CN220455130U - Paper air permeability detection device - Google Patents
Paper air permeability detection device Download PDFInfo
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- CN220455130U CN220455130U CN202321559251.4U CN202321559251U CN220455130U CN 220455130 U CN220455130 U CN 220455130U CN 202321559251 U CN202321559251 U CN 202321559251U CN 220455130 U CN220455130 U CN 220455130U
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- 230000035699 permeability Effects 0.000 title claims abstract description 43
- 238000001514 detection method Methods 0.000 title claims abstract description 17
- 238000007789 sealing Methods 0.000 claims abstract description 40
- 230000001105 regulatory effect Effects 0.000 claims abstract description 14
- 238000001914 filtration Methods 0.000 claims abstract description 13
- 238000010926 purge Methods 0.000 claims description 50
- 230000003028 elevating effect Effects 0.000 claims description 5
- 238000005259 measurement Methods 0.000 abstract description 25
- 238000007664 blowing Methods 0.000 abstract description 4
- 238000012423 maintenance Methods 0.000 description 11
- 238000000034 method Methods 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000428 dust Substances 0.000 description 2
- 239000000945 filler Substances 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
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Abstract
The utility model discloses a paper air permeability detection device, which comprises an air passage control part, a measuring head and a measuring head lifting device, wherein the air passage control part is provided with a filtering pressure reducing valve, a blowing air passage, a measuring air passage, a sealing air passage and a measuring head control air passage; the measuring gas path is sequentially provided with: the device comprises a measuring gas circuit pressure regulating valve, a proportional valve, a measuring vacuum generator, a flowmeter, a measuring electromagnetic valve, a measuring gas circuit filter, a vacuum pressure electromagnetic valve and a pressure transmitter; the rear end of the measuring gas circuit filter is also connected with a plurality of miniature hand valves which are connected to measuring holes of the measuring head. The measuring hole participating in measurement is controlled by the switch of the miniature hand valve of the measuring gas circuit, namely the measuring area is changed, the linear measuring range of the air permeability can be adjusted under the condition that the measuring range of the flowmeter is unchanged, and the air permeability measuring precision is improved.
Description
Technical Field
The utility model relates to the field of detection devices, in particular to the technical field of online detection of air permeability of paper.
Background
Most of the existing online air permeability detection devices are complete sets, the detection area of one set of products cannot be changed, the air permeability measurement range is small, only one of the paper sheets with high air permeability and low air permeability can be detected, one paper machine production line can possibly produce products with different air permeability from tens of Cu to thousands of Cu or from thousands of Cu to tens of thousands of Cu, and if the online air permeability detection devices with the detection area incapable of being changed are adopted, a plurality of sets of online air permeability detection devices are required to be installed on one paper machine production line.
Disclosure of Invention
In order to solve the problems of the background technology, the utility model provides a paper air permeability detection device, which comprises an air passage control part, a measuring head and a measuring head lifting device, wherein the air passage control part is provided with a filtering pressure reducing valve, a purging air passage, a measuring air passage, a sealing air passage and a measuring head control air passage, the filtering pressure reducing valve is respectively connected with a total air source electromagnetic valve, the purging air passage and the measuring head control air passage, and the total air source electromagnetic valve is respectively connected with the measuring air passage and the sealing air passage;
the measuring gas path is sequentially provided with: the device comprises a measuring gas circuit pressure regulating valve, a proportional valve, a measuring vacuum generator, a flowmeter, a measuring electromagnetic valve, a measuring gas circuit filter, a vacuum pressure electromagnetic valve and a pressure transmitter; the rear end of the measuring gas circuit filter is also connected with a plurality of miniature hand valves, and the miniature hand valves are connected to the measuring holes of the measuring head.
The utility model is further provided with: the miniature hand valves are two or three, are respectively connected with the measuring holes of the measuring head, which are not communicated with each other, and whether the miniature hand valve is connected with the measuring holes or not is determined by the switch of the miniature hand valve.
The utility model is further provided with: the measuring head is divided into a high-transmission measuring head and a low-transmission measuring head, wherein the high-transmission measuring head is provided with two circular measuring holes, one hole area is 0.2 square centimeter, and the other hole area is 0.5 square centimeter; the low-permeability measuring head is provided with three oval measuring holes, the total area is 10.5 square centimeters, the measuring heads are all integrally processed, and the measuring holes are not connected with each other.
The utility model is further provided with: the measuring head control air path is provided with a measuring head lifting control electromagnetic valve and a throttle valve, and the throttle valve is connected to the measuring head lifting device and used for controlling the lifting speed of the measuring head.
The utility model is further provided with: the sealing gas circuit comprises a sealing gas circuit pressure regulating valve and a sealing vacuum generator, and the rear end of the sealing vacuum generator is connected to the sealing ring of the measuring head.
The utility model is further provided with: the purging gas circuit comprises a measuring gas circuit purging electromagnetic valve and a sealing gas circuit purging electromagnetic valve, the rear end of the filtering pressure reducing valve is respectively connected with the measuring gas circuit purging electromagnetic valve and the sealing gas circuit purging electromagnetic valve, and the measuring gas circuit purging electromagnetic valve is connected between the measuring electromagnetic valve and the measuring gas circuit filter; the sealed gas circuit purging electromagnetic valve is connected between the sealed vacuum generator and the measuring head.
The utility model has the following beneficial effects: the utility model adopts the independent detection and control element to access the DCS/PLC, realizes convenient remote control and interlocking control in the DCS/PLC, has simple structure, easy purchase of the element, convenient maintenance and low maintenance cost; the measuring hole participating in measurement is controlled by the switch of the miniature hand valve of the measuring gas circuit, namely the measuring area is changed, the linear measuring range of the air permeability can be adjusted under the condition that the measuring range of the flowmeter is unchanged, and the air permeability measuring precision is improved; the flow change during the switching of the miniature hand valve can also help to quickly diagnose faults, quickly judge leakage points of the air permeability air path and improve maintenance efficiency.
Drawings
Fig. 1 is an overall gas circuit schematic of the present utility model.
Fig. 2 is a low-permeability probe according to an embodiment of the present utility model.
Fig. 3 is a diagram of a second high-permeability probe according to a probe embodiment of the present utility model.
Fig. 4 is a wiring diagram of an electric cabinet according to the present utility model.
1. The device comprises a filtering pressure reducing valve 2, a total air source electromagnetic valve 3, a measuring air passage pressure regulating valve 4, a proportional valve 5, a measuring vacuum generator 6, a flowmeter 7, a measuring electromagnetic valve 8, a measuring air passage filter 9, a vacuum pressure electromagnetic valve 10, a pressure transmitter 11, a sealing vacuum generator 12, a measuring head 13, a measuring head lifting device 14, a measuring air passage purging electromagnetic valve 15, a sealing air passage purging electromagnetic valve 16, a measuring head lifting control electromagnetic valve 17, a throttle valve 18, a miniature hand valve 19 and a sealing air passage pressure regulating valve.
Detailed Description
Preferred embodiments of the present utility model are described below with reference to fig. 1-4. It should be understood by those skilled in the art that these embodiments are merely for explaining the technical principles of the present utility model, and are not intended to limit the scope of the present utility model.
The utility model provides a paper air permeability detection device, which comprises an air passage control part, a measuring head and a measuring head lifting device 13, wherein the air passage control part is provided with a filtering pressure reducing valve 1, a blowing air passage, a measuring air passage, a sealing air passage and a measuring head control air passage, the filtering pressure reducing valve 1 is respectively connected with a total air source electromagnetic valve 2, the blowing air passage and the measuring head control air passage, and the total air source electromagnetic valve 2 is respectively connected with the measuring air passage and the sealing air passage;
the measuring gas path is sequentially provided with: the measuring gas circuit pressure regulating valve 3, the proportional valve 4, the measuring vacuum generator 5, the flowmeter 6, the measuring electromagnetic valve 7, the measuring gas circuit filter 8, the vacuum pressure electromagnetic valve 9 and the pressure transmitter 10; the rear end of the measuring gas circuit filter 8 is also connected with a plurality of miniature hand valves 18, and the miniature hand valves 18 are connected to the measuring holes of the measuring head 12.
The number of the miniature hand valves 18 is two or three, and the miniature hand valves 18 are respectively connected with the measuring holes which are not communicated with each other of the measuring head 12, and whether the miniature hand valves 18 are connected with the measuring holes or not is determined to participate in measurement through the switch of the miniature hand valves 18.
The measuring head is divided into a high-transmission measuring head and a low-transmission measuring head, wherein the high-transmission measuring head is provided with two circular measuring holes, one hole area is 0.2 square centimeter, and the other hole area is 0.5 square centimeter; the low-permeability measuring head is provided with three oval measuring holes, the total area is 10.5 square centimeters, the measuring heads are all integrally processed, and the measuring holes are not connected with each other.
The measuring head control air path is provided with a measuring head lifting control electromagnetic valve 16 and a throttle valve 17, and the throttle valve 17 is connected to the measuring head lifting device 13 and used for controlling the lifting speed of the measuring head.
The sealed gas circuit comprises a sealed gas circuit pressure regulating valve 19 and a sealed vacuum generator 11, and the rear end of the sealed vacuum generator 11 is connected to the sealing ring of the measuring head 12.
The purging gas circuit comprises a measuring gas circuit purging electromagnetic valve 14 and a sealing gas circuit purging electromagnetic valve 15, the rear end of the filtering pressure reducing valve 1 is respectively connected with the measuring gas circuit purging electromagnetic valve 14 and the sealing gas circuit purging electromagnetic valve 15, and the measuring gas circuit purging electromagnetic valve 14 is connected between the measuring electromagnetic valve 7 and the measuring gas circuit filter 8; the sealed gas circuit purge solenoid valve 15 is connected between the sealed vacuum generator 11 and the gauge head 12.
Working principle: the production compressed air is filtered and stabilized by the filtering pressure reducing valve 1 to provide clean working compressed air for the measuring system. The working gas source pressure of the proportional valve 4 is regulated by the measuring gas path pressure regulating valve 3 on the measuring gas path; the proportional valve 4 adjusts the pressure of the outlet compressed air in real time, and finely adjusts the vacuum pressure of the measuring gas circuit to a set value; the flowmeter 6 measures the air flow rate of the fixed area of the measuring hole passing through the measuring head 12 under the set vacuum; the measurement electromagnetic valve 7 is opened during measurement, and is closed during purging and 'local' maintenance states, so that dust is prevented from being reversely blown into the flowmeter during purging, and the measurement accuracy is prevented from being influenced; the measuring gas path filter 8 is used for filtering the air containing dust and filler, which is sucked from the measuring head by constant vacuum generated by the measuring vacuum generator 5; the vacuum pressure electromagnetic valve 9 is opened in the measurement process, and is closed in the purging and 'local' maintenance states as in the measurement electromagnetic valve 7, so that the vacuum pressure transmitter 10 is protected, and the pressure transmitter is prevented from being damaged by the purging positive pressure; the pressure transmitter 10 and the proportional valve 4 form closed-loop control, and the vacuum of the measuring hole is stably controlled at a set vacuum value; the measuring head 12 is provided with a plurality of measuring holes which are not communicated with each other, the measuring holes are connected into a measuring gas path through 2 or 3 miniature hand valves 18, and the total area of the measuring holes is controlled through the switch of the miniature hand valves 18, so that the air flow sucked by measuring vacuum through the measuring holes is in the range of the measuring range of the flowmeter 6; the measurement gas path purging solenoid valve 14 is opened during purging, and the measurement gas path filter 3 and the measurement hole of the measuring head 12 are purged by positive pressure. The sealed gas path purging solenoid valve 15 is opened during purging, and the sealed gas path and the measuring head sealing ring area are purged by positive pressure. The gauge head lifting control electromagnetic valve 16 controls the gauge head lifting device 13 to drop the gauge head when paper is broken or purged, and purging is performed after a few seconds, so that the paper is prevented from being broken by purge compressed air; the throttle valve 17 controls the speed of the elevating operation of the probe elevating device 13 to reduce mechanical vibration. The sealing vacuum pressure regulating valve 19 regulates the working compressed air pressure of the sealing vacuum generator 11, the sealing vacuum of the sealing annular area of the measuring head 12 is controlled in a proper range, the too high sealing vacuum can generate suction groove marks on paper sheets, and the too low vacuum can not form effective measurement seal, so that the air leakage is too large or fluctuates, and the measurement is influenced.
The formula of the air permeability measurement principle is as follows:
according to the air permeability calculation formula, the air flow passing through the paper in unit time and unit area is the air permeability of the paper under the condition of a certain vacuum pressure, and the air flow is in direct proportion to the measurement area, so that the measurement area is changed through the on-off control of 2 or 3 micro hand valves under the condition that the measuring range of the air flowmeter is determined; the micro hand valve is opened to measure the air permeability, and the micro hand valve is closed to measure the air permeability without the air permeability; thus, the measurement range of the air permeability can be enlarged.
The working process comprises the following steps: the on-site setting 'maintenance mode' pulls the switch, pulls to 'local maintenance' position during local maintenance operation, and the total gas source solenoid valve 1 loses power and closes this moment, and measurement gas circuit sweeps solenoid valve 14 and sealed gas circuit and sweeps solenoid valve 15 and lose power and close, and gauge head elevating solenoid valve 16 loses power and closes, and gauge head elevating gear 13 control gauge head falls down, and the system is in the state of stopping detecting.
After the paper is normally drawn when the machine is started, an operator can pull the switch to a 'remote' position on site, so that the online air permeability detection device can be remotely started on the DCS operation station, and the online air permeability detection device can enter an air permeability operation mode under the condition of paper. After the air permeability system operates, the air permeability system firstly enters a purging state, and a measuring air passage purging electromagnetic valve 14 and a sealing air passage purging electromagnetic valve 15 are sequentially switched on and off to purge the measuring air passage and the sealing air passage for one time. After the purging is finished, the system enters a measuring state, a measuring gas path purging electromagnetic valve 14 and a sealing gas path purging electromagnetic valve 15 are closed, a measuring head is controlled to rise through a measuring head lifting device 13, the lifting speed of the measuring head is controlled through a measuring head lifting control electromagnetic valve 16, a throttle valve 17 is controlled to control the lifting speed, a total gas source electromagnetic valve 2, a vacuum pressure electromagnetic valve 9 and a measuring electromagnetic valve 7 are opened, the measuring gas path vacuum pressure detected by a pressure transmitter 10 is regulated through a proportional valve 4, and meanwhile, a flowmeter 6 measures the air flow passing through the measuring head 12; when the deviation between the vacuum pressure measured value and the set value meets the set requirement, calculating the air permeability value through the formula, and displaying the air permeability value on a system interface. The slope and intercept are used at the DCS/PLC to correct for linear deviations of the online air permeability measurements from laboratory values. When the measurement mode is carried out for a set purging interval time, the measuring head automatically falls down to purge, then the measurement mode is entered, and the steps are repeated to carry out continuous measurement. The time between each purging and the length of the purging time can be modified according to the deposition condition of the filler of the measuring head. In any step, clicking a stop button on the DCS/PLC operation computer stops the system.
The utility model adopts the independent detection and control element to access the DCS/PLC, realizes convenient remote control and interlocking control in the DCS/PLC, has simple structure, easy purchase of the element, convenient maintenance and low maintenance cost; the measuring hole participating in measurement is controlled by the switch of the miniature hand valve of the measuring gas circuit, namely the measuring area is changed, the linear measuring range of the air permeability can be adjusted under the condition that the measuring range of the flowmeter is unchanged, and the air permeability measuring precision is improved; the flow change during the switching of the miniature hand valve can help to quickly diagnose faults, quickly judge leakage points of the air passage with air permeability and improve maintenance efficiency;
the sealing vacuum pressure regulating valve is connected to the sealing vacuum generator and generates sealing vacuum in the area of the measuring head sealing ring. The measuring head lifting device automatically controls to automatically fall and purge according to the set purging interval time and paper breakage. And the automatic control program is detected to complete the functions of paper breaking and falling measuring head, periodic lifting and falling measuring head blowing, automatic vacuum measurement control and real-time air permeability calculation.
While the utility model has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the utility model, and in particular, the technical features set forth in the various embodiments may be combined in any manner so long as there is no structural conflict. The present utility model is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.
In the description of the present utility model, terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like, which indicate a direction or a positional relationship, are based on the direction or the positional relationship shown in the drawings, are merely for convenience of description, and do not indicate or imply that the apparatus or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus are not to be construed as limiting the present utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
Furthermore, it should be noted that, in the description of the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those skilled in the art according to the specific circumstances.
The terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, article, or apparatus/means that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, article, or apparatus/means.
Thus far, the technical solution of the present utility model has been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of protection of the present utility model is not limited to these specific embodiments. Equivalent modifications and substitutions for related technical features may be made by those skilled in the art without departing from the principles of the present utility model, and such modifications and substitutions will fall within the scope of the present utility model.
Claims (6)
1. The utility model provides a paper air permeability detection device, includes gas circuit control portion, gauge head and gauge head elevating gear (13), its characterized in that: the gas circuit control part is provided with a filtering pressure-reducing valve (1), a purging gas circuit, a measuring gas circuit, a sealing gas circuit and a measuring head control gas circuit, wherein the filtering pressure-reducing valve (1) is respectively connected with a total gas source electromagnetic valve (2), the purging gas circuit and the measuring head control gas circuit, and the total gas source electromagnetic valve (2) is respectively connected with the measuring gas circuit and the sealing gas circuit;
the measuring gas path is sequentially provided with: a measuring gas circuit pressure regulating valve (3), a proportional valve (4), a measuring vacuum generator (5), a flowmeter (6), a measuring electromagnetic valve (7), a measuring gas circuit filter (8), a vacuum pressure electromagnetic valve (9) and a pressure transmitter (10); the rear end of the measuring gas circuit filter (8) is also connected with a plurality of miniature hand valves (18), and the miniature hand valves (18) are connected to the measuring holes of the measuring head (12).
2. The paper air permeability detecting apparatus according to claim 1, wherein: the number of the miniature hand valves (18) is two or three, and the miniature hand valves are respectively connected with the non-communicated measuring holes of the measuring head (12).
3. The paper air permeability detecting apparatus according to claim 1, wherein: the measuring head is divided into a high-transmission measuring head and a low-transmission measuring head, wherein the high-transmission measuring head is provided with two circular measuring holes, one hole area is 0.2 square centimeter, and the other hole area is 0.5 square centimeter; the low-permeability measuring head is provided with three oval measuring holes, the total area is 10.5 square centimeters, the measuring heads are all integrally processed, and the measuring holes are not connected with each other.
4. The paper air permeability detecting apparatus according to claim 1, wherein: the measuring head control air path is provided with a measuring head lifting control electromagnetic valve (16) and a throttle valve (17), and the throttle valve (17) is connected to the measuring head lifting device (13).
5. The paper air permeability detecting apparatus according to claim 1, wherein: the sealing gas circuit comprises a sealing gas circuit pressure regulating valve (19) and a sealing vacuum generator (11), and the rear end of the sealing vacuum generator (11) is connected to the sealing ring of the measuring head (12).
6. The paper air permeability detecting apparatus according to claim 5, wherein: the purging air circuit comprises a measuring air circuit purging electromagnetic valve (14) and a sealing air circuit purging electromagnetic valve (15), the rear end of the filtering pressure reducing valve (1) is respectively connected with the measuring air circuit purging electromagnetic valve (14) and the sealing air circuit purging electromagnetic valve (15), and the measuring air circuit purging electromagnetic valve (14) is connected between the measuring electromagnetic valve (7) and the measuring air circuit filter (8); the sealed gas path purging electromagnetic valve (15) is connected between the sealed vacuum generator (11) and the measuring head (12).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN202321559251.4U CN220455130U (en) | 2023-06-19 | 2023-06-19 | Paper air permeability detection device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202321559251.4U CN220455130U (en) | 2023-06-19 | 2023-06-19 | Paper air permeability detection device |
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CN220455130U true CN220455130U (en) | 2024-02-06 |
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CN202321559251.4U Active CN220455130U (en) | 2023-06-19 | 2023-06-19 | Paper air permeability detection device |
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CN (1) | CN220455130U (en) |
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2023
- 2023-06-19 CN CN202321559251.4U patent/CN220455130U/en active Active
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