Optical fiber sensor packaging adhesive tape for monitoring state of pressure-bearing pipeline and detection method of optical fiber sensor packaging adhesive tape

Abstract

The invention belongs to the field of nuclear power plant pressure-bearing pipeline state monitoring, and particularly relates to an optical fiber sensor packaging adhesive tape for pressure-bearing pipeline state monitoring and a detection method thereof, and the optical fiber sensor packaging adhesive tape comprises a PI optical fiber and a high-temperature adhesive tape; a section of PI optical fiber is fixed on a single-sided high-temperature adhesive tape in a form of a plurality of S bends, one end of the PI optical fiber fixed on the adhesive tape is connected with an ERE tail end reflection eliminator for ensuring signal stability, and the other end of the PI optical fiber fixed on the adhesive tape is connected with an optical fiber flange for accessing a light source. According to the optical fiber sensor adhesive tape, the optical fiber installation and arrangement process is greatly simplified, and the detection reliability and precision can be effectively improved.

Description

Technical Field

[0001] The invention belongs to the field of nuclear power plant pressure pipeline status monitoring, and in particular relates to an optical fiber sensor packaging tape for pressure pipeline status monitoring and a detection method thereof. Background Art

[0002] The pressure pipelines of nuclear power plants are subject to the influence of many factors during operation, including operating temperature, medium pressure, additional bending moment generated by pipeline deadweight, axial force, medium scouring load and corrosion, which are prone to local defects. At present, the status detection of pressure pipelines mainly relies on traditional maintenance methods such as post-maintenance of system operating parameter changes and regular maintenance by manual inspection. The above maintenance methods have the following problems: when the pipeline deteriorates in the early stage, the system operating parameters change slightly and cannot provide effective and timely early warning signals; the frequency of regular maintenance and manual inspection is limited, the work efficiency is low, and it is difficult to identify and locate, and there are problems of untimely maintenance or excessive maintenance and omissions. At the same time, some pipelines that are prone to deterioration may be located in the branch pipes or auxiliary pipes of the system, and the pipeline location is relatively hidden; manual inspections can only focus on accessible areas, and it is difficult to find hidden areas that are inaccessible or difficult to observe through manual inspections.

[0003] Therefore, the existing means and research status of nuclear power plants cannot meet the needs of pressure pipeline status monitoring. Nuclear power plants are eager to meet the needs of pressure pipeline status monitoring by introducing advanced sensing technologies, and OFDR's optical fiber strain sensing technology is one of them.

[0004] However, in actual application, it was found that simply wrapping the PI optical fiber in a "threaded" form on the surface of the metal pipe did not produce good results. The optical fiber packaging process had a significant impact on the reliability and accuracy of the product, limiting the promotion and application of this technology in nuclear power plants. Summary of the invention

[0005] The purpose of the present invention is to provide a fiber optic sensor packaging tape for monitoring the state of a pressure pipeline and a detection method thereof. The fiber optic sensor packaging tape greatly simplifies the fiber optic installation and layout process and can effectively improve the detection reliability and accuracy.

[0006] The technical solution to achieve the purpose of the present invention is:

[0007] A fiber optic sensor packaging tape for monitoring the state of a pressure pipeline includes: a PI optical fiber and a high-temperature tape; a section of the PI optical fiber is fixed on the single-sided high-temperature tape in the form of multiple "S bends", one end of the PI optical fiber fixed on the tape is connected to an ERE tail end reflection eliminator for ensuring signal stability, and the other end is connected to a fiber optic flange for connecting to a light source.

[0008] The "S-bend" form of the PI optical fiber includes a straight section and an elbow section. The straight section is bonded with a high-temperature tape to transmit shear force; the elbow section is suspended in the air and does not participate in the transmission of force.

[0009] The straight section in the "S-bend" of the PI optical fiber is bonded to the high-temperature tape by glue.

[0010] The straight section in the "S-bend" of the PI optical fiber is covered with glass fiber cloth to protect it from external disturbances.

[0011] The lower surface of the high temperature tape is an adhesive layer, which is used for sticking to the pipeline surface.

[0012] The overall shape of the high temperature tape is oval, which is convenient for sticking on the elbow part of the pipe.

[0013] A method for detecting an optical fiber sensor packaging tape for monitoring the state of a pressure pipeline, the method comprising:

[0014] Step 1: Grind and decontaminate the test position on the outer surface of the pipeline test piece;

[0015] Step 2, sticking the optical fiber sensor packaging tape to the outer surface of the pipeline test piece;

[0016] Step 3: Connect the optical fiber sensor, optical fiber demodulator, and data acquisition equipment;

[0017] Step 4: Initialize and zero the data acquisition device to locate the optical fiber measurement point;

[0018] Step 5: Collect optical fiber strain sensing benchmark data to verify the stability of the data acquisition equipment;

[0019] Step 6: Collect real-time optical fiber strain measurement data to determine the real-time status of the pipeline.

[0020] The step 3 includes: the optical fiber sensor on the surface of the pipeline test piece is connected to the optical fiber demodulator through the communication optical fiber; the optical fiber demodulator is connected to the data acquisition device through the Type-c data cable; the optical fiber demodulator and the data acquisition device are connected to their respective power supplies and then connected to the power supply port, and the data acquisition device is turned on.

[0021] In step 4, the optical fiber measuring point position is positioned by spraying liquid nitrogen at the measuring point position.

[0022] The step 6 includes: collecting real-time optical fiber strain measurement data to obtain circumferential strain data at different positions of the pressure pipeline; rendering the strain data in the form of a thermal map to obtain a strain cloud map of each position of the optical fiber sensor packaging tape; and judging the real-time status of the pipeline based on the change of the strain gradient in the strain cloud map.

[0023] The beneficial technical effects of the present invention are:

[0024] 1. The optical fiber sensor packaging tape for monitoring the state of a pressure pipeline provided by the present invention simplifies the optical fiber installation and layout process, lowers the operator's operating threshold, saves the nuclear power plant pipeline operation and maintenance period, and indirectly improves the economic benefits.

[0025] 2. The optical fiber sensor packaging tape for monitoring the state of a pressure pipeline provided by the present invention improves the reliability and accuracy of optical fiber strain testing of pressure pipelines in nuclear power plants, and lays a foundation for the application of advanced sensing technologies represented by optical fiber in nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the original OFDR fiber packaging form and its system layout;

[0027] Figure 2 A schematic diagram of the packaging tape structure of an optical fiber sensor for monitoring the state of a pressure pipeline provided by the present invention;

[0028] Figure 3 A detailed diagram of the PI optical fiber fixation in an optical fiber sensor packaging tape for monitoring the state of a pressure pipeline provided by the present invention;

[0029] Figure 4 It is the measured strain cloud diagram of the packaging tape of the optical fiber sensor at different positions of the pressure pipeline in the embodiment of the present invention. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0031] like Figure 2 As shown, the optical fiber sensor packaging tape for monitoring the state of a pressure pipeline provided by the present invention includes: PI optical fiber, high-temperature tape, and glass fiber cloth.

[0032] A section of PI optical fiber is fixed on a single-sided high-temperature tape in the form of multiple "S bends". One end of the PI optical fiber fixed on the tape is connected to an ERE tail-end reflection eliminator to ensure signal stability, and the other end is connected to a fiber optic flange for connecting to a light source.

[0033] like Figure 2 As shown in the figure, the "S-bend" form of PI optical fiber includes a straight section and an elbow section. The straight section in the "S-bend" of PI optical fiber is glued to the high-temperature tape by glue, which is used to transmit shear force and belongs to the sensing section; the elbow section of the "S-bend" of PI optical fiber is suspended in the air and does not participate in the force transmission. The straight section in the "S-bend" of PI optical fiber, that is, the surface of the sensing section is covered with glass fiber cloth to protect it from external disturbances, such as Figure 3 shown.

[0034] In a specific embodiment, the lower surface of the high temperature tape is an adhesive layer for sticking to the pipe surface; the overall shape of the high temperature tape is designed to be elliptical, which is convenient for sticking to the elbow part of the pipe.

[0035] The present invention provides a method for detecting an optical fiber sensor packaging tape for monitoring the state of a pressure pipeline, which specifically comprises the following steps:

[0036] Step 1: Grind and decontaminate the test position on the outer surface of the pipeline test piece

[0037] The test position on the outer surface of the pipeline test piece was polished and rust removed, and the metal surface was wiped with an alcohol cotton ball to remove stains to meet the conditions for arranging the packaging tape of the optical fiber sensor.

[0038] Step 2: Paste the fiber optic sensor packaging tape on the outer surface of the pipeline test piece

[0039] Tear off a little bit of the protective film of the adhesive layer of the optical fiber sensor packaging tape, and then tear up the film along one side; stick the torn film to the outer surface of the pipe. During the pasting process of the optical fiber sensor packaging tape, you can use a scraper or other hard object to gently press the tape film surface to ensure that the tape adhesive layer is tightly fitted to the outer surface of the pipe.

[0040] Step 3: Connect the fiber optic sensor, fiber optic demodulator, and data acquisition equipment

[0041] Use communication optical fiber to connect the optical fiber sensor on the outer surface of the pipeline test piece to the optical fiber demodulator through the optical fiber flange;

[0042] When the optical fiber demodulator and data acquisition device are completely turned off, connect the two via a Type-c data cable;

[0043] Connect the fiber optic demodulator and data acquisition equipment to their respective power supplies and then connect them to the power supply port, and turn on the data acquisition equipment.

[0044] Step 4: Initialize and zero the data acquisition equipment to locate the fiber measurement point

[0045] Initialize and zero the equipment, and spray liquid nitrogen at the designated measuring point to locate the optical fiber measuring point.

[0046] Step 5: Collect fiber optic strain sensor benchmark data to verify the stability of the data acquisition equipment

[0047] Step 6: Collect real-time optical fiber strain measurement data to determine the real-time status of the pipeline

[0048] Collect real-time optical fiber strain measurement data to obtain hoop strain data at different locations of the pressure pipeline;

[0049] The strain data is rendered by means of a thermal map to obtain the strain cloud map of each position of the optical fiber sensor packaging tape, such as Figure 4 As shown;

[0050] The real-time status of the pipeline is determined by combining the changes in the strain gradient in the strain cloud diagram.

[0051] The present invention is described in detail above with reference to the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims

1. An optical fiber sensor packaging tape for monitoring the state of a pressure pipeline, characterized in that: include: PI optical fiber, high temperature tape; A section of PI optical fiber is fixed on a single-sided high-temperature tape in the form of multiple "S bends". One end of the PI optical fiber fixed on the tape is connected to an ERE tail-end reflection eliminator to ensure signal stability, and the other end is connected to a fiber optic flange for connecting to a light source.

2. The optical fiber sensor packaging tape for monitoring the state of a pressure pipeline according to claim 1, characterized in that: The "S-bend" form of the PI optical fiber includes a straight section and an elbow section. The straight section is bonded with a high-temperature tape to transmit shear force; the elbow section is suspended in the air and does not participate in the transmission of force.

3. The optical fiber sensor packaging tape for monitoring the state of a pressure pipeline according to claim 2, characterized in that: The straight section in the "S-bend" of the PI optical fiber is bonded to the high-temperature tape by glue.

4. The optical fiber sensor packaging tape for monitoring the state of a pressure pipeline according to claim 2, characterized in that: The straight section in the "S-bend" of the PI optical fiber is covered with glass fiber cloth to protect it from external disturbances.

5. The optical fiber sensor packaging tape for monitoring the state of a pressure pipeline according to claim 1, characterized in that: The lower surface of the high temperature tape is an adhesive layer, which is used for sticking to the pipeline surface.

6. The optical fiber sensor packaging tape for monitoring the state of a pressure pipeline according to claim 1, characterized in that: The overall shape of the high temperature tape is oval, which is convenient for sticking on the elbow part of the pipe.

7. A method for detecting an optical fiber sensor packaging tape for monitoring the state of a pressure pipeline, characterized in that: The method comprises: Step 1: Grind and decontaminate the test position on the outer surface of the pipeline test piece; Step 2, sticking the optical fiber sensor packaging tape to the outer surface of the pipeline test piece; Step 3: Connect the optical fiber sensor, optical fiber demodulator, and data acquisition equipment; Step 4: Initialize and zero the data acquisition device to locate the optical fiber measurement point; Step 5: Collect optical fiber strain sensing benchmark data to verify the stability of the data acquisition equipment; Step 6: Collect real-time optical fiber strain measurement data to determine the real-time status of the pipeline.

8. The method for detecting the packaging tape of an optical fiber sensor for monitoring the state of a pressure pipeline according to claim 7, characterized in that: The step 3 includes: the optical fiber sensor on the surface of the pipeline test piece is connected to the optical fiber demodulator through the communication optical fiber; the optical fiber demodulator is connected to the data acquisition device through the Type-c data cable; the optical fiber demodulator and the data acquisition device are connected to their respective power supplies and then connected to the power supply port, and the data acquisition device is turned on.

9. The method for detecting the packaging tape of an optical fiber sensor for monitoring the state of a pressure pipeline according to claim 7, characterized in that: In step 4, the optical fiber measuring point position is positioned by spraying liquid nitrogen at the measuring point position.

10. The method for detecting the packaging tape of an optical fiber sensor for monitoring the state of a pressure pipeline according to claim 7, characterized in that: The step 6 includes: collecting real-time optical fiber strain measurement data to obtain circumferential strain data at different positions of the pressure pipeline; rendering the strain data in the form of a thermal map to obtain a strain cloud map of each position of the optical fiber sensor packaging tape; and judging the real-time status of the pipeline based on the change of the strain gradient in the strain cloud map.

Images