Photoelectric sensor-based mileage measurement device and method for detector within pipeline

Abstract

Apparatus for measuring the internal length of a pipeline comprising a photoelectric sensor-based mileage measurement device for a detector within a pipeline, including an inner detector 1, three mile

Description

[0002] The application relates to the technical field of pipeline internal measurement, and in 10 particular to a photoelectric sensor-based mileage measurement device for a detector within । pipeline. * BACKGROUND OF THE INVENTION

[0003] Gas pipelines are widely used in transportation of gases such as natural gas. For the transportation of gas, it is very important to measure the actual transportation distance thereof. 15 However, lengths of inner and outer walls of the gas pipeline are not the same. Especially at corners of a gas pipeline, the length difference between the inner wall and the outer wall of the gas pipeline will become larger, while the actual transportation distance of the gas transported in the gas pipeline is the length of the inner wall of the gas pipeline. A conventional external length measurement for a gas pipeline cannot accurately provide the actual condition of the inner wall 20 of the pipeline, therefore the actual mileage of the gas pipeline needs to be measured inside / within the gas pipeline.

[0004] Currently, mechanical mileage wheels are used to measure the mileage of gas pipelines. Generally, three mileage wheels are co-operatively used in a detector to measure the mileage. Wheel bodies are pressed against the inner wall of the pipeline via a support structure and springs, 25 and sufficient friction is provided. When the inner detector moves within the pipeline, the mileage wheels will rotate under the action of friction. A rotor magnetic pole and a stator rotation displacement encoder are provided inside the mileage wheel. When the mileage wheel rotates, displacement pulses will be generated, and an electronic system will count the displacement pulses, so as to measure the internal mileage.

[0005] Although such a technology may obtain an internal mileage of gas pipelines, there are 5 welds at the welding regions of the pipeline, and these welds will cause mileage wheels to suffer from a problem of lifting-off, which has a great impact on the accuracy of the internal mileage measurement. A conventional solution to solve this weld-beads problem is generally to obtain original design drawings for the gas pipeline, and scale the impact of all welds in the gas pipeline to be detected on the internal mileage down to a fixed factor value, so as to cancel off the impact 10 of the welds on the internal mileage. However, mechanical mileage wheels are very likely to slip at welds, which makes it impractical to simply use a fixed weld influence factor value to cancel off the impact on the internal mileage of the gas pipeline. SUMMARY OF THE INVENTION CM QQ

[0006] This application is based on solving the problem of inaccurate internal measurement of 5 pipelines in the prior art, and provides a photoelectric sensor-based mileage measurement device 1— for a detector within pipeline.

[0007] In a first aspect, this application provides a photoelectric sensor-based mileage measurement device for a detector within pipeline. The mileage measurement device includes:

[0008] an inner detector; 20

[0009] three mileage wheel support arms which are uniformly distributed in a circumferential direction of the inner detector, wherein one end of each mileage wheel support arm is hinged with the inner detector, and the other end of each mileage wheel support arm is provided with a mileage wheel; when the mileage measurement device moves within the pipeline to be detected, the mileage wheels always abut against an inner wall of the pipeline to be detected; 25

[0010] angular displacement sensors provided at respective hinged positions of the mileage wheel support arms with the inner detector, wherein the angular displacement sensors are electrically coupled to the inner detector for detecting changes in angular displacement between the mileage wheel support arms and the inner detector, and generate weld signals that are fed back to the inner detector;

[0011] photoelectric sensors provided in front of respective mileage wheels in a travelling direction, wherein the photoelectric sensors are electrically coupled to the inner detector for obtaining circumferential images of the inner wall of the pipeline to be detected, wherein the circumferential images are fed it back to the inner detector; 5

[0012] wherein the inner detector is configured to calculate an actual mileage traveled by the mileage measurement device in the pipeline to be detected based on the circumferential images and the weld signals.

[0013] In some embodiments, each mileage wheel support arm includes a first mileage wheel support arm and a second mileage wheel support arm; 10

[0014] one end of the first mileage wheel support arm is hinged to the inner detector at a side of away from the inner wall of the pipeline to be detected, with several limiting springs being provided at connection between the first mileage wheel support arm and the inner detector;

[0015] the other end of the first mileage wheel support arm is detachably connected with one । end or the second mileage wheel support arm, with the photoelectric sensor being provided at the 15 other end of the second mileage wheel support arm; ►

[0016] the mileage wheel is pivotally connected between the first mileage wheel support arm ■ and the second mileage wheel support arm. ’

[0017] In some embodiments, a first device connection surface and a second device connection surface are respectively provided at two sides of the mileage wheel in the travelling direction, 20 wherein the first mileage wheel support arm is hinged to the mileage wheel on the first device connection surface, and the second mileage wheel support arm is coupled to the mileage wheel on the second device connection surface;

[0018] wherein the photoelectric sensor includes:

[0019] a sensor carrier coupled with the second mileage wheel support arm; and 25

[0020] a photoelectric sensing unit arranged on one side of the sensor carrier that is away from the mileage wheel.

[0021] In some embodiments, an X-shaped snap-in slot is provided at one end of the first mileage wheel arm that is away from the inner detector;

[0022] an X-shaped snap-in post is provided at the connection between the second mileage 30 wheel support arm and the first mileage wheel support arm; and

[0023] the X-shaped snap-in post matches with the X-shaped clamping slot;

[0024] wherein the mileage measurement device further includes:

[0025] covering caps respectively snapped on both of the first device connection surface and the second device connection surface, wherein the covering cap includes a first covering cap that 5 is snapped on one side of the first device connection surface and a second covering cap that is snapped on one side of the second device connection surface; and

[0026] a spring provided between the first mileage wheel support arm and the second mileage wheel support arm.

[0027] In a second aspect, this application provides a photoelectric sensor-based mileage 10 measurement method for a detector within pipeline. The mileage measurement method includes:

[0028] obtaining circumferential images inside the pipeline to be detected;

[0029] obtaining multiple changes in the angular displacement between the first mileage wheel arm and the inner detector when the mileage detection device is running in the pipeline to be I de,ec,ed; 15

[0030] determining whether all changes in the angular displacement comply with an angular J displacement change rule for a weld;

[0031] recording all changes in the angular displacement that comply with the angular displacement change rule for a weld and generating weld signals; and

[0032] calculating the actual mileage travelled by the mileage measurement device in the 20 pipeline to be detected according to the circumferential images and weld signals.

[0033] In some embodiments, after the recording all changes in the angular displacement that comply with the angular displacement change rule for a weld and generating weld signals, the mileage measurement method further includes:

[0034] determining, for each weld signal, whether the change in the angular displacement 25 complies with the image change rule for a weld according to circumferential images;

[0035] extracting, from weld signals, all angular displacement changes that comply with the image change rule for a weld;

[0036] recording all angular displacement changes that comply with the image change rule for a weld; 30

[0037] generating target weld information according to the angular displacement changes that comply with the image change rule for a weld;

[0038] recording, for weld signals, all angular displacement changes that do not comply with the image change rule for a weld; and

[0039] generating pipeline corrosion information according to the angular displacement 5 changes that do not comply with the image change rule for a weld.

[0040] In some embodiments, the calculating the actual mileage travelled by the mileage measurement device in the pipeline to be detected according to the circumferential images and weld signals includes:

[0041] calculating corrosion influencing factors according to the pipeline corrosion 10 information;

[0042] calculating a basic mileage travelled by the mileage measurement device in the pipeline to be detected according to the target weld information and the circumferential images;

[0043] calculating an actual mileage travelled by the mileage measurement device in the । pipeline to be detected according to the corrosion influencing factors and the basic mileage. 15

[0044] In some embodiments, the change in the angular displacement includes a first half of 1 the change and a second half of the change, the angular displacement change rule for a weld is ■ that the angle first becomes smaller and then becomes larger; wherein the determining whether all changes in the angular displacement comply with an angular displacement change rule for a weld includes: 20

[0045] determining whether the first half of the change indicates a decrease of the angle;

[0046] if not, recording the change in the angular displacement as pipeline fouling information;

[0047] if yes, determining whether the second half of the change indicates an increasement of the angle;

[0048] if not, recording the change in the angular displacement as pipeline fouling information; 25

[0049] if yes, determining that all the changes in the angular displacement comply with the angular displacement change rule for a weld.

[0050] In some embodiments, the determining, for each weld signal, whether the change in the angular displacement complies with the image change rule for a weld according to circumferential images includes: 30

[0051] obtaining an image position for each assumptive weld according to the weld signals and the circumferential images;

[0052] determining whether all photoelectric sensors in the mileage measurement device detect changes in pixel grayscale at the image position of the assumptive weld;

[0053] if not, recording the angular displacement changes corresponding to said image position 5 of the assumptive weld as pipeline fouling information;

[0054] if yes, determining that for the angular displacement changes corresponding to said image position of the assumptive weld, the image change rule for a weld has been complied with.

[0055] In some embodiments, the mileage measurement method further includes:

[0056] obtain all pipeline fouling information; 10

[0057] generating pipe fouling locations according to each pipe fouling information and the circumferential images.

[0058] This application provides a photoelectric sensor-based mileage measurement device and method for a detector within pipeline, which solves the problems of inaccurate mileage measurement caused by mileage wheel slippage and mechanical failure in the mileage measurement method, and adds weld position information to original mileage record, internal detection mileage condition can be accurately recorded in combination with pipeline construction drawings, and subsequent defect positioning and construction are facilitated. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to explain the technical solutions according to this application more clearly, 20 drawings used in the embodiments will be briefly introduced below. Obviously, for those of ordinary skill in the art, additional drawings can be obtained from these drawings without creative efforts.

[0060] Fig 1 is a front view of a photoelectric sensor-based mileage measurement device for a detector within pipeline according to this application; 25

[0061] Fig 2 is a side view of A in Fig. 1;

[0062] Fig. 3 is a front view of a photoelectric sensor in a photoelectric sensor-based mileage measurement device for a detector within pipeline according to this application;

[0063] Fig 4 is an exploded view illustrating the structure of mileage wheel support arms in the photoelectric sensor-based mileage measurement device for a detector within pipeline according to this application;

[0064] Fig. 5 is a side view of a second mileage wheel support arm in the photoelectric sensorbased mileage measurement device for a detector within pipeline according to this application;

[0065] Fig. 6 is a side view of a mileage wheel in the photoelectric sensor-based mileage 5 measurement device for a detector within pipeline according to this application;

[0066] Fig. 7 is a side view illustrating a mileage wheel and covering caps of the photoelectric sensor-based mileage measurement device for a detector within pipeline according to this application;

[0067] Fig. 8 is a flow chart of a photoelectric sensor-based mileage measurement method for 10 a detector within pipeline according to this application;

[0068] Fig. 9 is a flow chart for generating weld information in the photoelectric sensor-based mileage measurement method for a detector within pipeline according to this application;

[0069] Fig. 10 is a flow chart for calculating the actual mileage of the photoelectric sensor- ' . I-. . . „ ...... .. ..... । based mileage measurement device for a detector within pipeline according to this application; 15

[0070] Fig. 11 is a flow chart for determining whether all changes in the angular displacement I comply with the changes in the angular displacement of the welds in the photoelectric sensor- ■ based mileage measurement method for a detector within pipeline according to this application;

[0071] Fig 12 is a flowchart for determining whether each of the changes in the angular displacement in the weld information complies with the changes in weld images in the 20 photoelectric sensor-based mileage measurement method for a detector within pipeline according to this application;

[0072] Fig 13 is a flow chart for obtaining fouling locations in the photoelectric sensor-based mileage measurement method for a detector within pipeline according to this application. DETAILED DESCRIPTION OF THE EMBODIMENTS 25

[0073] The technical solution in the embodiments of the invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the invention. Obviously, the described embodiments merely illustrate some of the embodiments of the invention, not all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the invention without creative efforts will fall within the scope of protection of the invention.

[0074] Referring to Figs. 1 and 2, it can be seen that this embodiment provides an photoelectric sensor-based mileage measurement device for a detector within pipeline, which includes:

[0075] an inner detector 1, which is used to coordinate and calculate the relevant data obtained 5 from the mileage measurement device, and finally obtain the actual mileage of the mileage measurement device running in the pipeline to be detected;

[0076] three mileage wheel support arms 2, which are evenly distributed along the circumferential direction of the inner detector 1; for each mileage wheel support arm 2, one end thereof is hinged to the inner detector 1, and the other end is provided with a mileage wheel 3; 10 when the mileage measurement device moves inside the pipeline to be detected, the mileage wheels 3 are always abutting against the inner wall of the pipeline to be detected. These mileage wheel support arms 2 function to support respective mileage wheels 3 in this embodiment; meanwhile, since one end of the mileage wheel support arm 2 is hinged to the inner detector 1, । the mileage wheel support arm 2 is enabled to pivot within a certain range to accommodate for a 15 full-size pipeline inspection; 1

[0077] an angular displacement sensor 4, which is provided at the hinged position of the ■ mileage wheel support arm 2 with the inner detector 1; the angular displacement sensor 4 is electrically coupled to the inner detector 1, is used to detect a change in the angular displacement between the mileage wheel support arms 2 and the inner detector 1, and generates weld 20 information which is fed back to the inner detector 1; in this embodiment, the angular displacement sensor 4 is used to obtain the change in the angular displacement between the mileage wheel support arms 2 and the inner detector 1, where the change in this angular displacement represents the change in the angle between the mileage wheel support arm 2 and the inner detector 1; by detecting the change in the angular displacement, accurate positions of welds 25 in the pipeline to be detected may be obtained, and thereby the impact of the welds on the actual mileage travelled by the mileage measurement device may be eliminated;

[0078] a photoelectric sensor 5 which is arranged in front of the mileage wheel 3 in the traveling direction; the photoelectric sensor 5 is electrically coupled to the inner detector 1, and is used to obtain the circumferential image of the inner wall of the pipeline to be detected and feed this 30 circumferential image back to the inner detector 1; in this embodiment, the photoelectric sensor 5 is used to obtain a circumferential image of the inner wall of the pipeline to be detected, and the circumferential image is used to accurately describe a running trajectory image generated when the mileage measurement device is running within the pipeline to be detected.

[0079] The inner detector 1 is configured to calculate the actual mileage of the mileage 5 measurement device running in the pipeline to be detected according to the circumferential image and the weld information. In this embodiment, the inner detector 1 calculates the actual mileage of the mileage measurement device running in the pipeline to be detected by using the circumferential image and weld information, thus avoids a problem of measurement inaccuracies caused by slippage by means of the detected circumferential images, and also obtains actual 10 condition of the welds by means of the weld information, so as to cancel off the impact of the welds on the actual mileage run-through by the mileage measurement device. By making a cooperative use of the circumferential images and the weld information, the accuracy and reliability of the mileage measurement inside pipelines may be significantly improved. ।

[0080] It should be noted that in Fig. 2, the protruding part in the traveling direction of the 15 mileage measurement device represents a weld. ►

[0081] Further, in some embodiments, the mileage wheel support arms 2 includes a first ■ mileage wheel support arm 21 and a second mileage wheel support arm 22. One end of the first mileage wheel support arm 21 is hinged on a side of the inner detector 1 away from the inner wall of the pipeline to be detected, and several limiting springs are provided at the connection between 20 the first mileage wheel support arm 21 and the inner detector 1. By articulating the first mileage wheel support arm 21 with the inner detector 1 so as to obtain the angular displacement of the mileage wheel support arms 2, this embodiment also considers the problem of “free swinging” of the first mileage wheel support arm 21. Several limiting springs are also provided at the connection between the first mileage wheel support arm 21 and the inner detector 1. Through the 25 limiting springs, during the absence of an external force, the first mileage wheel support arm 21 is restrained in a stationary state. When there is an external force, the first mileage wheel support arm 21 rotates towards the second mileage wheel support arm 22. When the external force is removed, the first mileage wheel support arm 21 can in turn be restored into the initial stationary state. The other end of the first mileage wheel support arm 21 is detachably connected to one end 30 of the second mileage wheel support arm 22. The photoelectric sensor 5 is arranged on the other end of the second mileage wheel support arm 22. The mileage wheel 3 is pivotally connected between the first mileage wheel support arm 21 and the second mileage wheel support arm 22. By connecting the other end of the first mileage wheel support arm 21 to the second mileage wheel support arm 22 in a detachable way, maintenance and replacement of the mileage wheel 3 5 may be facilitated, and utilization efficiency of the parts of the mileage measurement device may be optimized.

[0082] It should be noted that the second mileage wheel support arm 22 in this embodiment not only plays the role of mounting the photoelectric sensor 5, but also plays the role of stabilizing the photoelectric sensor 5 to a certain extent. The implementation structure specifically for 10 stabilizing the photoelectric sensor 5 can be seen in Fig. 4, 5, 6 and 7. The specific implementation structure thereof is:

[0083] an X-shaped snap-in slot 211 is provided at one end of the first mileage wheel support arm 21 away from the inner detector 1, and an X-shaped snap-in post 221 is provided on the । second mileage wheel support arm 22 at the connection with the first mileage wheel support arm 15 21. The snap-in post 221 is adapted to the X-shaped snap-in slot 211. By utilizing a nested fixation J between the X-shaped snap-in post 221 and the X-shaped snap-in slot 211, the second mileage ■ wheel support arm 22 is prevented from free rotating, thereby providing stability. '

[0084] The specific implementation structure further includes: a covering cap 6 that is snapped-engaged with a first device connection surface and a second 20 device connection surface of the mileage wheel 3, respectively. The covering cap 6 includes a first covering cap 61 that is snapped into one side of the first device connection surface and a second covering cap 62 that is snapped into one side of the second device connection surface; and a spring 7 that provided between the first mileage wheel support arm 21 and the second mileage wheel support arm 22. By means of the spring 7, a problem of a sudden rebound of the 25 second mileage wheel support arm 22 when the first mileage wheel support arm 21 rotates to a maximum extent with respect to the second mileage wheel support arm 22 and the rotation angle decreases abruptly may be avoided; meanwhile, the connection between the mileage wheel 3, the first mileage wheel support arm 21 and the first mileage wheel support arm 21 may be respectively secured by the covering caps 6, which further stabilizes the photoelectric sensor 5; besides, the 30 provision of the covering cap 6 can also prevent dust from entering a rotation axle of the mileage wheel 3, thereby improving running smoothness of the mileage measurement device.

[0085] Specifically, a implementation of the photoelectric sensor 5 for obtaining a circumferential image of the inner wall of the pipeline to be detected can be seen in Fig. 3. The specific implementation is: 5

[0086] two sides of the mileage wheel 3 with respect to the traveling direction respectively have a first device connection surface and a second device connection surface; the first mileage wheel support arm 21 is hinged with the mileage wheel 3 along the first device connection surface, and the second mileage wheel support arm 22 is hinged with the mileage wheel 3 along the second device connection surface; the photoelectric sensor 5 includes a sensor carrier 51 connected to 10 the second mileage wheel support arm 22 and a photoelectric sensing unit 52 arranged on a side of the sensor carrier 51 away from the mileage wheel 3.

[0087] In this embodiment, photoelectric sensing units 52 are arranged in three directions respectively to obtain circumferential images of the inner wall of the detection pipeline; the j difference from the prior art is that in the prior art, even if the circumferential images of the inner 15 wall of the pipeline to be detected can be obtained, due to the influence of the welds, it can only J function as a single sensor, while this embodiment solves the weld problem via circumferential ■ images, and mileage detection of the pipeline to be detected is achieved via the weld information and the circumferential images jointly, avoiding the problem of inaccurate detection caused by welds in the prior art. 20

[0088] It should be noted that the width and length of the sensor carrier 51 in this embodiment can be changed according to requirements, that is, the sensor of the photoelectric sensing unit 52 on the sensor carrier 51 and the inner wall of the pipeline to be detected may be respectively arranged via a close fit and or with a certain distance therebetween. In case of a close fit, the working principle of the photoelectric sensing unit 52 may be referred to as a “mouse optical 25 sensor”, and in case of a certain distance, the photoelectric sensing unit 52 may operate in a normal / conventional image acquisition method.

[0089] Referring toFigs 7, 8, 9, 10 and 11, it can be seen that this embodiment also provides a photoelectric sensor-based mileage measurement method for a detector within pipeline. The mileage measurement method includes: 30

[0090] SI00, obtaining circumferential images inside the pipeline to be detected; said procedure is performed via a photoelectric sensor, specifically via three photoelectric sensing units respectively provided in the photoelectric sensor;

[0091] S200, obtaining changes in the angular displacement between the first mileage wheel support arm and the inner detector when the mileage detection device is running in the pipeline 5 to be detected; said procedure is performed via an angular displacement sensor. It should be noted that, the changes in the angular displacement obtained by the angular displacement sensor are the changes in the angle between the first mileage wheel support arm in the mileage wheel support arms and the inner detector;

[0092] S300, for all changes in the angular displacement, determining whether they comply 10 with the angular displacement change rule for a weld; said procedure is performed by the inner detector, where the change in the angular displacement includes two halves, i.e., a first half of the change and a second half of the change; the angular displacement of the weld is changed in such a way that the angle first becomes smaller and then becomes larger. The specific steps are: j

[0093] S301, determining whether the first half of the change indicates a decrease of the angle; 15

[0094] S304, if not, then the change in the angular displacement is recorded as pipeline fouling J information;

[0095] S302, if yes, then determining whether the second half of the change indicates an increasement of the angle;

[0096] S304, if not, then the change in the angular displacement is recorded as pipeline fouling 20 information;

[0097] S303, if yes, then determining that all the changes in the angular displacement comply with the angular displacement change rule for a weld;

[0098] Specifically, in this embodiment, it is respectively determined whether both the first half of the change in the angular displacement and the second half of the change comply with the 25 angular displacement change rule for a weld; it may be determined that a change in the angular displacement complies with the angular displacement change rule for a weld only when the first half of the change and the second half of the change both fulfill the requirements. By this step, a problem of inaccurate weld determination caused by pipeline size change may be avoided;

[0099] S400, recording all angular displacement changes that comply with the angular 30 displacement change rule for a weld and generating weld signals. Specifically, in this embodiment, fouling existed in the pipeline is taken into consideration; the mileage measurement device will detect changes in the angular displacements when it passes through the fouling, but the fouling should not affect the mileage measurement of the pipeline. Therefore, after determining that the change in the angular displacement complies with the angular displacement 5 change rule for a weld, according to this embodiment, it is also determined whether a region involving a change in the angular displacement has an actual weld. The specific process steps are:

[00100] S401, determining, for each weld signal, whether the change in the angular displacement complies with the image change rule for a weld according to circumferential images;

[00101] S402, extracting, from weld signals, all angular displacement changes that comply with 10 the image change rule for a weld;

[00102] S403, recording all angular displacement changes that comply with the image change rule for a weld;

[00103] S404, generating target weld information according to the angular displacement changes । that comply with the image change rule tor a weld; 15

[00104] S405, recording, for weld signals, all angular displacement changes that do not comply J with the image change rule for a weld;

[00105] S406, generating pipeline corrosion information according to the angular displacement changes that do not comply with the image change rule for a weld.

[00106] Specifically, in this embodiment, for each weld signal, by determining whether weld 20 characteristics are detected for circumferential images in a region involving angular displacement change (grayscale changes are found all around for an image in this region), a target weld information representative of actual weld may be obtained, thereby improving the accuracy of weld identification.

[00107] The specific steps for determining whether the image change rule for a weld has been 25 complied are shown in Fig. 12. The specific steps are:

[00108] S4011, obtaining an image position for each assumptive weld according to the weld signals and the circumferential images;

[00109] S4012, determining whether all photoelectric sensors in the mileage measurement device detect changes in pixel grayscale at the image position of the assumptive weld; 30

[00110] S4014, if not, then the angular displacement changes corresponding to said image position of the assumptive weld are recorded as pipeline fouling information;

[00111] S4013, if yes, then for the angular displacement changes corresponding to said image position of the assumptive weld, it is determined that the image change rule for a weld has been complied with. 5

[00112] Specifically, in this embodiment, although the impact of fouling at one single point on mileage measurement may be ignorable, measurement length of pipelines may variate; when the measurement length is relatively large, fouling still needs to be taken into consideration. Therefore, in this embodiment, after determining that some of the angular displacement changes for the weld signals correspond to actual welds, the angular displacement changes for which the 10 image change rule for a weld is not been complied with are extracted, and are used as fouling information; all fouling information is aggregated / summarized into a pipeline corrosion information, so as to further improve an accuracy in pipeline mileage measurement in subsequent calculations. j

[00113] S500: calculating the actual mileage of the mileage measurement device running in the 15 pipeline to be detected according to the circumferential images and weld information. J Specifically, in this embodiment, the step of calculating the actual mileage of the mileage ■ measurement device running in the pipeline to be detected includes: '

[00114] S501, calculating corrosion influencing factors according to the pipeline corrosion information; 20

[00115] S502, calculating a basic mileage of the mileage measurement device running in the pipeline to be detected according to the target weld information and circumferential images;

[00116] S503, calculating an actual mileage of the mileage measurement device running in the pipeline to be detected according to the corrosion influencing factors and the basic mileage.

[00117] In this embodiment, the actual mileage of the mileage measurement device running in 25 the pipeline to be detected is obtained by: analyzing the target weld information (the influence of the actual welds), the circumferential image (the actual image inside the pipeline) and the corrosion influencing factors (the influence of fouling on the entire pipeline to be detected), thus ensuring the accuracy of pipeline mileage measurement to the greatest extent, and completely avoiding the impact caused by slippage within the pipeline, so as to facilitate subsequent defect 30 locating and constructing.

[00118] Referring to Fig. 13, it can be further seen that, in some embodiments, the mileage measurement method also includes:

[00119] S600, obtaining all pipeline fouling information;

[00120] S700, generating pipe fouling locations according to each pipe fouling information and 5 the circumferential images.

[00121] Specifically, in this embodiment, the steps S600-S700 provided can provide accurate pipeline fouling locations for subsequent defect locating, thereby optimizing subsequent constructing efficiency. 01 08 24

Claims

1. A photoelectric sensor-based mileage measurement device for a detector within pipeline, wherein the mileage measurement device is movably provided in the pipeline and comprises:an inner detector (1);three mileage wheel support arms (2) which are uniformly distributed in a circumferential direction of the inner detector (1), wherein one end of each mileage wheel support arm (2) is hinged with the inner detector (1), and the other end of each mileage wheel support ami (2) is provided with a mileage wheel (3); when the mileage measurement device moves within the pipeline to be detected, the mileage wheels (3) always abut against an inner wall of the pipeline to be detected;angular displacement sensors (4) provided at respective hinged positions of the mileage wheel support arms (2) with the inner detector (1). wherein the angular displacement sensors are electrically coupled to the inner detector (1) for detecting changes in angular displacement between the mileage wheel support arms (2) and the inner detector (1), and generate weld signals that are fed back to the inner detector (1);photoelectric sensors (5) provided in front of respective mileage wheels (3) in a travelling direction, wherein the photoelectric sensors are electrically coupled to the inner detector (1) for obtaining circumferential images of the inner wall of the pipeline to be detected, wherein the circumferential images are fed it back to the inner detector (1);wherein the inner detector (1) is configured to calculate an actual mileage traveled by the mileage measurement device in the pipeline to be detected based on the circumferential images and the weld signals,2. The photoelectric sensor-based mileage measurement device for a detector within pipeline according to claim 1, wherein each mileage wheel support arm (2) comprises a first mileage wheel support arm (21) and a second mileage wheel support ami (22);one end of the first mileage wheel support arm (21) is hinged to the inner detector (1) at aside of away from the inner wall of the pipeline to be detected, with several limiting springs being provided at connection between the first mileage wheel support arm (21) and the inner detector (1);the other end of the first mileage wheel support arm (21) is detachably connected with one end of the second mileage wheel support arm (22), with the photoelectric sensor (5) being provided at the other end of the second mileage wheel support arm (22);the mileage wheel (3) is pivotally connected between the first mileage wheel support arm (21) and the second mileage wheel support arm (22).

3. The photoelectric sensor-based mileage measurement device for a detector within pipeline according to claim 2, wherein a first device connection surface and a second device connection surface are respectively provided at two sides of the mileage wheel (3) in the travelling direction, wherein the first mileage wheel support arm (21) is hinged to the mileage wheel (3) on the first device connection surface, and the second mileage wheel support arm (22) is coupled to the mileage wheel (3) on the second device connection surface;wherein the photoelectric sensor (5) comprises:a sensor carrier (51) coupled with the second mileage wheel support arm (22); anda photoelectric sensing unit (52) arranged on one side of the sensor carrier (51) that is away from the mileage wheel (3).

4. The photoelectric sensor-based mileage measurement device for a detector within pipeline according to claim 3, whereinan X-shaped snap-in slot (211) is provided at one end of the first mileage wheel arm (21) that is away from the inner detector (1);an X-shaped snap-in post (221) is provided at the connection between the second mileage wheel support arm (22) and the first mileage wheel support arm (21); andthe X-shaped snap-in post (221) matches with the X-shaped clamping slot (211);wherein the mileage measurement device further comprises:covering caps (6) respectively snapped on both of the first device connection surface and the second device connection surface, wherein the covering cap (6) comprises a first covering cap (61) that is snapped on one side of the first device connection surface and a second covering cap (62) that is snapped on one side of the second device connection surface; anda spring (7) provided between the first mileage wheel support arm (21) and the second mileage wheel support arm (22).

5. A photoelectric sensor-based mileage measurement method for a detector within pipeline applying a photoelectric sensor-based mileage measurement device for a detector within pipeline according to any one of claim 1-4, wherein the mileage measurement method comprises:obtaining circumferential images inside the pipeline to be detected;obtaining multiple changes in the angular displacement between the first mileage wheel arm and the inner detector when the mileage detection device is running in the pipeline to be detected;determining whether all changes in the angular displacement comply with an angular displacement change rule for a weld;recording all changes in the angular displacement that comply with the angular displacement change rule for a weld and generating weld signals; andcalculating the actual mileage travelled by the mileage measurement device in the pipeline to be detected according to the circumferential images and weld signals.

6. The photoelectric sensor-based mileage measurement method for a detector within pipeline according to claim 5, after the recording all changes in the angular displacement that comply with the angular displacement change rule for a weld and generating weld signals, the mileage measurement method further comprises:determining, for each weld signal, whether the change in the angular displacement complies with the image change rule for a weld according to circumferential images;extracting, from weld signals, all angular displacement changes that comply with the image change rule for a weld;recording all angular displacement changes that comply with the image change rule for a weld;generating target weld information according to the angular displacement changes that comply with the image change rule for a weld;recording, for weld signals, all angular displacement changes that do not comply with the image change rule for a weld; andgenerating pipeline corrosion information according to the angular displacement changes that do not comply with the image change rule for a weld.

7. The photoelectric sensor-based mileage measurement method for a detector within pipeline according to claim 6, wherein the calculating the actual mileage travelled by the mileage measurement device in the pipeline to be detected according to the circumferential images and weld signals comprises:calculating corrosion influencing factors according to the pipeline corrosion information;calculating a basic mileage travelled by the mileage measurement device in the pipeline to be detected according to the target weld information and the circumferential images;calculating an actual mileage travelled by the mileage measurement device in the pipeline to be detected according to the corrosion influencing factors and the basic mileage.

8. The photoelectric sensor-based mileage measurement method for a detector within pipeline according to claim 7, wherein the change in the angular displacement comprises a first half of the change and a second half of the change, the angular displacement change rule for a weld is that the angle first becomes smaller and then becomes larger; wherein the determiningwhether all changes in the angular displacement comply with an angular displacement change rule for a weld comprises:determining whether the first half of the change indicates a decrease of the angle;if not, recording the change in the angular displacement as pipeline fouling information;if yes, determining whether the second half of the change indicates an increasement of the angle;if not, recording the change in the angular displacement as pipeline fouling information;if yes, determining that all the changes in the angular displacement comply with the angular displacement change rule for a weld.

9. The photoelectric sensor-based mileage measurement method for a detector within pipeline according to claim 8. wherein the determining, for each weld signal, whether the change in the angular displacement complies with the image change rule for a weld according to circumferential images comprises:obtaining an image position for each assumptive weld according to the weld signals and the circumferential images;determining whether all photoelectric sensors in the mileage measurement device detect changes in pixel grayscale at the image position of the assumptive weld;if not, recording the angular displacement changes corresponding to said image position of the assumptive weld as pipeline fouling information;if yes, determining that for the angular displacement changes corresponding to said image position of the assumptive weld, the image change rule for a weld has been complied with.

10. The photoelectric sensor-based mileage measurement method for a detector within pipeline according to claim 9, wherein the mileage measurement method further comprises:obtaining all pipeline fouling information;generating pipe fouling locations according to each pipe fouling information and thecircumferential images.

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