Cable duct bank structure steel bar detection device and detection method based on magnetic gradient method

Abstract

The invention discloses a cable duct bank structure steel bar detection device and detection method based on a magnetic gradient method, and belongs to the technical field of pipeline detection, the detection device comprises a magnetic gradiometer for measuring cable duct bank structure steel bars by using the magnetic gradient method, a sleeve and an external support; the sleeve comprises a straight rod, a fixing ring and an adjusting bolt; the multiple straight rods are in the same direction and are annularly arranged in space. The fixing rings are perpendicular to the straight rods and are connected with the straight rods at uniform intervals; the adjusting bolt is mounted at the joint of the straight rod and the fixing ring and is used for assisting in fixing the magnetic gradiometer for detection; the external support comprises an inclined supporting rod, a spring device and a supporting wheel, the inclined supporting rod is hinged to the end of the straight rod, the spring device is hinged to the inclined supporting rod, the supporting wheel is connected with the two ends of the spring device, and the external support is supported on the pipeline inner wall of the cable duct bank and used for walking of the device. The cable duct bank structure reinforcing mesh detection device is light in weight, stable in structure and high in adaptability, and detection personnel can detect the cable duct bank structure reinforcing mesh more conveniently and quickly.

Description

Technical Field

[0001] The present invention belongs to the technical field of pipeline detection, and in particular, relates to a cable pipe structure steel bar detection device and a detection method based on a magnetic gradient method. Background Art

[0002] As an important civil engineering ancillary facility for cables, cable conduits can provide space for cable laying and installation, and can use their own strength and rigidity to provide basic protection for cables. They have the advantages of good economy and convenient cable laying. With the increasing demand for urban construction, cable conduits have also developed rapidly. Taking Shanghai as an example, the total mileage of cable conduits in Shanghai has exceeded 2,000 kilometers, and is growing rapidly at a rate of nearly 100 kilometers per year.

[0003] However, due to objective and subjective factors such as tight construction period, heavy tasks, and weak sense of responsibility of the construction party, the quality of cable pipe construction varies, resulting in reduced structural strength and poor project quality. In particular, the straight-line laying section connecting the horizontal directional drilling and dragging method (hereinafter referred to as directional drilling and dragging pipe) and the work well, as well as the open-cut MPP pipeline when crossing the road, there have even been undesirable phenomena of not encapsulating the pipeline with reinforced concrete box according to the design requirements, but abandoning the steel bar sub-project and directly using plain concrete to encapsulate the pipeline, which has buried hidden dangers for the safe operation of the urban power grid.

[0004] In order to ensure the safe operation of the power grid, the in-well magnetic gradient method is usually used to detect cable pipes. The in-well magnetic gradient method is a passive source detection method, which is generally suitable for the detection of deeply buried metal pipelines. In actual engineering, the magnetic gradient value of the metal pipeline within the borehole depth is detected from top to bottom, and the position and burial depth of the deeply buried metal pipeline are determined according to the change of the gradient value curve. At present, this method is mainly used to detect metal pipelines and pile foundation steel cages, but in theory it can also be used to detect steel mesh in the cable pipe box. However, since the cable pipe is arranged horizontally, it is difficult for the magnetic gradiometer to pass through the cable pipe.

[0005] Therefore, there is an urgent need for a traveling device that can detect the length of the steel mesh of the cable conduit structure in the cable conduit. Summary of the invention

[0006] In order to solve the deficiencies in the prior art, the present invention provides a cable pipe structure steel mesh layout length detection running device based on the magnetic gradient method. The device can carry a magnetic gradient meter and smoothly travel in the cable pipe, facilitating the detection of the cable pipe structure steel mesh.

[0007] The present invention adopts the following technical solution.

[0008] The first aspect of the present invention discloses a cable tube structure steel bar detection device based on the magnetic gradient method, comprising a magnetic gradient meter for measuring the cable tube structure steel bar using the magnetic gradient method, a sleeve and an external bracket;

[0009] The sleeve comprises: a straight rod, a fixing ring and an adjusting bolt; the plurality of straight rods are in the same direction and are arranged in a ring shape in space; the fixing ring is arranged vertically to the straight rod and connected to the straight rod at uniform intervals; the adjusting bolt is installed at the connection between the straight rod and the fixing ring to assist in fixing the magnetic gradiometer for detection;

[0010] The external bracket includes an oblique support rod, a spring device and a support wheel. The oblique support rod is hinged to the end of the straight rod, the spring device is hinged to the oblique support rod, the support wheel is connected to both ends of the spring device, and the external bracket is supported on the inner wall of the cable duct and is used for the movement of the detection device.

[0011] Preferably, the sleeve includes a front baffle and a rear baffle, and both ends of the straight rod are fixedly connected to the front baffle and the rear baffle;

[0012] The front baffle is fixedly connected with a wire hook for fixing a wire dragging device.

[0013] Preferably, the adjusting bolt is provided with a gasket at the end of the screw rod, and the gasket is clamped with the bolt.

[0014] Preferably, two oblique support rods are hinged at each end of the straight rod. If the device is regarded as a cylinder, the oblique support rods are grouped in two, extending outward in the radial direction while approaching each other, and tilting toward the middle of the cylinder in the axial direction.

[0015] Preferably, the spring device is arranged in parallel with the straight rod and is clamped between the inclined support rods close to each other.

[0016] Preferably, the front and rear sections of the spring device are connecting rods, and the middle section is a sleeve structure. The sleeve structure is combined with the inner column through an outer sleeve. The inner column is arranged inside the outer sleeve and can be freely extended and shortened.

[0017] Preferably, a spring is provided in the middle of the spring device and is clamped between the limit nuts. The spring can be adjusted in tightness by using the limit nuts so that the free length of the spring is greater than the working length, and the reaction force of the spring is used to support the external bracket.

[0018] Preferably, the support wheel is connected to the raised wheel axles at both ends of the spring device, and is tightly connected to the inner wall of the pipe under the pushing action of the spring.

[0019] Preferably, the cable conduit running device is made of non-magnetic material.

[0020] The second aspect of the present invention discloses a cable tube structure steel bar detection method based on the magnetic gradient method, and the cable tube structure steel bar detection device based on the magnetic gradient method comprises the following steps:

[0021] Place the cable pipe structure steel bar detection device into the cable pipe to be detected, and adjust the limit nut to support the support wheel in the pipe;

[0022] After the adjustment is completed, take out the detection device, unscrew the adjustment bolt, put the magnetic gradiometer into the sleeve of the walking device, and screw in the adjustment bolt to fix the magnetic gradiometer;

[0023] The traveling device is dragged inside the pipes to collect the magnetic field values ​​of each length at equal intervals. By processing and analyzing the collected data, it is determined whether the pipe gallery contains steel bars and the corresponding length position to complete the detection.

[0024] Compared with the prior art, the beneficial effects of the present invention include at least:

[0025] 1. The present invention adopts a straight rod, a fixed ring, and front and rear baffles to form a hollow sleeve structure, which is light in weight and, in combination with the oblique support rod, makes the device structure stable. The adjusting bolts on the fixed ring can not only fix the magnetic gradiometer, but also facilitate the disassembly of the magnetic gradiometer. The hollow sleeve structure protects the magnetic gradiometer while maintaining a high strength.

[0026] 2. The present invention adopts a spring and hinge structure. The reaction force generated by the compression of the spring supports the external bracket, so that the external bracket can rebound freely. It can not only reduce shock, but also make the supporting wheel always in close contact with the inner wall of the pipe. It can be suitable for cable ducts with different inner diameters, thereby improving the adaptability of the device.

[0027] 3. The present invention is made of non-magnetic materials to avoid affecting the accuracy of the magnetic gradiometer.

[0028] 4. The device of the present invention has a simple structure, distinct primary and secondary structures, is easy to assemble in a modular manner, and is convenient to maintain.

[0029] 5. The device of the present invention is easy to use and is convenient for detecting the length of the steel mesh of the cable pipe structure. It can effectively curb the bad behavior of cutting corners by omitting the steel bar sub-project and strengthen the control of construction quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the structure of the sleeve;

[0032] Figure 3 is a schematic diagram of the structure of the external bracket;

[0033] Figure 4 It is a schematic diagram of the structure of the spring device and the support wheel;

[0034] Figure 5 It is a partial enlarged view of the spring;

[0035] Figure 6 It is a schematic diagram of the spring device, the support wheel and the oblique support rod in the pipeline;

[0036] Numbers in the figure: 1—sleeve; 11—straight rod; 12—fixing ring; 13—adjusting bolt; 14—front baffle; 15—rear baffle; 16—wire hook; 131—gasket; 2—external bracket; 21—inclined support rod; 22—spring device; 23—support wheel; 221—connecting rod; 222—outer sleeve; 223—inner rod; 224—spring; 225—limiting nut; 226—raised wheel axle. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only embodiments of a part of the present invention, rather than all embodiments. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0038] Embodiment 1 of the present invention provides a cable pipe structure steel bar detection running device based on magnetic gradient method, such as Figure 1-5 As shown, it comprises a sleeve 1 and three identical external brackets 2 , wherein the sleeve 1 comprises a straight rod 11 , a fixing ring 12 , an adjusting bolt 13 , a front baffle 14 , a rear baffle 15 and a wire hook 16 .

[0039] There are three straight rods 11, which are evenly arranged in a ring shape. Fixed rings 12 are set at intervals to connect the straight rods 11. Adjusting bolts 13 are installed at the connection between the straight rods 11 and the fixed rings 12 to fix the magnetic gradiometer. The wire hook 16 is located at the front end of the device to facilitate towing the device.

[0040] The external bracket 2 has three parts, including an inclined support rod 21, a spring device 22, and a support wheel 23. The external bracket 2 can use the spring device 22 to tightly support the support wheel 23 on the inner wall of the pipe so that it can slide inside the pipe.

[0041] like Figure 2As shown, the cylindrical cavity structure formed by the straight rod 11, the fixing ring 12, the front baffle 14 and the rear baffle 15 can be used to carry a magnetic gradiometer for detecting the length of the steel mesh of the cable pipe structure. By screwing in or out the adjusting bolt 13, the gasket 131 can press the magnetic gradiometer to form a clamping force to fix the magnetic gradiometer. The wire hook 16 at the front end of the device is used to fix the wire when in use, so as to facilitate towing the device.

[0042] The washer 131 is disposed at the end of the screw of the adjusting bolt 13 . The washer 131 is engaged with the adjusting bolt 13 , thereby enhancing the fixing ability of the adjusting bolt 13 and preventing the screw from scratching the magnetic gradiometer.

[0043] like Figure 3 As shown, each external bracket 2 is hinged to two straight rods 11 through four hinge points, and there are 12 oblique support rods 21 in total, and both ends of each oblique support rod 21 are hinged to the straight rod 11 and the spring device 22 respectively;

[0044] The spring device 22 is arranged in parallel with the straight rod 11 and is hingedly connected to the oblique support rod 21 . Both ends of the spring device 22 are clamped between two oblique support rods 21 that are close to each other.

[0045] Considering the device as a cylinder, the oblique support rods 21 are arranged in groups of two, extending outwards in the radial direction of the cylinder while being close to each other, and tilting toward the middle of the cylinder in the axial direction of the cylinder. This structure has strong stability.

[0046] like Figure 4-5 As shown, the front and rear sections of the spring device 22 are connecting rods 226, and the middle part is a sleeve structure, which includes an outer sleeve 222 and an inner column 223. The outer sleeve 222 and the inner column 223 can be freely extended and shortened;

[0047] There is a spring 224 in the middle of the spring device 22, which is stuck between the limit nuts 225. The free length of the spring is greater than the working length. The limit nuts 225 can be used to adjust the tightness, and the reaction force of the spring 224 is used to support the external bracket 2; the support wheel 23 is connected to the raised wheel axles 226 at both ends of the spring device 22. Under the pushing action of the spring 224, the support wheel 23 is in close contact with the inner wall of the pipe and has a certain shock absorption and adaptive effect.

[0048] In order to ensure the accuracy of magnetic gradiometer detection, the entire device is made of non-magnetic materials such as engineering plastics and copper.

[0049] like Figure 6As shown, in use, the support wheel 23 will be in close contact with the inner wall of the pipeline, and under the pressure, the inclined support rod 21 will rotate inward (as shown by the arrow), while compressing the spring device 22. Under the reaction force of the spring, the entire external bracket tends to arch outward, so that the support wheel is always in effective contact with the inner wall of the pipeline, so that the device can move forward stably in the pipeline.

[0050] Embodiment 2 of the present invention provides a detection method of a cable pipe structure steel bar detection device based on a magnetic gradient method, and the specific steps are as follows:

[0051] S1. Place the running device into the cable pipe to be detected, and adjust the limit nut to make the support wheel properly supported in the pipe;

[0052] S2. After the adjustment is completed, take out the running device, unscrew the adjusting bolt, put the magnetic gradiometer into the running device sleeve, and screw in the adjusting bolt to fix the magnetic gradiometer firmly;

[0053] S3. Drag the running device inside the pipes and collect the magnetic field values ​​of each length at equal intervals. By processing and analyzing the collected data, it is possible to determine whether the pipe gallery contains steel bars and the corresponding length position, thus completing the detection.

[0054] Compared with the prior art, the beneficial effects of the present invention include at least:

[0055] 1. The present invention adopts a straight rod, a fixed ring, and front and rear baffles to form a hollow sleeve structure, which is light in weight and, in combination with the oblique support rod, makes the device structure stable. The adjusting bolts on the fixed ring can not only fix the magnetic gradiometer, but also facilitate the disassembly of the magnetic gradiometer. The hollow sleeve structure protects the magnetic gradiometer while maintaining a high strength.

[0056] 2. The present invention adopts a spring and hinge structure. The reaction force generated by the compression of the spring supports the external bracket, so that the external bracket can rebound freely. It can not only reduce shock, but also make the supporting wheel always in close contact with the inner wall of the pipe. It can be suitable for cable ducts with different inner diameters, thereby improving the adaptability of the device.

[0057] 3. The present invention is made of non-magnetic materials to avoid affecting the accuracy of the magnetic gradiometer.

[0058] 4. The device of the present invention has a simple structure, distinct primary and secondary structures, is easy to assemble in a modular manner, and is convenient to maintain.

[0059] 5. The device of the present invention is easy to use and is convenient for detecting the length of the steel mesh of the cable pipe structure. It can effectively curb the bad behavior of cutting corners by omitting the steel bar sub-project and strengthen the control of construction quality.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A cable pipe structure steel bar detection device based on magnetic gradient method, comprising a magnetic gradient meter for measuring the cable pipe structure steel bar using magnetic gradient method, characterized in that: The cable tube structure steel bar detection device further comprises: a sleeve (1) and an external bracket (2); The sleeve (1) comprises: a straight rod (11), a fixing ring (12) and an adjusting bolt (13); the plurality of straight rods (11) are arranged in the same direction and in a ring-shaped arrangement in space; the fixing ring (12) and the straight rods (11) are arranged vertically and connected to the straight rods at even intervals; the adjusting bolt (13) is installed at the connection between the straight rod (11) and the fixing ring (12) and is used to assist in fixing the magnetic gradiometer for detection; The external support (2) comprises an oblique support rod (21), a spring device (22) and a support wheel (23); the oblique support rod (21) is hinged to the end of the straight rod (11); the spring device (22) is hinged to the oblique support rod (21); the support wheel (23) is connected to both ends of the spring device (22); the external support (2) is supported on the inner wall of the cable duct and is used for detecting the movement of the device.

2. According to claim 1, a cable pipe structure steel bar detection device based on magnetic gradient method is characterized by: The sleeve (1) comprises a front baffle (14) and a rear baffle (15), and both ends of the straight rod (11) are fixedly connected to the front baffle (14) and the rear baffle (15); The front baffle (14) is fixedly connected with a wire hook (16) for fixing a wire dragging device.

3. According to claim 1, a cable pipe structure steel bar detection device based on magnetic gradient method is characterized in that: The adjusting bolt (13) is provided with a washer (131) at the end of the screw rod, and the washer (131) is clamped with the bolt (13).

4. According to claim 1, a cable pipe structure steel bar detection device based on magnetic gradient method is characterized in that: Each end of the straight rod (11) is hinged to two oblique support rods (21). If the device is regarded as a cylinder, the oblique support rods (21) are arranged in groups of two, extending outward in the radial direction while approaching each other, and tilting toward the middle of the cylinder in the axial direction.

5. The cable pipe structure steel bar detection device based on magnetic gradient method according to claim 1 is characterized by: The spring device (22) is arranged in parallel with the straight rod (11) and is clamped between the inclined support rods (21) that are close to each other.

6. The cable pipe structure steel bar detection device based on magnetic gradient method according to claim 5 is characterized by: The front and rear sections of the spring device (22) are connecting rods (221), and the middle section is a sleeve structure. The sleeve structure is connected to the inner column (223) through an outer sleeve (222). The inner column (223) is arranged inside the outer sleeve (222) and can be freely extended and shortened.

7. The cable pipe structure steel bar detection device based on magnetic gradient method according to claim 6 is characterized by: A spring (224) is provided in the middle of the spring device (22) and is clamped between the limiting nuts (225). The spring (224) can be adjusted in tightness by using the limiting nuts so that the free length of the spring (224) is greater than the working length. The reaction force of the spring (224) is used to support the external bracket (2).

8. The cable pipe structure steel bar detection device based on magnetic gradient method according to claim 1 is characterized by: The support wheel (23) is connected to the raised wheel shafts (226) at both ends of the spring device (22), and is tightly connected to the inner wall of the pipeline under the pushing action of the spring (224).

9. The cable pipe structure steel bar detection device based on magnetic gradient method according to claim 1, characterized in that: The cable conduit running device is made of non-magnetic material.

10. A cable tube structure steel bar detection method based on magnetic gradient method, based on a cable tube structure steel bar detection device based on magnetic gradient method according to any one of claims 1 to 9, characterized in that: The following steps are involved: The cable pipe structure steel bar detection device is placed in the cable pipe to be detected, and the limiting nut (225) is adjusted so that the support wheel (23) is supported in the pipe; After the adjustment is completed, take out the detection device, unscrew the adjustment bolt (13), place the magnetic gradiometer into the sleeve (1) of the walking device, and screw in the adjustment bolt (13) to fix the magnetic gradiometer; The traveling device is dragged inside the pipes to collect the magnetic field values ​​of each length at equal intervals. By processing and analyzing the collected data, it is determined whether the pipe gallery contains steel bars and the corresponding length position to complete the detection.

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