Intelligent pressure maintaining instrument for gas pipeline pressure test and test method thereof

Abstract

The invention discloses an intelligent pressure maintaining instrument for a gas pipeline pressure test and a test method thereof, and the intelligent pressure maintaining instrument comprises a metal housing which is internally provided with a main circuit board; the atmospheric pressure sensor and the temperature and pressure integrated sensor are both arranged on the metal shell; the detection circuit is arranged on the main circuit board and is used for detecting natural gas pressure, temperature and atmospheric pressure; the control screen is arranged on the metal shell and used for switching interfaces, monitoring the running state of the equipment and setting parameters; the test method comprises the following steps: S1, after a pipeline is pretreated and installed, starting the intelligent pressure maintaining instrument equipment; s2, ensuring that the measuring range and the precision of the pressure maintaining instrument meet test requirements; s3, a sampling program is set in the intelligent pressure maintaining instrument for sampling testing; s4, ending the test; and S5, performing database filing on the actually measured data. The device is high in measurement precision and low in power consumption, can collect data according to test types, and automatically calculates and corrects the pressure drop, so as to automatically judge whether the pipeline meets a preset standard or not.

Description

Technical Field

[0001] The present invention relates to the technical field of gas pipeline quality detection, and in particular to an intelligent pressure maintaining instrument for gas pipeline pressure testing and a testing method thereof. Background Art

[0002] With the widespread use of natural gas as a clean energy, pipeline transportation has become an efficient and economical way to be widely used in urban gas transportation. In order to ensure the safe operation of the gas pipeline, it must be subjected to a strict tightness test before it is officially put into operation to verify whether the sealing performance of the pipeline system meets safety standards.

[0003] Normally, this kind of testing work relies on testers to manually record the various pressure parameters involved in the pressure test process for monitoring. When using gas to test the air tightness of specific components or equipment, it is necessary to connect the gas source and the object to be tested through a pipeline. In this process, leakage at the joint is an important factor affecting the accuracy of the final test results. Therefore, it is particularly important to have high standards for the sealing of pipe joints and to complete pipeline connections conveniently and quickly.

[0004] According to traditional test methods, gas pipeline inspections usually include two stages: strength test and tightness test. The former is designed to evaluate the pipeline's ability to withstand 1.5 times the maximum design pressure, and maintain a stable state for one hour after reaching the pressure to check for any leaks. The latter is implemented after confirming that all interfaces are leak-free. The specific method is to backfill the entire pipeline and then apply a certain pressure (depending on the specific value of the design gas transmission pressure P) and maintain it for at least 24 hours.

[0005] These traditional test steps mainly rely on different types of sensors to measure the internal pressure, temperature and external atmospheric pressure of the pipeline, and the staff will handwrite down the data and their changes, and then judge whether it is qualified according to the corresponding standards and archive the results. Therefore, the existing gas pipeline pressure test method has many problems:

[0006] (1) Low data collection accuracy: Three different types of instruments are used to collect pipeline pressure, pipeline temperature, and atmospheric pressure. Due to the different installation locations of the instruments, the pressure and temperature are unevenly distributed, resulting in large deviations in information such as pressure and temperature. In addition, the inconsistent time nodes and visual errors of manual transcription further reduce the reliability of the data.

[0007] (2) High cost and low efficiency: When engineers conduct strength and tightness tests on long-distance pipelines, they often need to carry out measurements at multiple measurement points. However, the excessive number of measuring instruments used will result in a large amount of work and poor economic efficiency.

[0008] (3) Obvious safety hazards: The minimum safety distance of the pressure test pipeline is 6 meters. However, in actual operation, since the test process needs to be manually recorded, the safety distance often does not meet the requirements. Therefore, if an unexpected situation occurs during the test, it will cause harm to the personnel within the safety distance range;

[0009] (4) Low level of intelligence: The existing market instruments lack abnormal alarm functions during the strength / tightness test, such as abnormal pressure increase, abnormal pressure relief, and lack of judgment on test results;

[0010] (5) On-site data collection is done manually, which involves subjective factors. In addition, handwritten records are inconvenient to store and query. If data needs to be entered into the system for future reference, additional labor costs will be required.

[0011] To this end, the present application specifically proposes an intelligent pressure maintaining instrument for gas pipeline pressure testing to solve the above technical problems. Summary of the invention

[0012] The main purpose of the present invention is to provide an intelligent pressure maintaining instrument for gas pipeline pressure testing to solve the technical problems raised in the background technology.

[0013] The present invention adopts the following technical solutions to solve the above technical problems:

[0014] An intelligent pressure maintaining instrument for gas pipeline pressure test, comprising:

[0015] A metal casing, wherein a main circuit board is arranged inside, and the metal casing is grounded to shield electromagnetic interference;

[0016] The atmospheric pressure sensor and the integrated temperature and pressure sensor are both arranged on the metal housing;

[0017] The detection circuit is arranged on the main circuit board and is used for detecting the natural gas pressure, temperature and atmospheric pressure;

[0018] The battery compartment is set inside the metal shell and is used to install and fix the battery and optimize the wiring;

[0019] The control screen is arranged on the metal housing and is composed of a membrane switch and a liquid crystal screen. The membrane switch and the liquid crystal screen are used together to switch interfaces, monitor the operating status of the equipment and set parameters;

[0020] The external antenna is installed on the metal casing to enhance the IoT communication signal.

[0021] Preferably, a group of ultra-low power MCU based on ARM architecture for logic operation and program control and a group of NB-IOT communication modules connected to the ultra-low power MCU through USART communication, and the detection circuit uploads the data collected in the test to the cloud platform through the NB-IOT module;

[0022] Preferably, the ultra-low power consumption MCU is electrically connected to a control screen for performing corresponding settings and control on the pressure recorder;

[0023] Preferably, the battery inside the battery compartment is connected to the ultra-low power MCU via an LDO voltage stabilizing circuit and an undervoltage detection circuit, and the LDO voltage stabilizing circuit is used to stabilize the battery voltage to 3V;

[0024] Preferably, an analog switch is connected to the connection circuit between the undervoltage detection circuit and the ultra-low power consumption MCU, and the analog switch is connected to an atmospheric pressure sensor and an integrated temperature and pressure sensor for shutting down a designated circuit to reduce system power consumption.

[0025] Preferably, an amplifier circuit connected to the analog switch is also provided on the main circuit board, and the amplifier circuit is connected to the atmospheric pressure sensor and the temperature-pressure integrated sensor for amplifying the voltage signal generated by the sensor in the detection circuit.

[0026] Preferably, the metal shell is composed of a front cover, a rear cover and an instrument case made of aluminum alloy, the front cover, the rear cover and the instrument case are all threadedly connected, and sealing rubber is used to fill the gaps between the front cover, the rear cover and the instrument case to block external impurities.

[0027] A test method of an intelligent pressure maintaining instrument, using any of the above-mentioned intelligent pressure maintaining instruments for gas pipeline pressure testing, specifically comprising the following steps:

[0028] S1. Register the information of the pressure maintaining instrument with metrological certification into the database, lay the pipeline, install the mechanical spring pressure gauge, pressurize the air compressor to the test pressure, wait for the pressure in the pipeline to stabilize, close the instrument valve of the mechanical spring pressure gauge, replace the mechanical spring pressure gauge with the instrument of the pressure maintaining instrument, open the valve and start the intelligent pressure maintaining instrument equipment;

[0029] S2. Create an electronic test work order, fill in the intelligent pressure maintaining instrument equipment information and pipeline information, and compare the range and accuracy of the intelligent pressure maintaining instrument based on the test work order. If the range and accuracy do not meet the preset test requirements, prompt the violation information and stop the work order;

[0030] S3. Upload information including equipment connection status and test pressure value. The external ERP system sends instructions to the current test instrument through the IOT platform. The intelligent pressure maintaining instrument has a built-in sampling program. The instrument performs sampling operations through the intelligent pressure maintaining instrument, starts sampling at the specified time and waits for the test to end. During the test, the sampling program is used to monitor real-time test data, data change trends, and calculated real-time corrected pressure drop values ​​as sampling parameters. If data abnormalities occur during the test, the system automatically alarms and files through the external ERP system. The alarm message is sent to the designated terminal to determine whether to terminate the test early or continue the test operation;

[0031] S4. After the test is completed, an end message is sent to the designated terminal, and the test is ended after uploading the information including the equipment connection status and the test pressure value again. The external ERP system sends instructions to the instrument end through the IOT platform, and the instrument stops sampling and data uploading. The external ERP system collects data and calculates the test results through the standard formula to generate an engineering report;

[0032] S5. After the engineering report is manually confirmed, the external ERP system will file all the measured data and related reports during the test in the database.

[0033] Preferably, the specific steps of the sampling program in step S3 for data sampling include:

[0034] L1. Mean value processing: collect n sets of data within the specified time t seconds, and perform mean value processing on the n sets of data. The processing result is regarded as the sampling value at this moment:

[0035]

[0036] in is the sampling value, x i is the i-th group of data, n is the total number of collected groups;

[0037] L2. Automatic correction of qualified standards: Automatically modify the qualified standards [ΔP] according to the length, material and diameter of the pipeline laid during the test;

[0038] L3. Determine whether the actual allowable pressure drop ΔP′ meets the standard based on the modified qualified standard [ΔP]:

[0039]

[0040] Where H1 is the pipeline pressure before the test, B1 is the atmospheric pressure before the test, H2 is the pipeline pressure after the test, B2 is the atmospheric pressure after the test, t2 is the medium temperature in the pipeline before the test, and t1 is the medium temperature in the pipeline before the test.

[0041] Preferably, the specific operation steps of automatically correcting the qualified standard in the L2 step include:

[0042] If the pipeline laid during the test is made of steel pipe or plastic material, and the design pressure P≤5Kpa, there are:

[0043]

[0044] If the pipeline laid during the test is made of steel pipe and the design pressure P>5Kpa, then:

[0045]

[0046] If the pipes laid during the test are made of plastic and the design pressure P>5Kpa, then:

[0047]

[0048] Where ΔP is the initial allowable pressure drop, T is the test duration, d n is the inner diameter of the nth pipe, l n is the length of the nth pipe.

[0049] Preferably, the data abnormality in step S3 is determined by a preset pressure relief determination formula under abnormal pressure increase, and the pressure relief determination formula is:

[0050] |x n -x1|≥5%R

[0051] Among them, x n is the nth sampling pressure value, n is the number of sampling groups, and R is the preset test pressure standard.

[0052] On the other hand, the present invention further discloses a computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor executes the steps of the above method.

[0053] On the other hand, the present invention further discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the above method.

[0054] It can be seen from the above technical solution that the present invention provides an intelligent pressure maintaining instrument for gas pipeline pressure testing. Compared with the prior art, the present invention has the following advantages:

[0055] 1. The present invention has a compact, delicate and reliable structure. It is an instrument that integrates pipeline pressure, pipeline temperature and atmospheric pressure. It has high measurement accuracy and low power consumption. It can automatically collect data according to the specification requirements based on the test type, and automatically calculate the corrected pressure drop. The qualified standard takes into account the pipeline material, caliber, length and test duration factors, and can automatically determine whether the pipeline is more in line with the actual application standards.

[0056] 2. The present invention can simultaneously measure the atmospheric pressure, the gas pressure in the pipeline, and the temperature in the pipeline and is lightweight. It can automatically sample multiple data simultaneously, thereby reducing measurement errors and reducing the workload of engineering personnel.

[0057] 3. The present invention can monitor abnormal pressure increase and abnormal pressure relief in the pipeline during the test, avoid illegal behaviors such as pressure increase in the middle of the test by engineering personnel, and provide early warning of leakage points in the pipeline.

[0058] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become easy to understand through the following description. Of course, it is not necessary to achieve all of the advantages described above simultaneously for any product implementing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0060] Figure 1 It is a schematic diagram of the overall structure of the pressure maintaining device of the present invention;

[0061] Figure 2 It is a schematic diagram of the structural disassembly of the pressure maintaining device of the present invention;

[0062] Figure 3 It is a schematic diagram of the circuit hardware framework of the pressure maintaining device of the present invention;

[0063] Figure 4 It is a schematic diagram of the test operation flow of the pressure maintaining device of the present invention.

[0064] In the figure:

[0065] 1. Membrane switch; 2. Front cover; 3. LCD screen; 4. Main circuit board; 5. Sealing rubber; 6. Instrument case; 7. Atmospheric pressure sensor; 8. Antenna; 9. Battery compartment; 10. Back cover; 11. Temperature and pressure integrated sensor. DETAILED DESCRIPTION

[0066] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0067] In the embodiment, see Figures 1 to 4 .

[0068] like Figure 1 and Figure 2 As shown, an intelligent pressure maintaining instrument for gas pipeline pressure testing proposed in an embodiment of the present invention includes:

[0069] A metal casing, wherein a main circuit board 4 is arranged inside, and the metal casing is grounded to shield electromagnetic interference;

[0070] The atmospheric pressure sensor 7 and the temperature and pressure integrated sensor 11 are both arranged on the metal housing;

[0071] The detection circuit is arranged on the main circuit board 4 and is used for detecting the natural gas pressure, temperature and atmospheric pressure;

[0072] The battery compartment 9 is arranged inside the metal housing and is used to install and fix the battery and optimize the wiring;

[0073] The control screen is arranged on the metal housing and is composed of a membrane switch 1 and a liquid crystal screen 3. The membrane switch 1 and the liquid crystal screen 3 are used together to switch interfaces, monitor the operating status of the equipment and set parameters;

[0074] The external antenna 8 is arranged on the metal casing and is used to enhance the communication signal of the Internet of Things.

[0075] Further, such as Figure 3 As shown, the detection circuit includes a set of ultra-low power MCU based on ARM architecture for logic operation and program control and a set of NB-IOT communication modules connected to the ultra-low power MCU through USART. The detection circuit uploads the data collected in the test to the cloud platform through the NB-IOT module;

[0076] The ultra-low power MCU is electrically connected to a control screen for setting and controlling the pressure recorder accordingly;

[0077] The battery inside the battery compartment 9 is connected to the low-power MCU through an LDO voltage regulator circuit and an undervoltage detection circuit. The LDO voltage regulator circuit is used to stabilize the battery voltage to 3V;

[0078] An analog switch is connected to the connection circuit between the undervoltage detection circuit and the low-power MCU. The analog switch is connected to the atmospheric pressure sensor 7 and the temperature-pressure integrated sensor 11 for shutting down the specified circuit to reduce system power consumption.

[0079] In addition, reference Figure 3 In a specific implementation process, an amplifier circuit connected to the analog switch is also provided on the main circuit board 4, and the amplifier circuit is connected to the atmospheric pressure sensor 7 and the temperature and pressure integrated sensor 11, which is used to amplify the voltage signal generated by the sensor in the detection circuit.

[0080] It can also be supplemented that the metal shell is composed of a front cover 2, a rear cover 10 and an instrument case 6 made of aluminum alloy. The front cover 2, the rear cover 10 and the instrument case 6 are all connected by threads, and a sealing rubber 5 is used to fill the gap between the front cover 2, the rear cover 10 and the instrument case 6 to block external impurities.

[0081] At this time, since the intelligent pressure maintaining instrument is connected to the high-precision instrument and connected to the gas pipeline, the pressure test operation of the gas pipeline can be carried out.

[0082] On the other hand, the present invention also discloses a test method of an intelligent pressure maintaining instrument, using the intelligent pressure maintaining instrument for gas pipeline pressure test specifically used in the above embodiment to specify corresponding test operations, such as Figure 4 As shown, the specific steps include:

[0083] (1) Preset pipeline strength and tightness test standards:

[0084] (a) Strength test standard:

[0085] a1. Test medium: Clean water is generally used as the test medium. When the pipeline design pressure is less than or equal to 0.8MPa, gas can also be used for testing, but effective safety measures must be taken;

[0086] a2. Test pressure:

[0087] When water is used as the test medium, the test pressure should be 1.5 times the design pressure, but not less than 0.6MPa;

[0088] When gas is used as the test medium, the test pressure should be 1.15 times the design pressure, but not less than 0.1 MPa;

[0089] a3. Stabilization time: After reaching the test pressure, the stabilization time should be determined according to the pipe material and pipe diameter. Generally, the stabilization time should be no less than 10 minutes (the specific time may vary depending on factors such as region and project requirements);

[0090] a4. Qualification standard: If there is no obvious deformation, leakage or pressure drop in the pipeline during the pressure stabilization time (based on the pressure gauge reading), the strength test is qualified;

[0091] (b) Tightness test standards:

[0092] b1. Test medium: Air is generally used as the test medium, but in special cases, other gases can also be used according to design requirements;

[0093] b2. Test pressure: should be the design pressure and should not be less than 0.1MPa;

[0094] b3. Pressure stabilization time: The pressure stabilization time shall not be less than 24 hours. For some pipelines with special requirements, the pressure stabilization time may be longer.

[0095] b4. Qualification standard: During the pressure stabilization time, record the pressure value at least once every hour, and it is qualified when the corrected pressure drop is less than 133Pa;

[0096] (2) The engineering staff shall register the information of the pressure maintaining instrument with metrological certification into the database in advance. The registration information includes: the pressure maintaining instrument SN code, IMEI number, instrument range, instrument accuracy, instrument certification certificate number, and the effective date and expiration date of the certification;

[0097] (3) The engineering staff laid the pipeline, installed the mechanical spring pressure gauge, and pressurized the air compressor to the test pressure, and waited for the pressure in the pipeline to stabilize;

[0098] (4) Close the instrument valve of the mechanical spring pressure gauge, connect the intelligent pressure maintaining device provided in the above embodiment to the pipeline, replace the mechanical spring pressure gauge with the instrument of the pressure maintaining device, press the power button of the device, open the valve and start the intelligent pressure maintaining device;

[0099] It should be noted that the replaced test instruments need to be registered and filed on the engineering management platform before being put into use, to avoid the use of some instruments without metrological certification and explosion-proof certification, and to provide data authenticity and reliability of test results;

[0100] (5) Open the engineering management software APP on the smart terminal (mobile phone, etc.), create an electronic test work order, fill in the equipment information of the intelligent pressure maintaining instrument and engineering information including test type, test duration, pipeline design pressure, pipeline material, pipeline inner diameter, and pipeline length;

[0101] (6) After creating the test work order, the smart terminal (mobile phone, etc.) scans the QR code on the instrument and compares the range and accuracy of the intelligent pressure maintaining instrument based on the test work order. If the instrument has metrological certification and is within the validity period, and the range and accuracy meet the test requirements, the next step can be continued. If it does not meet the preset test requirements, a violation message will be prompted and the work order will be stopped;

[0102] (7) The engineering staff takes photos of the site, which contain key information such as equipment connection status and test pressure value. The test start button can be pressed only after uploading;

[0103] (8) The external ERP system sends instructions to the current test instrument through the IOT platform. The intelligent pressure maintaining instrument has a built-in sampling program. The instrument performs the sampling operation through the intelligent pressure maintaining instrument and starts sampling at the specified time. At this time, the engineering personnel should retreat to the safe distance specified in the specification and wait for the test to end;

[0104] The instrument here can measure atmospheric pressure, gas pressure in pipelines, and temperature in pipelines at the same time. It is lightweight and can automatically sample multiple data at the same time, which reduces measurement errors and workload of engineers. It is cost-effective and data authenticity can be guaranteed.

[0105] (9) During the test, engineers can use the engineering management software APP to view and monitor real-time test data, data change trends, and calculated real-time corrected pressure drop and other sampling parameters through the sampling program;

[0106] At this time, the data processing steps of the sampling program for data sampling include:

[0107] L1. Mean value processing: collect n sets of data within the specified time t seconds, and perform mean value processing on the n sets of data. The processing result is regarded as the sampling value at this moment:

[0108]

[0109] in is the sampling value, x i is the i-th group of data, n is the total number of collected groups;

[0110] L2. Automatic correction of qualified standards: Automatically modify the qualified standards [ΔP] according to the length, material and diameter of the pipeline laid during the test, specifically:

[0111] If the pipeline laid during the test is made of steel pipe or plastic material, and the design pressure P≤5Kpa, there are:

[0112]

[0113] If the pipeline laid during the test is made of steel pipe and the design pressure P>5Kpa, then:

[0114]

[0115] If the pipes laid during the test are made of plastic and the design pressure P>5Kpa, then:

[0116]

[0117] Where ΔP is the initial allowable pressure drop, T is the test duration, d n is the inner diameter of the nth pipe, l n is the length of the nth pipe;

[0118] L3. Determine whether the actual allowable pressure drop ΔP′ meets the standard based on the modified qualified standard [ΔP]:

[0119]

[0120] Where H1 is the pipeline pressure before the test, B1 is the atmospheric pressure before the test, H2 is the pipeline pressure after the test, B2 is the atmospheric pressure after the test, t2 is the medium temperature in the pipeline before the test, and t1 is the medium temperature in the pipeline before the test;

[0121] (10) If data anomalies occur during the process, the system will automatically alarm and file the information through the external ERP system. The alarm message will be sent to the terminal (mobile phone, etc.) of the relevant engineering personnel. The engineering personnel will decide whether to terminate the test early or continue the test operation based on the actual situation.

[0122] At this time, the data abnormality is determined by the preset abnormal pressure relief judgment formula, and the pressure relief judgment formula is:

[0123] |x n -x1|≥5%R

[0124] Among them, x n is the nth sampling pressure value, n is the number of sampling groups, R is the preset test pressure standard, generally the initial sampling pressure value x1;

[0125] At this time, the instrument can monitor abnormal pressure increase and abnormal pressure relief in the pipeline during the test through intelligent pressure maintaining instrument and sampling program, avoiding illegal behaviors such as pressure increase in the middle of the test by engineering personnel, and early warning of leakage points in the pipeline;

[0126] (11) When the test is completed, the completion message will be pushed to the terminal (mobile phone, etc.) of the relevant engineering personnel;

[0127] It can be supplemented here that the above-mentioned instrument adopts automatic data collection and remote data upload, so the engineering personnel do not have to stay on site to record data all the time, and can also achieve the safe distance of the test in the specification, improve the safety during the test, and the stability and reliability of the data;

[0128] (12) The engineer takes photos of the site, which contain key information such as equipment connection status and test pressure value. After uploading, press the test end button;

[0129] (13) The external ERP system sends instructions to the instrument through the IOT platform, and the instrument stops sampling and data uploading;

[0130] (14) The external ERP system will collect data, calculate the test results through standard formulas and generate engineering reports. After the on-site test personnel confirm that they are correct, they press the submit button and the engineering report will be pushed to the supervision end;

[0131] At this time, the ERP system can automatically give the test results for the uploaded test data, avoiding the heavy calculation workload of engineering personnel, making the data intuitive and reliable, and improving efficiency;

[0132] (15) The supervisor reviews the test project report and on-site photos. After confirming that they are correct, he can press the submit button and the project test is completed;

[0133] (16) The whole process peripheral ERP system will record all measured data and related reports during the test in the database. Since all test data will be recorded and filed on the ERP platform, it is convenient for future traceability and query.

[0134] It should be noted that engineering personnel must operate step by step according to the process specified by the engineering management platform, which reduces the number of illegal operations by engineering personnel and improves the reliability of test results.

[0135] It should also be noted that the above-mentioned operating steps all comply with the preset pipeline strength and tightness test standards.

[0136] In summary, the intelligent pressure-maintaining instrument proposed in the present invention has a compact, delicate and reliable structure, and is an instrument that integrates pipeline pressure, pipeline temperature and atmospheric pressure. It has high measurement accuracy and low power consumption. It can automatically collect data according to the specification requirements according to the test type, and automatically calculate the corrected pressure drop. The qualified standard takes into account the pipeline material, caliber, length and test duration factors, and can automatically determine whether the pipeline is more in line with the actual application standards.

[0137] At the same time, the supporting ERP system is used during the pressure test to determine whether the instrument is compliant, whether the test procedure is compliant, and whether the test process is compliant, and management and monitoring are carried out. Therefore, the test process can be fully digitized, the efficiency is improved by intelligence, and all files can be quickly traced.

[0138] Test example.

[0139] Based on the above embodiments, the present invention can also provide specific test examples to prove the effectiveness of the technical solution in actual use: in the newly laid medium-pressure B-grade gas steel pipe project A with the same diameter, the pipe diameter is □518*8mm and the length is 400 meters:

[0140] After the strength test is passed, a 24-hour tightness test is carried out (from 14:00 noon to 14:00 noon the next day), with records recorded every 5 minutes and samples taken once every 1 hour. The sampling parameters of the pressure holding instrument are shown in the table below:

[0141]

[0142]

[0143] At this time, the inner diameter of the steel pipe is: D = 0.518-0.008*2 = 0.502M

[0144] Substituting into the allowable pressure drop formula, we have:

[0145]

[0146] Therefore, the actual pressure drop is:

[0147]

[0148] Since ΔP′<[ΔP], the newly built medium-pressure B-grade gas steel pipe project with the same diameter has passed the tightness test and can be put into production;

[0149] In addition, if the engineering team increases the pressure during the process, or there is a leak in the pipeline, the obvious pressure reduction can be achieved by:

[0150] |x n -x1|≥5%R

[0151] Take the test at 17 hours as an example:

[0152] |466.12-467.13|=1.01<5%*467.13=23.3565

[0153] So it is not within the alarm range at present.

[0154] In another embodiment provided by the present application, a computer program product including sampling instructions is also provided. When the computer program product is executed on a computer, the computer executes the same sampling method during the test process of the above embodiment.

[0155] It is understandable that the system provided by the embodiment of the present invention corresponds to the method provided by the embodiment of the present invention, and the explanation, examples and beneficial effects of the relevant contents can refer to the corresponding parts in the above method.

[0156] It should also be noted that the above-mentioned terminal devices may also be referred to as terminals, user equipment, mobile stations, mobile terminals, etc. The terminal devices may be mobile phones, smart TVs, wearable devices, tablet computers, computers with wireless transceiver functions, virtual reality terminal devices, augmented reality terminal devices, wireless terminals in industrial control, wireless terminals in unmanned driving, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, etc. The embodiments of the present application do not limit the specific technologies and specific device forms used by the terminal devices.

[0157] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, a computer, a server or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or a data center that includes one or more available media integration. The available medium can be a magnetic medium, (e.g., a floppy disk, a hard disk, a tape), an optical medium, or a semiconductor medium (e.g., a solid-state hard disk), etc.

[0158] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

[0159] In addition, it should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0160] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, in the embodiments of the present invention, "multiple" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. An intelligent pressure maintaining instrument for gas pipeline pressure testing, characterized in that: include: A metal shell, in which a main circuit board (4) is arranged, and the metal shell is grounded to shield electromagnetic interference; The atmospheric pressure sensor (7) and the integrated temperature and pressure sensor (11) are both arranged on the metal housing; A detection circuit is arranged on the main circuit board (4) and is used for detecting natural gas pressure, temperature and atmospheric pressure; A battery compartment (9) is arranged inside the metal housing and is used to install and fix the battery and optimize the wiring; A control screen is arranged on the metal housing and is composed of a membrane switch (1) and a liquid crystal screen (3). The membrane switch (1) and the liquid crystal screen (3) are used in conjunction with each other to switch interfaces, monitor the operating status of the device and set parameters; An external antenna (8) is arranged on the metal casing and is used to enhance the communication signal of the Internet of Things.

2. The intelligent pressure maintaining instrument for gas pipeline pressure testing according to claim 1, characterized in that: A set of ultra-low power MCU based on ARM architecture for logic operation and program control and a set of NB-IOT communication modules connected to the ultra-low power MCU through USART communication. The detection circuit uploads the data collected in the test to the cloud platform through the NB-IOT module; The ultra-low power consumption MCU is electrically connected to a control screen for performing corresponding settings and control on the pressure recorder; The battery inside the battery compartment (9) is connected to the ultra-low power consumption MCU via an LDO voltage stabilizing circuit and an undervoltage detection circuit, wherein the LDO voltage stabilizing circuit is used to stabilize the battery voltage to 3V; An analog switch is connected to the connection circuit between the undervoltage detection circuit and the ultra-low power consumption MCU, and the analog switch is connected to an atmospheric pressure sensor (7) and a temperature-pressure integrated sensor (11) for shutting down a designated circuit to reduce system power consumption.

3. The intelligent pressure maintaining instrument for gas pipeline pressure testing according to claim 2, characterized in that: The main circuit board (4) is also provided with an amplifier circuit connected to the analog switch, and the amplifier circuit is connected to the atmospheric pressure sensor (7) and the temperature-pressure integrated sensor (11) and is used to amplify the voltage signal generated by the sensor in the detection circuit.

4. The intelligent pressure maintaining instrument for gas pipeline pressure testing according to claim 1, characterized in that: The metal housing is composed of a front cover (2), a rear cover (10) and an instrument housing (6) made of aluminum alloy. The front cover (2), the rear cover (10) and the instrument housing (6) are all connected by threads, and sealing rubber (5) is used to fill the gaps between the front cover (2), the rear cover (10) and the instrument housing (6) to block external impurities.

5. A test method for an intelligent pressure-maintaining instrument, characterized in that: The intelligent pressure maintaining instrument for gas pipeline pressure testing according to any one of claims 1 to 4 is used, and the specific steps include: S1. Register the information of the pressure maintaining instrument with metrological certification into the database, lay the pipeline, install the mechanical spring pressure gauge, pressurize the air compressor to the test pressure, wait for the pressure in the pipeline to stabilize, close the instrument valve of the mechanical spring pressure gauge, replace the mechanical spring pressure gauge with the instrument of the pressure maintaining instrument, open the valve and start the intelligent pressure maintaining instrument equipment; S2. Create an electronic test work order, fill in the intelligent pressure maintaining instrument equipment information and pipeline information, and compare the range and accuracy of the intelligent pressure maintaining instrument based on the test work order. If the range and accuracy do not meet the preset test requirements, prompt the violation information and stop the work order; S3. Upload information including equipment connection status and test pressure value. The external ERP system sends instructions to the current test instrument through the IOT platform. The intelligent pressure maintaining instrument has a built-in sampling program. The instrument performs sampling operations through the intelligent pressure maintaining instrument, starts sampling at the specified time and waits for the test to end. During the test, the sampling program is used to monitor real-time test data, data change trends, and calculated real-time corrected pressure drop values ​​as sampling parameters. If data abnormalities occur during the test, the system automatically alarms and files through the external ERP system. The alarm message is sent to the designated terminal to determine whether to terminate the test early or continue the test operation; S4. After the test is completed, an end message is sent to the designated terminal, and the test is ended after uploading the information including the equipment connection status and the test pressure value again. The external ERP system sends instructions to the instrument end through the IOT platform, and the instrument stops sampling and data uploading. The external ERP system collects data and calculates the test results through the standard formula to generate an engineering report; S5. After the engineering report is manually confirmed, the external ERP system will file all the measured data and related reports during the test in the database.

6. The test method of the intelligent pressure maintaining instrument as claimed in claim 5, characterized in that: The specific steps of the sampling program in step S3 for data sampling include: L1. Mean value processing: collect n sets of data within the specified time t seconds, and perform mean value processing on the n sets of data. The processing result is regarded as the sampling value at this moment: in is the sampling value, x i is the i-th group of data, n is the total number of collected groups; L2. Automatic correction of qualified standards: Automatically modify the qualified standards [ΔP] according to the length, material and diameter of the pipeline laid during the test; L3. Based on the modified qualified standard [ΔP], determine whether the actual allowable pressure drop ΔP′ meets the standard: Where H1 is the pipeline pressure before the test, B1 is the atmospheric pressure before the test, H2 is the pipeline pressure after the test, B2 is the atmospheric pressure after the test, t2 is the medium temperature in the pipeline before the test, and t1 is the medium temperature in the pipeline before the test.

7. The test method of the intelligent pressure-maintaining instrument according to claim 6, characterized in that: The specific operation steps of automatically correcting the qualified standard in the L2 step include: If the pipeline laid during the test is made of steel pipe or plastic material, and the design pressure P≤5Kpa, there are: If the pipeline laid during the test is made of steel pipe and the design pressure P>5Kpa, then: If the pipes laid during the test are made of plastic and the design pressure P>5Kpa, then: Where ΔP is the initial allowable pressure drop, T is the test duration, d n is the inner diameter of the nth pipe, l n is the length of the nth pipe.

8. The test method of the intelligent pressure maintaining instrument according to claim 6, characterized in that: The data abnormality in step S3 is determined by a preset pressure relief determination formula under abnormal pressure increase, and the pressure relief determination formula is: |x n -x1|≥5%R Among them, x n is the nth sampling pressure value, n is the number of sampling groups, and R is the preset test pressure standard.

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