Deformation monitoring system and method for lower header structure of water cooling wall of boiler

Abstract

The invention belongs to the technical field of header state monitoring, and particularly relates to a boiler water-cooled wall lower header structure deformation monitoring system and method. Comprising an expansion acquisition module, a strain acquisition module and a temperature acquisition module, the expansion acquisition module is connected with an expansion processing module, the strain acquisition module is connected with a strain processing module, and the temperature acquisition module is connected with a temperature processing module. The expansion processing module, the strain processing module and the temperature processing module are all connected with an optical fiber switch, the optical fiber switch is connected with a server, an SIS system, a container stress calculation system and a storage system are arranged in the server, the SIS system comprises an early warning program, and the server is connected with a client. Stress and expansion information and temperature information of the lower header can be obtained in real time for a long time, the stress state of the header is obtained in real time, the health state of the header is intelligently judged, and an alarm is automatically given according to abnormal problems.

Description

Technical Field

[0001] The present invention belongs to the technical field of header status monitoring, and in particular relates to a system and method for monitoring the deformation of a boiler water wall lower header structure. Background Art

[0002] Leakage in power plant boilers is a major risk to the safe and stable operation of units. According to statistics from a large power generation group, approximately 70% of boiler-side accidents are caused by "four-pipe leaks." These leaks account for approximately 40% of unplanned downtime and over 50% of all power generation losses due to accidents. Leakage accidents frequently occur in the water-wall, superheater, reheater, and economizer sections. For example, a 1910t / h Bunsen-type once-through boiler at a power plant repeatedly experienced leaks from transverse cracks in the water-wall between 2005 and 2007, with the leaks concentrated in the front and rear water-wall sections.

[0003] As a key component connecting the various heating surface tubes, the safety of the header is of paramount importance. Any problems with the header, such as deformation or damage due to thermal stress, will directly affect the water circulation and steam distribution of the entire boiler system. In areas like the main steam outlet header and the reheater inlet and outlet headers, any minor leak or malfunction can have serious consequences. The economizer inlet header is also prone to problems due to various factors, and due to its dense tube rows and numerous welds, it is difficult to inspect. In actual applications, because the parameters of the water-cooled wall lower header are much lower than those of the upper header, and the accident rate is also lower, its condition monitoring is often overlooked.

[0004] At present, there is no long-term real-time acquisition of the stress and expansion information of the lower header of an in-service boiler, and it is impossible to accurately obtain the real-time stress state of the lower header. As a result, it is impossible to integrate various data to conduct intelligent real-time monitoring and early warning of the lower header status. Therefore, it is necessary to provide a status monitoring system and method that can greatly improve the safe operation stability of the lower header. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a boiler water-wall lower header structure deformation monitoring system and method, so as to obtain the stress and expansion information and temperature information of the lower header in real time over a long period of time, obtain the stress state of the header in real time, intelligently judge the health status of the header and automatically alarm according to abnormal problems.

[0006] The objective of the present invention is achieved as follows: A boiler water-wall lower header structure deformation monitoring system includes an expansion acquisition module, a strain acquisition module, and a temperature acquisition module, wherein the expansion acquisition module is connected to an expansion processing module, the strain acquisition module is connected to a strain processing module, and the temperature acquisition module is connected to a temperature processing module. The expansion processing module, the strain processing module, and the temperature processing module are all connected to a fiber optic switch, which is connected to a server. The server is equipped with an SIS system, a header stress calculation system, and a storage system. The SIS system includes an early warning program. The server is connected to a client.

[0007] Furthermore, the expansion collection module includes a plurality of expansion collection devices, which are respectively arranged on the lower header to be monitored and the water outlet pipe of the lower header.

[0008] Furthermore, the expansion collection module includes a first expansion collection device and a second expansion collection device. The first expansion collection device is arranged at the left and right ends of the lower header to be monitored, and the second expansion collection device is arranged at the middle position of the lower header to be monitored.

[0009] A first expansion collection device is respectively provided at the left and right ends of the lower header to be monitored, and a second expansion collection device is provided at the middle section of the lower header to be monitored. The first expansion collection device and the second expansion collection device can be used to monitor and collect expansion information at the end and middle sections of the lower header to be monitored, and the collected information is transmitted to the expansion processing module, which processes the relevant information and then transmits the relevant information to the backend server through the optical fiber switch.

[0010] Furthermore, the expansion collection module also includes a third expansion collection device and a fourth expansion collection device. The third expansion collection device is arranged on the lower header water outlet pipe fin between the two lower header water outlet pipes at the leftmost end of the lower header to be monitored, and the fourth expansion collection device is arranged on the lower header water outlet pipe fin between the two lower header water outlet pipes at the rightmost end of the lower header to be monitored.

[0011] The third expansion collection device and the fourth expansion collection device cooperate with the first expansion collection device and the second expansion collection device to monitor and collect expansion information at various positions of the lower header to be monitored.

[0012] Furthermore, the temperature acquisition module includes a plurality of temperature acquisition devices, and each of the temperature acquisition devices is arranged on the lower header water outlet pipe of the lower header to be monitored.

[0013] Furthermore, the number of the temperature collection devices is determined according to the number of the lower header water outlet pipes, and a temperature measuring point is set for each lower header water outlet pipe.

[0014] Furthermore, each temperature measuring point corresponds to a temperature acquisition device, and the temperature acquisition device uses a thermocouple to monitor and acquire temperature information of the lower header water outlet pipe connected to different positions of the lower header to be monitored.

[0015] Furthermore, the strain collection module includes a plurality of strain collection devices, and each of the strain collection devices is respectively arranged on the lower header water outlet pipe connected at both ends of the lower header to be monitored.

[0016] Furthermore, each of the strain collection devices is respectively arranged on the , , and , water outlet pipes of the lower header tank connected to the left and right ends of the lower header tank to be monitored.

[0017] Furthermore, the strain collection device is located at the pipe seat fillet weld connecting the corresponding lower header outlet pipe and the lower header to be monitored, and the strain collection device uses high-temperature strain gauges to monitor and collect strain information at each position.

[0018] Furthermore, two fiber optic switches are provided, and the two fiber optic switches form a fiber optic transmission network to transmit data information to the server at the back end.

[0019] A monitoring method based on the above-mentioned boiler water wall lower header structure deformation monitoring system comprises the following steps: S1. Establish a finite element analysis model based on the design data of the water-cooled wall lower header; S2, the header stress calculation system collects data from the SIS system, expansion processing module, strain processing module, and temperature processing module, and calculates the header thermal displacement and stress data; S3. The header stress calculation system sets different warning intervals according to the boiler operating status; S4. The header stress calculation system obtains various allowable states through the SIS system and automatically adjusts the warning range; S5. The header stress calculation system obtains different warning values according to the data changes in each interval. When operating in each interval, when the displacement of the header to be monitored is greater than the design thermal displacement allowable threshold L, the temperature of the header to be monitored is greater than the design allowable threshold T, and the stress is greater than the alarm threshold S, an alarm signal is sent to the client.

[0020] Beneficial effects of the present invention: A boiler water-wall lower header structural deformation monitoring system of the present invention includes an expansion acquisition module 8, a strain acquisition module 11, and a temperature acquisition module 12. The expansion acquisition module 8 is connected to an expansion processing module 9, the strain acquisition module 11 is connected to a strain processing module 10, and the temperature acquisition module 12 is connected to a temperature processing module 13. The expansion processing module 9, the strain processing module 10, and the temperature processing module 13 are all connected to a fiber optic switch 14, and the fiber optic switch 14 is connected to a server 15. The server 15 is provided with an SIS system 16, a header stress calculation system 17, and a storage system 18. The SIS system includes an early warning program 19, and the server 15 is connected to a client 20. The lower header status data is monitored in real time by the expansion acquisition module 8, the strain acquisition module 11, and the temperature acquisition module 12. The server program then determines whether the displacement signal and temperature signal of the header meet the boiler operation permission requirements. A dynamic early warning program is set to alarm when abnormal data occurs to ensure safe operation of the header. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a schematic diagram of a boiler water wall lower header structure deformation monitoring system.

[0023] Figure 2 The diagram is a working logic diagram of a boiler water wall lower header structure deformation monitoring system.

[0024] Figure 3 The figure is a schematic diagram of the working process of a method for deforming the lower header structure of a boiler water-cooled wall. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to the accompanying drawings.

[0026] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0028] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship and movement status between the various components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly. The connection can be a direct connection or an indirect connection.

[0029] like Figure 1-3 As shown, a boiler water-wall lower header structure deformation monitoring system of the present invention includes an expansion acquisition module 8, a strain acquisition module 11, and a temperature acquisition module 12. The expansion acquisition module 8 is connected to an expansion processing module 9, the strain acquisition module 11 is connected to a strain processing module 10, and the temperature acquisition module 12 is connected to a temperature processing module 13. The expansion processing module 9, the strain processing module 10, and the temperature processing module 13 are all connected to a fiber optic switch 14, which is connected to a server 15. The server 15 is provided with an SIS system 16, a header stress calculation system 17, and a storage system 18. The SIS system includes an early warning program 19. The server 15 is connected to a client 20.

[0030] The working medium flows into the monitored lower header 1 from the lower header water inlet pipe 2 and then flows out from the lower header water outlet pipe 3. The lower header water outlet pipe fin 4 is used to connect two adjacent lower header water outlet pipes 3.

[0031] Furthermore, in one embodiment, the expansion collection module 8 includes a plurality of expansion collection devices 5 , which are respectively arranged on the lower header 1 to be monitored and the water outlet pipe 3 of the lower header.

[0032] Furthermore, in one embodiment, the expansion collection module 8 includes a first expansion collection device and a second expansion collection device, the first expansion collection device is arranged at the left and right ends of the lower header 1 to be monitored, and the second expansion collection device is arranged at the middle section of the lower header 1 to be monitored.

[0033] In one embodiment, a first expansion collection device is respectively provided at the left and right ends of the lower header 1 to be monitored, and a second expansion collection device is provided at the middle position of the lower header 1 to be monitored. The first expansion collection device and the second expansion collection device can be used to monitor and collect expansion information at the end and middle positions of the lower header 1 to be monitored, and the collected information is transmitted to the expansion processing module 9, which processes the relevant information and then transmits the relevant information to the backend server 15 through the optical fiber switch 14.

[0034] In another embodiment, three first expansion collection devices are respectively provided at the left and right ends of the lower header 1 to be monitored, and three second expansion collection devices are provided at the middle section of the lower header 1 to be monitored. Through the redundant design of the three first expansion collection devices and the three second expansion collection devices, accurate expansion information monitoring and collection at the end and middle sections of the lower header 1 to be monitored are ensured, and distortion of monitoring information caused by failure of a single collection device due to damage or the like is avoided. The collected information is then transmitted to the expansion processing module 9, which processes the relevant information and then transmits the relevant information to the backend server 15 through the optical fiber switch 14.

[0035] Furthermore, in one embodiment, the expansion collection module 8 also includes a third expansion collection device and a fourth expansion collection device, the third expansion collection device is arranged on the lower header water outlet pipe fin 4 between the two lower header water outlet pipes 3 at the leftmost end of the lower header 1 to be monitored, and the fourth expansion collection device is arranged on the lower header water outlet pipe fin 4 between the two lower header water outlet pipes 3 at the rightmost end of the lower header 1 to be monitored.

[0036] The third expansion collection device and the fourth expansion collection device cooperate with the first expansion collection device and the second expansion collection device to monitor and collect expansion information at various positions of the lower header 1 to be monitored, and transmit the collected information to the expansion processing module 9 respectively. After the expansion processing module 9 processes the relevant information, the relevant information is transmitted to the backend server 15 through the optical fiber switch 14.

[0037] Furthermore, in one embodiment, the first expansion collection device, the second expansion collection device, the third expansion collection device and the fourth expansion collection device all use expansion collection sensors to monitor and collect expansion information at various positions of the lower header 1 to be monitored.

[0038] Furthermore, in one embodiment, the temperature acquisition module 12 includes a plurality of temperature acquisition devices 7 , each of which is disposed on the lower header water outlet pipe 3 of the lower header 1 to be monitored.

[0039] Furthermore, in one embodiment, the number of the temperature collecting devices 7 is determined according to the number of the lower header water outlet pipes 3 , and one temperature measuring point is set for every 10 lower header water outlet pipes 3 .

[0040] Furthermore, in one embodiment, each temperature measuring point corresponds to one of the temperature acquisition devices 7, and the temperature acquisition device 7 uses a thermocouple to monitor and collect temperature information of the lower header water outlet pipe 3 connected at different positions of the lower header 1 to be monitored, and transmits the collected information to the temperature processing module 13, which processes the relevant information and then transmits the relevant information to the backend server 15 through the optical fiber switch 14.

[0041] Furthermore, in one embodiment, the strain acquisition module 11 includes a plurality of strain acquisition devices 6 , and each of the strain acquisition devices 6 is respectively provided on the lower header water outlet pipe 3 connected at both ends of the lower header 1 to be monitored.

[0042] Furthermore, in one embodiment, each of the strain collection devices 6 is respectively provided on the first, second and third lower header water outlet pipes 3 connected to the left and right ends of the lower header 1 to be monitored.

[0043] Furthermore, in one embodiment, the strain collection device 6 is located at the pipe seat fillet weld connecting the corresponding lower header water outlet pipe 3 and the lower header 1 to be monitored. The strain collection device 6 uses a high-temperature strain gauge to monitor and collect strain information at each position, and transmits the collected information to the strain processing module 10. The strain processing module 10 processes the relevant information and then transmits the relevant information to the backend server 15 through the optical fiber switch 14.

[0044] Furthermore, in one embodiment, two fiber optic switches 14 are provided, and the two fiber optic switches 14 form a fiber optic transmission network to transmit data information to the server 15 at the back end.

[0045] A monitoring method based on the above-mentioned boiler water wall lower header structure deformation monitoring system comprises the following steps: S1. Establish a finite element analysis model based on the design data of the water-cooled wall lower header; S2, the header stress calculation system collects data from the SIS system, expansion processing module, strain processing module, and temperature processing module, and calculates the header thermal displacement and stress data; S3, the header stress calculation system sets different warning intervals according to the boiler operating status; The warning intervals include before water supply, before ignition, before start-up, before grid connection, load 200MW, load 300MW, load 400MW, load 500MW, load 600MW, load 700MW, load 800MW, load 900MW, load 1000MW; S4. The header stress calculation system obtains various allowable states through the SIS system and automatically adjusts the warning range; S5. The header stress calculation system obtains different warning values according to the data changes in each interval. When operating in each interval, when the displacement of the header to be monitored is greater than the design thermal displacement allowable threshold L, the temperature of the header to be monitored is greater than the design allowable threshold T, and the stress is greater than the alarm threshold S, an alarm signal is sent to the client.

[0046] In summary, a boiler water-wall lower header structural deformation monitoring system according to the present invention includes an expansion acquisition module 8, a strain acquisition module 11, and a temperature acquisition module 12. The expansion acquisition module 8 is connected to an expansion processing module 9, the strain acquisition module 11 is connected to a strain processing module 10, and the temperature acquisition module 12 is connected to a temperature processing module 13. The expansion processing module 9, the strain processing module 10, and the temperature processing module 13 are all connected to a fiber optic switch 14, which is connected to a server 15. The server 15 is provided with a SIS system 16, a header stress calculation system 17, and a storage system 18. The SIS system includes an early warning program 19, and the server 15 is connected to a client 20. The expansion acquisition module 8, the strain acquisition module 11, and the temperature acquisition module 12 monitor the status data of the lower header in real time. The server program then determines whether the displacement signal and temperature signal of the header meet the boiler operation requirements. A dynamic early warning program is set to issue an alarm when abnormal data occurs, ensuring the safe operation of the header.

[0047] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0048] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.

Claims

1. A boiler water wall lower header structure deformation monitoring system, characterized in that: It includes an expansion acquisition module, a strain acquisition module and a temperature acquisition module. The expansion acquisition module is connected to an expansion processing module, the strain acquisition module is connected to a strain processing module, and the temperature acquisition module is connected to a temperature processing module. The expansion processing module, the strain processing module and the temperature processing module are all connected to a fiber optic switch, and the fiber optic switch is connected to a server. The server is equipped with an SIS system, a header stress calculation system and a storage system. The SIS system includes an early warning program. The server is connected to a client.

2. A boiler water wall lower header structure deformation monitoring system according to claim 1, characterized in that: The expansion collection module includes a plurality of expansion collection devices, which are respectively arranged on the lower header to be monitored and the water outlet pipe of the lower header.

3. A boiler water wall lower header structure deformation monitoring system according to claim 2, characterized in that: The expansion collection module includes a first expansion collection device and a second expansion collection device. The first expansion collection device is arranged at the left and right ends of the lower header to be monitored, and the second expansion collection device is arranged at the middle section of the lower header to be monitored.

4. A boiler water wall lower header structure deformation monitoring system according to claim 3, characterized in that: The expansion collection module also includes a third expansion collection device and a fourth expansion collection device. The third expansion collection device is arranged on the lower header water outlet pipe fin between the two lower header water outlet pipes at the leftmost end of the lower header to be monitored, and the fourth expansion collection device is arranged on the lower header water outlet pipe fin between the two lower header water outlet pipes at the rightmost end of the lower header to be monitored.

5. The boiler water wall lower header structure deformation monitoring system according to claim 1, characterized in that: The temperature acquisition module includes a plurality of temperature acquisition devices, each of which is arranged on a water outlet pipe of a lower header to be monitored.

6. A boiler water wall lower header structure deformation monitoring system according to claim 5, characterized in that: The number of the temperature collection devices is determined according to the number of the lower header water outlet pipes, and a temperature measuring point is set for each lower header water outlet pipe.

7. The boiler water wall lower header structure deformation monitoring system according to claim 1, characterized in that: The strain collection module includes a plurality of strain collection devices, each of which is respectively arranged on a lower header water outlet pipe connected at both ends of the lower header to be monitored.

8. A boiler water wall lower header structure deformation monitoring system according to claim 7, characterized in that: Each of the strain collection devices is respectively arranged on the first, second, and third lower header water outlet pipes connected to the left and right ends of the lower header to be monitored.

9. The boiler water wall lower header structure deformation monitoring system according to claim 1, characterized in that: Two fiber optic switches are provided, and the two fiber optic switches form a fiber optic transmission network to transmit data information to the server at the back end.

10. A monitoring method for a boiler water wall lower header structure deformation monitoring system according to any one of claims 1 to 9, characterized in that: The monitoring method comprises the following steps: S1. Establish a finite element analysis model based on the design data of the water-cooled wall lower header; S2, the header stress calculation system collects data from the SIS system, expansion processing module, strain processing module, and temperature processing module, and calculates the header thermal displacement and stress data; S3, the header stress calculation system sets different warning intervals according to the boiler operating status; S4. The header stress calculation system obtains various allowable states through the SIS system and automatically adjusts the warning range; S5. The header stress calculation system obtains different warning values according to the data changes in each interval. When operating in each interval, when the displacement of the header to be monitored is greater than the design thermal displacement allowable threshold L, the temperature of the header to be monitored is greater than the design allowable threshold T, and the stress is greater than the alarm threshold S, an alarm signal is sent to the client.

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