A method and device for judging and selecting feasibility of trenchless repair technology for gas

Abstract

The application provides a method and device for judging feasibility of trenchless repair technology for gas, which comprises the following steps: establishing a basic information database; determining basic parameters according to environmental data of a pipeline to be repaired and in combination with the basic information database; generating a city gas pipeline trenchless repair experiment platform according to the basic parameters, which is used for simulating the pipeline to be repaired; and judging feasibility of the pipeline to be repaired and repair technology by using the city gas pipeline trenchless repair experiment platform. The method can judge feasibility of trenchless repair technology for gas, save manpower and resources, and improve the efficiency of using trenchless repair technology for gas.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of trenchless repair of gas pipelines, and in particular to a method and device for determining the feasibility of trenchless repair of gas pipelines. BACKGROUND

[0002] Urban pipelines are one of the important infrastructures supporting social development and ensuring people's lives, and pipeline maintenance is a necessary means to ensure its normal mechanism and function. Under normal circumstances, pipeline repair is mainly carried out through two repair methods: open repair and trenchless repair.

[0003] Trenchless repair is gradually valued as a low-impact and low-maintenance repair method for infrastructure. However, before trenchless repair is carried out, how to determine whether the trenchless repair technology is feasible becomes an even more important link. On the basis of feasibility, trenchless repair can save manpower and resources, so how to determine whether the trenchless repair technology is feasible becomes a problem to be solved. SUMMARY

[0004] The present application aims to provide a method and device for determining the feasibility of trenchless repair of gas pipelines, which overcomes the above problems or at least partially solves them.

[0005] To achieve the above purpose, the technical solution of the present application is as follows:

[0006] One aspect of the present application provides a method for determining the feasibility of trenchless repair of gas pipelines, comprising:

[0007] Establishing a basic information database, which includes: pressure rating, pipe material, pipe diameter, elbow angle and radius of curvature;

[0008] According to the environmental data of the pipeline to be repaired, combined with the basic information database, the basic parameters are determined, including: the pressure rating of the pipeline to be repaired, the elbow angle of the pipeline to be repaired, the radius of curvature of the pipeline to be repaired, the number of elbows of the pipeline to be repaired, the interval between elbows of the pipeline to be repaired, the number of observation holes, the position of observation holes and the size of observation holes;

[0009] According to the basic parameters, a city gas pipeline trenchless repair experiment platform is generated, which is used to simulate the pipeline to be repaired;

[0010] The feasibility of the pipeline to be repaired is determined by using the city gas pipeline trenchless repair experiment platform;

[0011] The method for determining the feasibility of trenchless repair of gas pipelines comprises the following steps:

[0012] determining the passability index of the pipeline to be repaired and the repair technology;

[0013] determining the roundness index of the pipeline to be repaired and the repair technology;

[0014] determining the air tightness index of the pipeline to be repaired and the repair technology.

[0015] Optionally, the elbow interval of the pipeline to be repaired is calculated by the following formula:

[0016]

[0017] wherein L is the distance of the straight pipe section between two adjacent elbows, R is the curvature radius of the elbow, n is the total number of elbows of the pipeline to be repaired, and t is the safety factor.

[0018] Optionally, the location of the observation hole is set by the following method:

[0019] using the detachable part above the pipe as the observation hole at the cut-off pipe;

[0020] setting the observation hole at the middle of the elbow, setting the observation hole at the 0 point, 3 point and 9 point of the elbow, and setting at least one elbow with both inside and outside observation holes;

[0021] setting the observation hole at the 3 point and 9 point of the straight pipe section between two elbows and the straight pipe section behind the reducing pipe.

[0022] Optionally, the size of the observation hole is set by the following method:

[0023] if it is a straight pipe section or an elbow with R=1.5D, the observation hole is set to have a length L=100-150mm and a width W=(4%-5%)*Π*D;

[0024] if it is an elbow with R=5D, the observation hole is set to have a length L=2*Π*D and a width W=(4%-5%)*Π*D;

[0025] wherein D is the diameter of the pipeline and R is the curvature radius of the elbow.

[0026] Optionally, the determination of the passability index of the pipeline to be repaired and the repair technology comprises:

[0027] determining the speed and traction;

[0028] determining the surface scratch;

[0029] Optionally, the determination of the speed and traction comprises:

[0030] whether the speed is in a preset range when cutting off the pipe, the elbow;

[0031] whether the pulling force is always less than the maximum allowable pulling force F of the repair material during the pulling process, wherein the maximum allowable pulling force F is calculated by the following formula:

[0032] F=nN1F0

[0033] wherein F is the allowable pulling force, F0 is the average breaking strength of the longitudinal single fiber, n is the number of longitudinal fiber strands, and N1 is a safety factor.

[0034] Optionally, the determining the roundness index of the pipe to be repaired and the repair technology comprises:

[0035] Optionally, the determining the roundness index of the pipe to be repaired and the repair technology comprises:

[0036] Optionally, the determining the air tightness index of the pipe to be repaired and the repair technology comprises:

[0037] whether the corrected pressure drop is less than a preset value, wherein the corrected pressure drop is calculated by the following formula:

[0038]

[0039] wherein P' is the corrected pressure drop, H1 and H2 are the pressure gauge readings at the beginning and end of the test, B1 and B2 are the barometer readings at the beginning and end of the test, and t1 and t2 are the pipe medium temperatures at the beginning and end of the test.

[0040] Optionally, the method further comprises: forming a qualitative and quantitative evaluation conclusion on whether the trenchless repair technology is feasible, and outputting the evaluation conclusion.

[0041] Another aspect of the present application provides a device for determining the feasibility of trenchless repair technology for gas and selecting the device, comprising:

[0042] The establishing module is configured to establish a basic information database, wherein the basic information database comprises: pressure rating, pipe material, pipe diameter, elbow angle and curvature radius;

[0043] The determining module is configured to determine basic parameters according to the environmental data of the pipe to be repaired and in combination with the basic information database, wherein the basic parameters comprise: the pressure rating of the pipe to be repaired, the elbow angle of the pipe to be repaired, the curvature radius of the pipe to be repaired, the number of elbows of the pipe to be repaired, the interval between the elbows of the pipe to be repaired, the number of observation holes, the position of the observation holes and the size of the observation holes.

[0044] A generating module is configured to generate a trenchless repair experiment platform for city gas pipelines according to the basic parameters, and the trenchless repair experiment platform is used to simulate the pipeline to be repaired.

[0045] A determining module is configured to determine the feasibility of the pipeline to be repaired and the repair technology by using the trenchless repair experiment platform for city gas pipelines.

[0046] The determining module determines the feasibility of the pipeline to be repaired and the repair technology by using the trenchless repair experiment platform for city gas pipelines in the following ways:

[0047] The passability index of the pipeline to be repaired and the repair technology is determined.

[0048] The roundness index of the pipeline to be repaired and the repair technology is determined.

[0049] The air tightness index of the pipeline to be repaired and the repair technology is determined.

[0050] Optionally, the device further comprises an evaluating module configured to form a qualitative and quantitative evaluation conclusion on whether the trenchless repair technology is feasible, and output the evaluation conclusion.

[0051] Therefore, the method and device for determining the feasibility of trenchless repair technology for city gas pipelines can determine the feasibility of trenchless repair technology for city gas pipelines, save manpower and resources, and improve the efficiency of using trenchless repair technology for city gas pipelines. BRIEF DESCRIPTION OF DRAWINGS

[0052] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0053] Figure 1 The flow chart of the method for determining the feasibility of trenchless repair technology for city gas pipelines provided by the embodiments of the present application;

[0054] Figure 2 The schematic diagram of the commonly used elbow angle of city gas pipeline provided by the embodiments of the present application;

[0055] Figure 3 The schematic diagram of the straight pipe section observation hole shape provided by the embodiments of the present application;

[0056] Figure 4 The schematic diagram of the elbow observation hole shape provided by the embodiments of the present application;

[0057] Figure 5 This is a schematic diagram of the experimental platform design provided in an embodiment of the present invention;

[0058] Figure 6 This is a structural diagram of the device for determining the feasibility of trenchless repair technology for gas supply provided in an embodiment of the present invention. Detailed Implementation

[0059] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0060] Figure 1 This document illustrates a flowchart of the feasibility assessment and selection method for trenchless gas repair technology provided in an embodiment of the present invention. (See attached diagram.) Figure 1 The feasibility assessment and selection method for non-excavation repair technology for gas provided in this embodiment of the invention includes:

[0061] S1. Establish a basic information database, which includes: pressure rating, pipe material, pipe diameter, elbow angle and radius of curvature.

[0062] Specifically, this invention first designs a basic information database for trenchless repair experiments of urban gas pipelines, pre-compiling relevant information on trenchless repair of urban gas pipelines into a basic database to provide a basis for the selection of various parameters in the subsequent experimental platform design.

[0063] The basic information database includes, but is not limited to:

[0064] 1. Pressure rating system and pipe material selection

[0065] The pressure rating system for trenchless repair of urban gas pipelines can be divided into four levels. The first level is the medium and low pressure level, covering pressures of 0.4 MPa and below, with #20 steel or Q235B pipes used. The second level is the sub-high pressure level, covering pressures of 0.4-1.6 MPa, with #20 steel or L245M pipes used. The third level is the high pressure level B, covering pressures of 1.6-2.5 MPa, with #20 steel or L290M pipes used. The fourth level is the high pressure level A, covering pressures of 2.5-4 MPa, with Q345D or L360M pipes used.

[0066] 2. Elbow angle and radius of curvature

[0067] like Figure 2As shown, the commonly used elbow angle of town gas pipeline is 22.5°, 45° and 90°, and the difficulty level of the trenchless repair material passing through the elbow is ranked as 90°>45°>22.5°. According to different pressure levels, the 90° elbow is mainly divided into two kinds of curvature radii, and the 90° elbow of the medium and low pressure gas pipeline is mainly with a curvature radius of 1.5D, and the 90° elbow of the high pressure and above pressure gas pipeline is mainly with a curvature radius of 5D.

[0068] 3. Other specifications:

[0069] Mainly including pipe diameter and wall thickness, the pipe diameter needs to be determined according to the pipe diameter of the pipeline to be repaired, and the wall thickness has no influence on simulation, and after the pipe diameter is determined, the standard wall thickness can be set.

[0070] S2, according to the environmental data of the pipeline to be repaired, and combining the basic information library, the basic parameters are determined, including: the pressure level of the pipeline to be repaired, the elbow angle of the pipeline to be repaired, the curvature radius of the pipeline to be repaired, the number of elbows of the pipeline to be repaired, the elbow interval of the pipeline to be repaired, the number of observation holes, the position of the observation hole and the size of the observation hole.

[0071] The present application completes the overall basic parameter design of the experimental platform through the basic information library and formula design. According to the pipeline to be repaired (existing environmental data), the basic information library is combined to complete the selection of basic parameters such as pipe material, elbow angle and corresponding curvature radius information. Among them, the environmental data mainly refers to pipe diameter, pressure, whether there is an elbow, elbow angle and other pipe information. The pipe diameter of the simulation pipeline is determined according to the pipe diameter. The pipe material is determined according to the pressure, and if there is an elbow, the curvature radius of the elbow can be determined according to the pressure level. According to other pipe information, it can be determined whether the simulation pipeline contains the pipe.

[0072] Among them, the basic parameters include but are not limited to:

[0073] I. Elbow number and spacing

[0074] Combined with the actual laying status of the pipeline, the total number of elbows should not be set too much, and should not be more than 5, and the specific principles are as follows:

[0075] 1. At least one 90° elbow should be set;

[0076] 2. The total number of 22.5° and 45° elbows should be no less than 2

[0077] As an optional embodiment of the present application, the elbow interval of the pipeline to be repaired is calculated by the following formula:

[0078]

[0079] Wherein: L is the distance between the two adjacent elbow straight pipe section, R is the elbow radius, n is the total number of elbows of the pipeline to be repaired, t is the safety factor.

[0080] Wherein, the more the number of elbows, the greater the required traction, and the distance between the adjacent elbow straight pipe section is not easy to be too short, otherwise the required traction will be greatly increased, the length of the straight pipe section between the elbows is set according to the situation of the pipeline to be repaired and designed according to the following formula:

[0081]

[0082] In the formula:

[0083] L----the distance between the two adjacent elbow straight pipe section (m);

[0084] R----elbow radius (m);

[0085] n----the total number of elbows contained in the experimental pipe;

[0086] t----safety factor, R=1.5D, take 0.1-0.5, R=5D, take 0.5-1

[0087] II. Other design requirements

[0088] 1. Prefabricated parts

[0089] Gas pipeline mainly has two kinds of prefabricated parts of wiring and tangent, and the wiring pipe is mainly used for new branch line. The trenchless repair technology is not suitable for the pipeline with wiring pipe, and if there is, it needs to be disconnected at the branch line and repaired in sections. Therefore, the platform design prefabricated parts only contain tangent pipe.

[0090] 2. Reducing pipe

[0091] According to the principle of trenchless repair technology and the situation of the pipeline to be repaired, it is judged whether the experimental platform needs to increase the reducing pipe.

[0092] Wherein, if the technical principle cannot pass through the reducing pipe, the pipe needs to be disconnected here; whether the pipeline to be repaired allows reduced flow operation, if not, it needs to be disconnected; if the pipeline to be repaired allows reduced flow operation after repair, and the technical principle can pass, the simulation pipeline needs to increase the reducing pipe.

[0093] III. Parameters related to passability and safety

[0094] 1. Principles for setting the number and position of observation holes

[0095] (1) The number of observation holes is mainly to meet the observation of key parts repair effect, and the observation holes are set according to the number of elbows and pipe fittings. The number should not be too much to avoid affecting the structure and strength of the pipeline body and the safety of the experiment.

[0096] (2) Observation hole position design principle

[0097] As an optional embodiment of the present application, the observation hole position is set by the following method:

[0098] Using the detachable part above the pipe as the observation hole at the cut-off pipe;

[0099] Setting the observation hole at the middle of the elbow, and setting the observation holes at the 0 point, 3 point and 9 point directions of the elbow, and setting at least one inside and outside observation hole at the same elbow;

[0100] Setting the observation holes at the 3 point and 9 point directions of the straight pipe section between two elbows and the straight pipe section after the reducing pipe.

[0101] Specifically, the detachable method above the pipe can be used for observation at the cut-off pipe, and no additional observation hole is needed.

[0102] The observation hole at the elbow is set at the middle, and the observation holes at the 0 point, 3 point and 9 point directions of the elbow are needed, and the number of observation holes at the same elbow should not exceed 2 to avoid affecting the structural strength of the elbow, and at least one inside and outside observation hole should be set at the same elbow to observe the fitting condition of the key part.

[0103] Setting the observation holes at the 3 point and 9 point directions of the straight pipe section between two elbows and the straight pipe section after the reducing pipe to observe whether the expansion of the repair material is symmetrical.

[0104] (3) Observation hole size design principle (pipe diameter, curvature radius)

[0105] As an optional embodiment of the present application, the observation hole size is set by the following method:

[0106] If it is a straight pipe section or an elbow with R=1.5D, the observation hole is set to have a length L=100-150mm and a width W=(4%-5%)*Π*D;

[0107] If it is an elbow with R=5D, the observation hole is set to have a length L=2*Π*D and a width W=(4%-5%)*Π*D;

[0108] Wherein, D is the pipe diameter, and R is the curvature radius of the elbow.

[0109] A, straight pipe section

[0110] The observation hole shape is as shown in Figure 3 The length L=100-150mm, and the width W (half circle diameter) =(4%-5%)*Π*D, and D is the pipe diameter.

[0111] B, at the elbow with R=1.5D

[0112] The smaller turning radius can adopt the same observation hole size as the straight pipe section, the length L = 100-150mm, and the width W (diameter of semicircle) = (4%-5%)*Pi*D.

[0113] C, R = 5D elbow (R is the curvature radius of the elbow)

[0114] The observation hole shape is as shown in Figure 4 The length L = 2*Pi*D, and the width W (diameter of semicircle) = (4%-5%)*Pi*D.

[0115] S3, according to the basic parameters, a trenchless repair experiment platform for urban fuel pipelines is generated, and the trenchless repair experiment platform for urban fuel pipelines is used for simulating the pipeline to be repaired.

[0116] Specifically, the present application completes the complete trenchless repair experiment platform design for urban fuel pipelines by inputting the above parameters (pressure level, elbow angle, curvature radius, elbow number, elbow interval, etc.), as shown in Figure 5 .

[0117] S4, using the trenchless repair experiment platform for urban fuel pipelines to determine the feasibility of the pipeline to be repaired and the repair technology;

[0118] The use of the trenchless repair experiment platform for urban fuel pipelines to determine the feasibility of the pipeline to be repaired and the repair technology includes:

[0119] Determination of the passability index of the pipeline to be repaired and the repair technology;

[0120] Determination of the roundness index of the pipeline to be repaired and the repair technology;

[0121] Determination of the air tightness index of the pipeline to be repaired and the repair technology.

[0122] Specifically, the present application uses the experiment platform to determine the feasibility of a certain repair technology, and designs the following three types of indexes including quantitative and qualitative indexes.

[0123] The indexes include but are not limited to:

[0124] I. Passability index

[0125] 1. Speed and traction

[0126] As an optional implementation manner of the embodiment of the present application, the determination of the passability index of the pipeline to be repaired and the repair technology includes:

[0127] Determination of speed and traction;

[0128] Determination of surface scratches;

[0129] wherein the determining the speed and the pulling force comprises:

[0130] whether the speed of the repair material when cutting off the pipe fittings and the elbows is in a preset range;

[0131] whether the pulling force is always less than the maximum allowable pulling force F of the repair material during the pulling process, wherein the maximum allowable pulling force F is calculated by the following formula:

[0132] F = nN1F0

[0133] wherein F is the allowable pulling force, F0 is the average breaking strength of the single fiber in the warp direction, and n is the number of fiber strands in the warp direction.

[0134] In a specific implementation, the speed of the repair material (for example, a fiber-reinforced plastic hose or an HDPE pipe) when cutting off the pipe fittings and the elbows is kept in the range of 3-5 m / min, no obvious speed drop occurs, and the winch works stably without jamming.

[0135] During the whole pulling process, the pulling force is always less than the maximum allowable pulling force F of the repair material, and F should be calculated by the following formula:

[0136] F = nN1F0

[0137] wherein:

[0138] F is the allowable pulling force (N);

[0139] F0 is the average breaking strength of the single fiber in the warp direction, and the unit is Newton (N);

[0140] n is the number of fiber strands in the warp direction;

[0141] N1 is the safety factor, generally taken as 0.6-0.8.

[0142] 2. Surface scratch

[0143] The end glass fiber tape is complete in function, and the tape can have a certain damage but can maintain the U-shaped shape of the inner liner pipe.

[0144] The end of the repair material has no serious scratch, and when the length of the repaired pipeline is L, the length of the end scratch is less than 1‰*L, and the scratch depth does not touch the intermediate woven layer.

[0145] II. Roundness index

[0146] As an optional implementation form of the embodiment of the application, the determining the roundness index of the pipeline to be repaired and the repair technology comprises:

[0147] From the observation hole, observe whether the tape is completely broken, and whether the fitting condition of the straight pipe section and the elbow meets the preset condition.

[0148] In specific implementation, the fitting degree is determined by the following method:

[0149] From the observation hole, observe whether the tape is completely broken, and whether the fitting condition of the straight pipe section and the elbow meets the preset condition.

[0150] Table 1

[0151]

[0152] III. Air tightness index

[0153] As an optional implementation of the embodiment of the application, the determination of the air tightness index of the pipeline to be repaired and the repair technology comprises:

[0154] whether the corrected pressure drop is less than a preset value, wherein the corrected pressure drop is calculated by the following formula:

[0155]

[0156] wherein P' is the corrected pressure drop, H1 and H2 are the pressure gauge readings at the beginning and end of the test, B1 and B2 are the barometer readings at the beginning and end of the test, and t1 and t2 are the pipe medium temperatures at the beginning and end of the test.

[0157] In specific implementation, according to the design pressure PN of the pipeline to be repaired, the air tightness test pressure is 1.15PN, and the pressure maintaining time is 24 hours. If the experimental platform is an overhead pipeline, the pressure is greatly affected by temperature fluctuation, and the test period should be no less than 72 hours to eliminate the influence of day and night temperature difference.

[0158] After sealing the two ends of the pipeline, use an air compressor to slowly pressurize. When the pressure reaches 1.15PN, stop pressurizing. After the pressure in the pipe rises to the tightness test pressure, record after the temperature and pressure are stable. Use the intelligent Beidou air tightness monitoring instrument to monitor the experimental platform, and judge whether the air tightness requirement is met according to the pressure and temperature curve.

[0159] The air tightness determination method is divided into two categories. When the experimental platform is a buried pipeline and there is no prefabricated part and reducing pipe, the (1) type determination method is applicable. When any of the above conditions is not met, the (2) type determination method is applicable.

[0160] (1) According to the provisions of the line standard CJJ33 “Urban Gas Transmission and Distribution Engineering Construction and Acceptance Specification”, when the corrected pressure drop is less than 133Pa, it is qualified. The corrected pressure drop should be determined according to the following formula:

[0161]

[0162] P' - Corrected pressure drop (Pa) ;

[0163] H1, H2 - Pressure gauge readings at the beginning and end of the test (Pa) ;

[0164] B1, B2 - Barometer readings at the beginning and end of the test (Pa) ;

[0165] t1, t2 - Temperature of the medium in the pipe at the beginning and end of the test (℃).

[0166] (2) According to the continuous monitoring data, draw the pressure and temperature curve, when the material expands relatively stably (≥24h), the difference between the pressure value corresponding to the highest temperature of the second day and the pressure value corresponding to the same temperature of the previous day in the monitoring data of the last two days is not less than 133Pa.

[0167] As an optional implementation of the embodiment of the present application, the feasibility determination and selection method of the trenchless repair technology for gas provided by the embodiment of the present application further comprises: forming a qualitative and quantitative evaluation conclusion of whether the trenchless repair technology is feasible, and outputting the evaluation conclusion.

[0168] Specifically, the qualitative and quantitative evaluation conclusion of whether the trenchless repair technology is feasible is formed according to the simulation basis and the test data source.

[0169] The conclusion content can include but is not limited to:

[0170] I. Information statistics of the pipeline to be technically improved

[0171] (1) Design pressure and length of the pipeline to be technically improved

[0172] (2) Number of elbow pipes contained in the pipeline and other pipe conditions

[0173] (3) Angle and radius of curvature of the elbow pipe

[0174] (4) Whether the pipeline contains branch lines

[0175] (5) Original pipe material

[0176] For example: in terms of material, mainly distinguish between steel pipes and PE pipes. At present, the CJJ14 technical regulations are being revised, and after the release, it will be determined which trenchless technologies are used for steel pipes and which technologies can be used for PE pipes.

[0177] Ambient temperature: the gas pipeline is generally buried at a depth of about 1.5-2 meters, and some pipelines may be deeper. The ambient temperature may change, but not much. On the one hand, temperature changes will cause pressure changes; on the other hand, the repair material may expand when the ambient temperature changes, and eventually also cause pressure changes, so the temperature needs to be corrected when the air tightness is quantitatively evaluated.

[0178] Soil parameters have no effect on qualitative and quantitative evaluation.

[0179] The second and third indicators determine whether the pipe section to be improved is suitable for the technology:

[0180] 1. Basic condition index

[0181] (1) Not suitable when the pipe to be repaired has a large area of perforation and local structural strength loss

[0182] (2) Not suitable when there are any structures and devices inside the pipe to be repaired that block the passage of the repair material (such as a water suction cylinder)

[0183] (3) When there are branch lines and connecting pipe fittings, the pipe must be repaired at the branch line or pipe fitting

[0184] 2. Passability index:

[0185] (1) The speed and traction force meet the above determination index

[0186] (2) The material is complete and meets the above determination index

[0187] 3. Performance index:

[0188] (1) The pipe fitting degree meets the above determination index

[0189] (2) The air tightness test meets the above determination index.

[0190] As can be seen, the gas non-excavation repair technology feasibility determination and selection method provided by the embodiments of the present application can determine the feasibility of the gas non-excavation repair technology, save manpower and resources, and improve the efficiency of the use of the gas non-excavation repair technology.

[0191] Figure 6 The structure of the gas non-excavation repair technology feasibility determination and selection device provided by the embodiments of the present application is shown, which applies the above method. Hereinafter, only the structure of the gas non-excavation repair technology feasibility determination and selection device will be simply described, and other matters not covered will be described with reference to the above gas non-excavation repair technology feasibility determination and selection method, see Figure 6 The gas non-excavation repair technology feasibility determination and selection device provided by the embodiments of the present application comprises:

[0192] The establishing module is configured to establish a basic information base, which comprises a pressure level system, a pipe material, a pipe diameter, a bend angle, and a bend radius;

[0193] The determining module is configured to determine, according to environmental information of the pipeline to be repaired and in combination with the basic information base, basic parameters, which comprise a pressure level system of the pipeline to be repaired, a bend angle of the pipeline to be repaired, a bend radius of the pipeline to be repaired, a number of bends of the pipeline to be repaired, a bend interval of the pipeline to be repaired, a number of observation holes, positions of the observation holes, and sizes of the observation holes;

[0194] The generating module is configured to generate, according to the basic parameters, a city fuel pipeline trenchless repair experimental platform, which is used to simulate the pipeline to be repaired;

[0195] The determining module is configured to determine, by using the city fuel pipeline trenchless repair experimental platform, the pipeline to be repaired and the repair technology.

[0196] The determining module determines, by using the city fuel pipeline trenchless repair experimental platform, the pipeline to be repaired and the repair technology in the following manners:

[0197] The determining module determines a pass index of the pipeline to be repaired and the repair technology.

[0198] The determining module determines a roundness index of the pipeline to be repaired and the repair technology.

[0199] The determining module determines a gas tightness index of the pipeline to be repaired and the repair technology.

[0200] As an optional implementation form of the embodiment, the determining module calculates the bend interval of the pipeline to be repaired in the following manner:

[0201]

[0202] Wherein, L is a distance between two adjacent bends, R is a bend radius, n is a total number of bends of the pipeline to be repaired, and t is a safety factor.

[0203] As an optional implementation form of the embodiment, the determining module sets the positions of the observation holes in the following manner:

[0204] An upper detachable part of a pipe is used as an observation hole at a cut-off pipe;

[0205] An observation hole is arranged at a middle part of a bend, and observation holes are arranged at 0 point, 3 point, and 9 point directions of the bend, and at least one bend is simultaneously provided with an inner observation hole and an outer observation hole;

[0206] The observation holes are arranged in the 3 o'clock and 9 o'clock directions of the straight pipe section between the two elbows and the straight pipe section behind the reducing pipe.

[0207] As an optional implementation of the embodiment of the present application, the determining module sets the size of the observation hole in the following manner:

[0208] If it is a straight pipe section or an elbow with R=1.5D, the observation hole is set to have a length L=100-150mm and a width W=(4%-5%)*pi*D;

[0209] If it is an elbow with R=5D, the observation hole is set to have a length L=2*pi*D and a width W=(4%-5%)*pi*D;

[0210] Where D is the diameter of the pipe and R is the curvature radius of the elbow.

[0211] As an optional implementation of the embodiment of the present application, the determining module determines the passability index of the pipe to be repaired and the repair technology in the following manner:

[0212] The speed and the traction force are determined;

[0213] The surface scratch is determined;

[0214] The determination of the speed and the traction force includes:

[0215] Whether the speed of the repair material is in a preset range when the pipe fitting or elbow is cut;

[0216] Whether the traction force is always less than the maximum allowable traction force F of the repair material during the pulling process, where the maximum allowable traction force F is calculated by the following formula:

[0217] F=n*N1*F0

[0218] Where F is the allowable traction force, F0 is the average breaking strength of the longitudinal single fiber, n is the number of longitudinal fiber strands, and N1 is a safety factor.

[0219] As an optional implementation of the embodiment of the present application, the determining module determines the roundness index of the pipe to be repaired and the repair technology in the following manner:

[0220] From the observation hole, it is observed whether the adhesive tape is completely broken and whether the fitting condition of the straight pipe section and the elbow meets a preset condition.

[0221] As an optional implementation of the embodiment of the present application, the determining module determines the air tightness index of the pipe to be repaired and the repair technology in the following manner:

[0222] whether the corrected pressure drop is less than a preset value, wherein the corrected pressure drop is calculated by the following formula:

[0223]

[0224] wherein P' is the corrected pressure drop, H1 and H2 are the pressure gauge readings at the beginning and end of the test, B1 and B2 are the barometer readings at the beginning and end of the test, and t1 and t2 are the temperatures of the medium in the pipe at the beginning and end of the test.

[0225] As an optional implementation of the embodiment of the present application, the feasibility determination and selection of the trenchless repair technology for gas provided by the embodiment of the present application further comprises: an evaluation module configured to form a qualitative and quantitative evaluation conclusion on whether the trenchless repair technology is feasible, and output the evaluation conclusion.

[0226] It can be seen that the device for determining the feasibility of the trenchless repair technology for gas can determine the feasibility of the trenchless repair technology for gas, save manpower and resources, and improve the efficiency of using the trenchless repair technology for gas.

[0227] The above is only an embodiment of the present application and is not intended to limit the present application. The present application can be variously changed and modified by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of the claims of the present application.

Claims

1. A method for determining and selecting a non-excavation repair technology for gas pipelines, characterized in that, include: Establish a basic information database, which includes: pressure rating system, pipe material, pipe diameter, elbow angle and radius of curvature; Based on the environmental data of the pipeline to be repaired and in conjunction with the basic information database, basic parameters are determined. The basic parameters include: the pressure rating of the pipeline to be repaired, the bend angle of the pipeline to be repaired, the radius of curvature of the pipeline to be repaired, the number of bends of the pipeline to be repaired, the bend spacing of the pipeline to be repaired, the number of inspection holes, the location of the inspection holes, and the size of the inspection holes. Based on the aforementioned basic parameters, a trenchless repair experimental platform for urban gas pipelines is generated. This platform is used to simulate the pipeline to be repaired. The feasibility of the pipeline to be repaired and the repair technology was determined using the aforementioned trenchless repair experimental platform for urban gas pipelines. The feasibility assessment of the pipeline to be repaired and the repair technology using the trenchless repair experimental platform for urban gas pipelines includes: The passability indicators of the pipeline to be repaired and the repair technology are determined. The roundness index of the pipeline to be repaired and the repair technology is determined. The airtightness index of the pipeline to be repaired and the repair technology is determined. in: The determination of the passability indicators for the pipeline to be repaired and the repair technology includes: Determine the speed and traction force; Determine the extent of surface scratches; The determination of speed and traction force includes: Whether the speed at which the repair material passes through the cut pipes and elbows is within the preset range; During the pulling process, is the traction force always less than the maximum allowable drag force F of the repair material, wherein the maximum drag force F is calculated by the following formula: F=nN1F0 Where F is the allowable drag force, F0 is the average breaking strength of a single warp fiber, n is the number of warp fiber strands, and N1 is the safety factor.

2. The method according to claim 1, characterized in that, The elbow spacing of the pipeline to be repaired is calculated using the following formula: Where: L is the distance between two adjacent straight pipe sections, R is the radius of curvature of the bend, n is the total number of bends in the pipeline to be repaired, and t is the safety factor.

3. The method according to claim 2, characterized in that, The position of the observation hole is set in the following manner: At the point where the pipe is cut, the detachable part on top of the pipe is used as an observation hole; An observation hole is provided in the middle of the bend, and observation holes are provided at the 0, 3 and 9 o'clock positions of the bend. At least one bend is provided with both inner and outer observation holes. Observation holes are installed at the 3 o'clock and 9 o'clock positions on the straight pipe section between the two bends and the straight pipe section after the reducer.

4. The method according to claim 3, characterized in that, The size of the observation hole is set in the following manner: If it is a straight pipe section or an elbow with R=1.5D, the observation hole is set to a length L=100-150mm and a width W=(4%-5%)*Π*D; If it is an elbow with R=5D, then the observation hole is set to a length L=2*π*D and a width W=(4%-5%)*π*D; Where D is the pipe diameter and R is the radius of curvature of the elbow.

5. The method according to claim 4, characterized in that, The determination of the roundness index of the pipeline to be repaired and the repair technology includes: Observing through the observation hole, the tape completely bursts open, and it is determined whether the fit between the straight pipe section and the elbow meets the preset conditions.

6. The method according to claim 4, characterized in that, The determination of the airtightness index of the pipeline to be repaired and the repair technology includes: Whether the corrected pressure drop is less than a preset value, wherein the corrected pressure drop is calculated by the following formula: Where P' is the corrected pressure drop, H1 and H2 are the pressure gauge readings at the beginning and end of the test, B1 and B2 are the barometer readings at the beginning and end of the test, and t1 and t2 are the temperatures of the medium inside the pipe at the beginning and end of the test.

7. The method according to any one of claims 1 to 6, characterized in that, Also includes: A qualitative and quantitative assessment conclusion on the feasibility of trenchless repair technology is formed, and the assessment conclusion is output.

8. A device for feasibility assessment and selection of non-excavation repair technology for gas, characterized in that, include: A module is established to create a basic information database, which includes: pressure rating, pipe material, pipe diameter, elbow angle, and radius of curvature. The determination module is used to determine basic parameters based on the environmental data of the pipeline to be repaired and the basic information database. The basic parameters include: the pressure rating of the pipeline to be repaired, the bend angle of the pipeline to be repaired, the radius of curvature of the pipeline to be repaired, the number of bends of the pipeline to be repaired, the bend spacing of the pipeline to be repaired, the number of observation holes, the location of the observation holes, and the size of the observation holes. The generation module is used to generate a trenchless repair experimental platform for urban gas pipelines based on the basic parameters. The trenchless repair experimental platform for urban gas pipelines is used to simulate the pipeline to be repaired. The determination module is used to determine the feasibility of the pipeline to be repaired and the repair technology using the trenchless repair experimental platform for urban gas pipelines. The determination module uses the trenchless repair experimental platform for urban gas pipelines to determine the feasibility of the pipeline to be repaired and the repair technology in the following manner: The passability indicators of the pipeline to be repaired and the repair technology are determined. The roundness index of the pipeline to be repaired and the repair technology is determined. The airtightness index of the pipeline to be repaired and the repair technology is determined. in: The determination module determines the passability indicators of the pipeline to be repaired and the repair technology in the following manner: Determine the speed and traction force; Determine the extent of surface scratches; The determination of speed and traction force includes: Whether the speed at which the repair material passes through the cut pipes and elbows is within the preset range; During the pulling process, is the traction force always less than the maximum allowable drag force F of the repair material, wherein the maximum drag force F is calculated by the following formula: F=nN1F0 Where F is the allowable drag force, F0 is the average breaking strength of a single warp fiber, n is the number of warp fiber strands, and N1 is the safety factor.

9. The apparatus according to claim 8, characterized in that, Also includes: The evaluation module is used to generate qualitative and quantitative assessment conclusions on the feasibility of trenchless repair technology and output the assessment conclusions.

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