure tube (advancing tube) in order to be able to pull it away from the roll shell.

(14) According to the invention it is also possible to provide an adjustment mechanism, such as used in the rear area of the sealing strip 2.1, for adjusting the sealing strip 1.1 and the front area of the sealing strip 2.1. The use of an advancing tube is hereby not mandatory. Since, contrary to the rear end of the sealing strip 2.1, its front area and the sealing strip 1.1 can be brought into contact with the roll shell 3, it is necessary to design the advancing pressure in a controllable or regulatable way. The advancing pressure can thus be regulated via a regulable holding torque of the motor or indirectly via a spring element which is located between the adjusting element and the sealing strip. If the sealing strip is already in contact with the roll shell, a force that is gradually increasing with increasing deformation of the spring element and with which the sealing strip is pressed against the roll shell can be applied via a further adjustment of the actuating element. It is advantageous that the actuating element is positioned in such a way that a small gap forms between sealing strip and roll shell.

(15) FIG. 4 shows schematically the design of the suction box 4 with two inventive sealing strip systems 1, 2. The direction of travel of the roll shell 3 is indicated by an arrow. Viewed in direction of travel, the first front sealing strip system 1 is embodied according to FIG. 2, viewed from the direction of travel the second rear sealing strip system 2 is designed according to FIG. 3. FIG. 4 shows how both sealing strip systems 1, 2 form the lateral delimitation of the suction box 4. Thus inside the suction box 4 forms an area 4.1 which is sealed from the remaining interior of the suction roll.

(16) As symbolically shown, the inside of the suction box 4 comprises a pressure sensor 5 for measuring the negative pressure and/or vacuum in the sealed area 4.1. Alternatively, the determination of the negative pressure in the suction box 4 can also occur in or through the vacuum pump which is used to create the vacuum in the sealed area 4.1. The first sealing strip system 1 comprises a temperature sensor system 26 for determining the temperature in the sealing strip 2.1, which preferably consists in the embodiment of several sensor units 6 that are integrated into the sealing strip 2.1 according to FIG. 1. The second sealing strip system 2 comprises further a sensor for noise detection, which preferably consists in the embodiment of a sound sensor 7 integrated into the sealing strip mounting 2.2.

(17) The first sealing strip system 1 comprises an adjusting mechanism to change position of the sealing strip 1.1, which preferably contains an advancing tube 1.3. The advancing pressure of the sealing strip 1.1 and/or the distance between sealing strip 1.1 and roll shell 3 is controllable and/or regulable via the adjustment mechanism. The first sealing strip system 1 comprises a lubricant water supply, whereas the amount of inserted lubricant water is controllable and regulable. The lubricant water supply consists preferably of an embodiment of a spray tube 1.5 integrated sealing strip mounting 1.2. The second sealing strip system 2 comprises an adjustment mechanism to change position of the front area of the sealing strip 2.1 which preferably contains an advancing tube. The advancing pressure of the front area of the sealing strip 2.1 and/or the distance between the front area of the sealing strip 2.1 and the roll shell 3 is controllable and/or regulable via the adjustment mechanism. The second sealing strip system 2 comprises a second adjustment mechanism for changing the position of the rear area of the sealing strip 2.1, which preferably comprises the stepper motor.

(18) The opening angle between the rear area of the sealing strip 2.1 and the roll shell 3 is controllable and/or regulable via the second adjustment mechanism.

(19) The second sealing strip system 2 comprises a lubricant water supply, whereas the amount of inserted lubricant water is controllable and/or regulable. The lubricant water supply consists preferably of the embodiment of a spray tube 2.5 integrated into the sealing strip mounting 2.2.

(20) The inventive adjustment method consists in a first embodiment in the determination of the negative pressure or vacuum in the suction box 4, whereas the advancing pressure or the distance to the roll shell 3 of the first sealing strip 1.1 and the advancing pressure or the distance to the roll shell 3 of the front area of the second sealing strip 2.1 are regulated in such a way that the minimal advancing pressure or the maximum distance is set, which is permissible in order to maintain the vacuum at the desired level inside the suction box 4. The advancing pressure or the distance can thereby be varied for both sealing strips 1.1, 2.1 together, for example by applying the same pressure to both pressure tubes 1.3, 2.3. A particular advantage of this inventive adjustment method is the minimization of the energy consumption of the roll, due to the fact that the vacuum is maintained with minimal advancing pressure, which results in high energy savings. It is also possible to separately regulate the advancing pressure or optionally the distance by applying determinable further control standards for both sealing strip 1.1, 2.1, for example by pressing the worn out strip with less force than the less worn out strip.

(21) In the first embodiment of the adjustment method it preferably further comprises a temperature sensor system 16, 26 for detecting the sealing strip temperature of each sealing strip 1.1, 2.1. The amount of used lubricant water for sealing strip 1.1 is thereby controlled or regulated based on the measured values by the temperature sensor system 16 and the amount of used lubricant water for sealing strip 2.1 is thereby controlled or regulated based on the measured values by the temperature sensor system 26. The regulation of the lubricant water amount based on the temperature of the sealing strip 1.1, 2.1 can also be applied or is also preferable without the above mentioned regulation of the advancing pressure.

(22) A particular advantage of this inventive control and/or regulation method is the minimization of water needs and thus considerably lower water consumption compared to conventional spray rubes.

(23) In addition to the first embodiment, the second embodiment of the inventive regulation further comprises the measurement of the noise level after or on the second sealing strip system 2 and based on the measured values of the distance of the rear area of the sealing strip 2.1 to the roll shell 3 and with that the regulation of the opening angle of the gap between sealing strip 2.1 and roll shell 3, resulting in a minimal noise level.

(24) This method is also preferably applicable separately from the above described method, due to the noise development on conventional sealing strips, which reaches up to 110 dBA and thus constitutes a possible health hazard. The constant noise optimization reduces this potential risk and further preferably creates the most silent and thus most comfortable work environment possible.

(25) Preferably the opening angle of the gap can also be regulated or controlled in such a way that the frequency of the noise is changed, in particular to lower frequencies. The possible disturbing effect of the noise is generally increased significantly by its tonality, which is to be considered when creating a rating level with an additional tonality added to the measured value, the opening value of the gap can also be preferably regulated or controlled that the frequency of the noise is changed according to the predetermined models or stochastically in order to reduce the tonality.

(26) A paper machine generally comprises a variety of suction rolls and thus the regulation or control of the noise emissions of all suction rolls is preferably to be carried out by a central data processing system, such as in particular a mini-server, in order to prevent that the noise emissions of two or more suction rolls contain a simultaneous maximum in the same frequency range.

(27) The invention provides that all measured values of all sensors are transmitted to a mini-server, preferably wireless, in which the regulation and control standards are stored, which can optionally be amended by a program or a user. Using the measured values, the min-server calculates the required adjustment variables for controlling the actuator. The mini-server is preferably connected to a display and input device, in particular wireless, in order to display the operation parameters and/or permit manual amendments.

(28) A particularly advantage of the present invention is that the intelligent system ensures the most energy efficient and most noiseless operation possible and facilitates a preventative maintenance for controlling all important parameters within a suction roll, which is centrally monitored preferably via a mini-server and can be changed dependent on one another either by the system or by the user. The system is based on components with sensors such as in particular sealing strip, pressure tube, sealing strip mounting and spray tube, which preferably supply constant information about the process that prevents outside insight and/or outside control and provide thus information about the operation mode of the suction roll in singular form.