阅读说明：本技术 一种长输管道内检测器管道弱磁定位方法 (Pipeline weak magnetic positioning method for detector in long-distance pipeline ) 是由 刘思博 陈元 刘艳军 于 2021-03-17 设计创作，主要内容包括：本发明公开一种长输管道内检测器管道弱磁定位方法,包括步骤：S1、搜集分析事故管道的基础资料；S2、对事故管线进行勘察与环境条件分析；S3、测量事故管道的埋深及路由并记录标记；S4、对事故管道进行管段划分；S5、逐段检测事故管道,采集完整的管道弱磁信号；S6、对管道弱磁信号进行管道本体弱磁信号特征分析,得到正常管道空间磁信号特征量；S7、对管道弱磁信号进异常弱磁信号分析,得到管道空间弱磁信号特征量的有效值；S8、根据管道空间弱磁信号特征量的有效值划分正常水平界限；S9、根据正常水平界限区分管道弱磁信号异常区域,确定管道内检测器位置。该方法能精确地实现对埋地输油气铁磁管道内检测器的定位,保证输油气管道的安全运行。(The invention discloses a weak magnetic positioning method for a detector pipeline in a long-distance pipeline, which comprises the following steps: s1, collecting and analyzing basic data of the accident pipeline; s2, performing investigation and environmental condition analysis on the accident pipeline; s3, measuring the buried depth and the route of the accident pipeline and recording marks; s4, dividing the accident pipeline into sections; s5, detecting the accident pipeline section by section, and collecting complete pipeline weak magnetic signals; s6, carrying out pipeline body weak magnetic signal characteristic analysis on the pipeline weak magnetic signals to obtain normal pipeline space magnetic signal characteristic quantities; s7, analyzing the pipeline weak magnetic signals to obtain effective values of the pipeline space weak magnetic signal characteristic quantities; s8, dividing a normal horizontal limit according to the effective value of the pipeline space weak magnetic signal characteristic quantity; and S9, distinguishing the pipeline weak magnetic signal abnormal area according to the normal horizontal limit, and determining the position of the detector in the pipeline. The method can accurately realize the positioning of the detector in the buried oil and gas transmission ferromagnetic pipeline and ensure the safe operation of the oil and gas transmission pipeline.)

1. A weak magnetic positioning method for a detector pipeline in a long-distance pipeline is characterized by comprising the following steps:

s1, collecting and analyzing the basic data of the accident pipeline;

s2, performing investigation and environmental condition analysis on the accident pipeline;

s3, measuring the buried depth and the route of the accident pipeline by using a VLDM-2 buried ferromagnetic pipeline accurate positioning instrument and making records and marks;

s4, performing pipe section division on the accident pipeline according to the mileage mark pile;

s5, detecting the pipeline directly above the accident pipeline section by using a pipeline weak magnetic detector, and collecting complete pipeline weak magnetic signals;

s6, carrying out pipeline body weak magnetic signal characteristic analysis on the pipeline weak magnetic signals acquired in the step S5, and equivalently calculating normal pipeline space magnetic signal characteristic quantities Bx, By and Bz;

s7, carrying out abnormal weak magnetic signal analysis on the pipeline weak magnetic signals acquired in the step S5, and subtracting normal pipeline equivalent space measurement signals Bx, By and Bz from real space weak magnetic signal characteristic quantities Bx1, By1 and Bz1 to obtain effective values Bx, By and Bz of the pipeline space weak magnetic signal characteristic quantities;

s8, dividing the effective value of the pipeline space weak magnetic signal characteristic quantity obtained in the step S7 into a normal horizontal limit;

and S9, distinguishing abnormal areas of the weak magnetic signals of the pipeline by using the normal horizontal boundary divided in the step S8, and determining the accurate position of the blockage of the detector in the pipeline.

2. The method for weak magnetic positioning of a detector pipeline in a long distance pipeline according to claim 1, wherein in step S1, the basic data includes original construction data, midway pipeline change data, in-service repair data and daily maintenance data of the accident pipeline.

3. The method for weakly magnetic positioning of a detector pipeline in a long distance pipeline according to claim 1, wherein in step S3, the target accident pipeline is mapped by using a VLDM-2 buried ferromagnetic pipeline precise locator and an RTK big dipper satellite locator.

4. The method for weak magnetic localization of a detector pipeline in a long distance pipeline according to claim 3, wherein mapping the accident pipeline further comprises labeling ground buildings and feature markers along the path of the detection direction of the accident pipeline, and the error of each identification point from the actual coordinate is less than 1 m.

5. The method for weak magnetic positioning of a detector pipeline in a long distance pipeline according to claim 1, wherein in the step S4, the mileage marking peg is a segment marker of the oil and gas pipeline.

6. The method for positioning weak magnetic field of the detector pipeline in the long distance pipeline according to claim 1, wherein in step S5, the pipeline weak magnetic detector is used to detect segment by segment directly above the route of the accident pipeline, and weak magnetic signals of the accident pipeline are collected.

7. The method for positioning the pipeline flux-weakening of the detector in the long-distance pipeline as claimed in claim 1, wherein in the step S6, the spatial characteristic quantity of the normal pipeline magnetic signal is the average value of the spatial characteristic quantities of the pipeline flux-weakening signal after signal interference is eliminated.

8. The method for positioning weak magnetic of pipeline of detector in long distance pipeline according to claim 1, wherein in said step S7, the effective value of pipeline space magnetic signal is obtained by subtracting normal pipeline equivalent space measurement signal from said real space weak magnetic signal characteristic quantity.

9. The method for weak magnetic localization of detector pipeline in long distance pipeline according to claim 1, wherein in step S8, the normal level limit is obtained from the mean value of effective values of pipeline space magnetic signal.

Technical Field

The invention belongs to the field of detection methods, and particularly relates to a weak magnetic positioning method for a detector pipeline in a long-distance pipeline.

Technical Field

The pipeline magnetic flux leakage internal detection technology is the most widely used contact detection technology for the comprehensive detection of pipelines in the world at present, and the detection process can be divided into conventional pipe cleaning, geometric detection and magnetic flux leakage detection in detail. The detection means has good detection effect on pipeline corrosion, pipeline equivalent wall thickness reduction, cracks and growth caused by stress concentration. The pipeline magnetic leakage internal detection is realized by using the fluid internal pressure in the pipeline to emit an internal detector which can acquire and record pipeline information in real time to operate in the pipeline under the condition of not influencing the transportation of pipeline media, and the pipeline magnetic leakage internal detection is also called intelligent pigging.

The following takes the detection work in the cruel single-line crude oil conveying pipeline as an example, the internal detection flow is introduced in detail, and the detection work in the magnetic leakage of the crude oil pipeline has the following three stages:

1) the pigging is usually accomplished with the pig such as software pig, leather cup pig, magnetic force pig and calimetry, and the purpose is to clear away the impurity of pipeline inner wall, water and sulfate radical reducing bacteria etc. slows down the corruption of pipeline inner wall on the one hand, and on the other hand reduces pipeline resistance, preliminary aassessment geometry detector can pass through smoothly.

2) Geometric measurements, in addition to the above-mentioned deformations and ovality of the inspection duct, are secondly used to evaluate whether the internal detector can pass through successfully.

3) And magnetic flux leakage detection mainly detects corrosion defects and weld defects of the long-distance pipeline, oil stealing holes of the oil stealing valve and the like.

In most practical oil and gas station fields, the pipeline pigs and the inner detectors are sent out in sequence for saving time and economic cost, especially for a crude oil pipeline, the amount of viscous material attached to the inner wall of the pipeline is large, when the resistance of the pipeline wall attachments to the pipeline pigs is larger than the thrust of pipeline fluid to the pipeline pigs, the pipeline pigs stop moving, and then the inner detectors launched later can also be retained due to the clamping balls of the pipeline pigs. Secondly, due to the long-term action of the geographical environment and the internal operating conditions of the pipeline, the buried ferromagnetic pipeline has defects at the growing position inevitably, and particularly, the phenomenon that an internal detector cannot pass through the large deformation of the pipeline caused by the stress concentration influence also occurs. In addition, due to the influence of complicated geographical conditions or later-stage pipeline route change in the construction period, the design radian of the pipeline elbow is difficult to pass through the inner detector of a large-size pipeline cleaner, and the retention of the inner detection of magnetic flux leakage can be caused. Although with the development of science and technology, the inner detector is equipped with a signal transmitting device, if the inner detector is not found to be clamped in the pipe in time, the position of the inner detector is lost when the electric quantity of the signal transmitting device of the inner detector is exhausted along with the time, the safe operation of the oil and gas pipeline and the normal operation of the inner detection work are seriously influenced, and therefore, the method for positioning the inner detector of the long-distance pipeline has important practical significance.

Disclosure of Invention

Aiming at the problems, the invention provides a weak magnetic positioning method for a pipeline of a long-distance pipeline internal detector, aiming at accurately positioning the internal detector for an accident pipeline of a corresponding internal detection pipe clamp; the invention fully utilizes the VLDM-2 buried ferromagnetic pipeline precise positioning instrument, the RTK and the pipeline weak magnetic detector, precisely measures the route and the buried depth of the accident pipeline, accurately correlates the mileage and the coordinates of the pipeline, detects section by section, further precisely analyzes the detention position of the detector in the pipeline, facilitates the pipeline repair and the extraction of the inner detector, improves the working efficiency and saves the economic cost. The invention adopts the following technical scheme:

a weak magnetic positioning method for a detector pipeline in a long-distance pipeline is characterized by comprising the following steps:

s1, collecting and analyzing the basic data of the accident pipeline;

s2, performing investigation and environmental condition analysis on the accident pipeline;

s3, measuring the buried depth and the route of the accident pipeline by using a VLDM-2 buried ferromagnetic pipeline accurate positioning instrument and making records and marks;

s4, performing pipe section division on the accident pipeline according to the mileage mark pile;

s5, detecting the pipeline directly above the accident pipeline section by using a pipeline weak magnetic detector, and collecting complete pipeline weak magnetic signals;

s6, carrying out pipeline body weak magnetic signal characteristic analysis on the pipeline weak magnetic signals acquired in the step S5, and equivalently calculating normal pipeline space magnetic signal characteristic quantities Bx, By and Bz;

s7, carrying out abnormal weak magnetic signal analysis on the pipeline weak magnetic signals acquired in the step S5, and subtracting normal pipeline equivalent space measurement signals Bx, By and Bz from real space weak magnetic signal characteristic quantities Bx1, By1 and Bz1 to obtain effective values Bx, By and Bz of the pipeline space weak magnetic signal characteristic quantities;

s8, dividing the effective value of the pipeline space weak magnetic signal characteristic quantity obtained in the step S7 into a normal horizontal limit;

and S9, distinguishing abnormal areas of the weak magnetic signals of the pipeline by using the normal horizontal boundary divided in the step S8, and determining the accurate position of the blockage of the detector in the pipeline.

Preferably, in step S1, the basic data of the accident pipe includes original construction data, intermediate management data, in-service maintenance data, and daily maintenance data of the pipe.

Preferably, in step S3, the VLDM-2 buried ferromagnetic pipeline accurate positioning instrument and the RTK beidou satellite positioning instrument are used to survey and draw the target accident pipeline.

Preferably, in step S3, the step of performing on the accident pipe further includes labeling the ground buildings and the feature markers along the path of the detection direction of the accident pipe, and the error between each identification point and the actual coordinate is less than 1 m.

Preferably, in step S4, the mileage marking peg is a segment marker of the oil and gas pipeline.

Preferably, in step S5, a pipeline weak magnetic detector is used to detect the pipeline weak magnetic directly above the route of the accident pipeline, and weak magnetic signals of the accident pipeline are collected.

Preferably, in step S6, the normal pipeline spatial magnetic signal characteristic quantity is an average value of spatial characteristic quantities of the pipeline weak magnetic signal after signal interference is eliminated.

Preferably, in step S7, the effective value of the pipeline spatial magnetic signal is obtained by subtracting the normal pipeline equivalent spatial measurement signal from the real space weak magnetic signal characteristic quantity.

Preferably, in step S8, the normal level limit is obtained from an average value of effective values of the magnetic signal in the pipe space.

The invention has the beneficial effects that:

1. the method for positioning the pipeline weak magnetism of the long-distance pipeline internal detector fully utilizes the precision performance of the pipeline weak magnetism detector, overcomes the difficulty of searching the internal detector by blind excavation, and saves time and economic cost.

2. The method for positioning the detector in the buried oil and gas ferromagnetic pipeline can arrange the weak magnetic signals above the pipeline into a pipeline weak magnetic information base, so that the stress level information of the whole oil and gas pipeline is clear, weak magnetic signals different from normal pipe sections can appear in the place where the inner detector is detained, and the position information of the detector in the pipeline magnetic leakage can be conveniently locked.

3. The method for positioning the detector in the buried oil and gas transmission ferromagnetic pipeline fully utilizes the pipeline weak magnetic signal acquired by the pipeline weak magnetic detector and the coordinate system of the pipeline, not only can accurately position the inner detector, but also can correct the routing information of the pipeline changed due to environmental factors, and provides reliable basis for the integrity management and risk assessment of the oil and gas transmission pipeline.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings of the embodiments are briefly introduced below. It is to be understood that the drawings in the following description are directed to only some embodiments of the invention and are not intended as a definition of the limits of the invention.

FIG. 1 is a schematic diagram of the positioning and detecting process of the detector in the buried oil and gas transmission ferromagnetic pipeline;

FIG. 2 is a schematic diagram of the weak magnetic detection of a ferromagnetic pipeline;

fig. 3 is a schematic diagram of the positioning of a detector in a pipe section for detecting an accident in oil and gas transmission.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawings of the embodiments of the present invention. It is to be understood that the described examples are exemplary of some, but not all embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the invention without any inventive step, are within the scope of protection of the invention.

Unless defined otherwise, technical or scientific terms used in the present disclosure should have the ordinary meaning as understood by those of ordinary skill in the art to which the present invention belongs. The use of the word "comprise" or "comprises", and the like, in the context of this application, is intended to mean that the elements or items listed before that word, in addition to those listed after that word, do not exclude other elements or items. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

The invention is further illustrated with reference to the following figures and examples.

Referring to the flowchart in fig. 1, the method for positioning the weak magnetism of the detector pipeline in the long-distance pipeline according to the embodiment includes the following steps:

s1, collecting and analyzing the basic data of the accident pipeline;

according to the GB/T35090-2018 nondestructive testing pipeline weak magnetic detection technology, pipeline basic data collection is required before a weak magnetic detector is used. The basic data comprises the name of the pipeline, an operation unit, the input operation time, the length of the pipeline, the wall thickness of the pipeline, the outer diameter of the pipeline, the operation pressure, the design pressure, the material of the pipeline, the buried depth range of the pipeline, a conveying medium, an anticorrosive coating, the recent detection condition, the maintenance condition of the pipeline and other related information, and the initial analysis is carried out on the working condition and the operation and maintenance of the pipeline.

S2, performing investigation and environmental condition analysis on the accident pipeline;

the oil and gas transmission pipeline is often laid in a place with complex environmental conditions, and before detection, a series of environmental conditions such as traffic conditions, weather hydrology, current land utilization situation, regional geological structure, new structure movement and earthquake general, landform and landform, soil resistivity, water and soil corrosivity, road crossing, ditch crossing and the like in a pipeline region need to be recorded, so that interference identification can be conveniently carried out in a data post-processing stage.

S3, measuring the buried depth and the route of the accident pipeline by using a VLDM-2 buried ferromagnetic pipeline accurate positioning instrument and making records and marks;

the underground pipeline detector adopts the working principle that an electromagnetic method is adopted to detect the underground pipeline, a transmitter applies electromagnetic excitation to a medium in a metal pipeline or a pipeline, pipeline current is generated in the metal pipeline, and a secondary magnetic field is generated around the pipeline; the secondary magnetic field of the pipeline is measured at the ground through the receiver, so that the route and the burial depth of the pipeline are accurately determined. In the process of detecting the pipeline path, the anode of a signal emitter is connected with a cathode protection pile of a buried ferromagnetic pipeline, an electric signal is transmitted to the oil and gas transmission ferromagnetic pipeline through the cathode protection pile, the cathode of the signal emitter is grounded, so that a closed loop is formed among an electric signal emitting end, the metal pipeline and the ground, and a signal receiving and analyzing device is used for detecting a magnetic field generated by a pipeline; after the signal transmitting end is connected, a power supply of a receiver is started, proper frequency and gain display is selected, a trough mode is used for buried position and route detection, after the position and the route direction of a pipeline are determined, a crest mode is selected to determine the buried depth of the pipeline, the found route direction of the pipeline is marked, and a detected pipe section is recorded. The detection data also comprises the label of the ground building and the characteristic marker along the detection direction path of the pipe section, and the error between each marker point and the actual coordinate is less than 1.0 m.

S4, performing pipe section division on the accident pipeline according to the mileage mark pile;

the mileage mark pile is a mark connected with the surface of the pipeline, and compared with other warning boards, elbow prompts and simple marks, the position of the mileage mark pile is more accurate, and complete information of the detected pipeline, including the pipeline name, the pipeline mileage, the pile number and the like, is marked on the mileage mark pile. In addition, the pipeline mileage mark piles are generally arranged at intervals of 1km, so that data analysis of subsequent weak magnetic detection is facilitated.

S5, detecting the pipeline directly above the accident pipeline section by using a pipeline weak magnetic detector, and collecting complete pipeline weak magnetic signals;

as shown in fig. 2, the principle of the pipeline weak magnetic detection technology is based on the inverse magnetostriction effect of the ferromagnetic material and the metal magnetic memory effect. When the ferromagnetic material is excited by an external magnetic field, the magnetic domains in the material are reoriented, so that the distribution of the magnetic induction lines of the material is abnormal, which is called a magnetostrictive effect. Similarly, when external stress acts on a ferromagnetic material, the external stress can be regarded as an excitation field, and the magnetic domain structure inside the material is correspondingly changed to generate a corresponding leakage magnetic field, which is called an inverse magnetostriction effect. When an external excitation field (stress field or magnetic field) is removed, the orientation of a magnetic domain structure in the material is irreversible, the generated leakage magnetic field cannot be reduced to zero, the process is called a metal magnetic memory effect, the normal component of a magnetic signal at a stress abnormal position has a zero crossing point, and the tangential component has a maximum value. When the detector is detained inside the pipeline in leaking magnetism, the pipeline receives the extrusion on the one hand and can produce weak magnetic signal, and the weak magnetic signal of this position of on the other hand is the superimposed state of the weak magnetic signal of pipeline body and the weak magnetic signal of interior detector, and the possible position of detaining of detector in the pipeline leakage magnetism is tentatively confirmed to the unusual magnetic signal characteristic information of preliminary stress of accessible.

S6, carrying out pipeline body weak magnetic signal characteristic analysis on the pipeline weak magnetic signals collected in the step S5, eliminating interference, and then equivalently calculating normal pipeline space magnetic signal characteristic quantities Bx, By and Bz By using a mean value;

s7, carrying out abnormal weak magnetic signal analysis on the pipeline weak magnetic signals acquired in the step S5, and subtracting normal pipeline equivalent space measurement signals Bx, By and Bz from real space weak magnetic signal characteristic quantities Bx1, By1 and Bz1 to obtain effective values Bx, By and Bz of the pipeline space weak magnetic signal characteristic quantities;

s8, dividing the effective value of the pipeline space weak magnetic signal characteristic quantity obtained in the step S7 into a normal horizontal limit, wherein the horizontal limit is the mean value of the effective values;

and S9, distinguishing abnormal areas of the weak magnetic signals of the pipeline by using the normal horizontal boundary divided in the step S8, and determining the accurate position of the blockage of the detector in the pipeline.

As shown in fig. 3, when the effective value of the pipeline weak magnetic signal exceeds the horizontal limit value, the detention position of the detector in the pipeline leakage magnetic can be quickly judged.

After the method is adopted, compared with the positioning of the detector in the buried long-distance pipeline, the method is used for positioning the detector in the buried long-distance pipeline based on the practical application of engineering, the target accident pipeline is processed in a segmented mode according to the mileage mark pile, and the distance can be increased or reduced according to the practical situation; compared with a pipeline or an elbow with a complex ground environment, the length of a detection area can be obviously reduced; the method has better accurate guarantee for excavation and recovery of the detector in the field oil and gas pipeline.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.