A tank wall automatic creeping magnetic flux leakage detector

Abstract

The present invention discloses an automatic crawling magnetic flux leakage detector for tank wall, which adopts a four-wheel drive walking mechanism, and connects a brushless DC motor and a brake on both sides of the walking wheel. The motor controller controls the start and stop of the motor to realize the forward and stop of the detector; the stepper motor controls the rotation of four wheel frames through a series of power transmission, so as to achieve the purpose of equipment steering and line change detection; the lifting mechanism is powered by the lifting motor, and the lifting and lowering movement of the excitation mechanism is realized by controlling the movement of the lifting platform and the lifting rod, so as to achieve the purpose of equipment crossing the weld. In order to ensure that the position of the excitation structure remains unchanged after crossing the weld, the circumferential and axial displacements of the excitation mechanism are limited by the lifting mechanism circumferential limit device and the limit device. The detector is wirelessly connected to the external host, and the motion operation of the equipment and the wireless real-time transmission of data are realized through industrial-grade WIFI, and the signal waveform is displayed in real time.

Description

Technical Field

[0001] The invention relates to the field of nondestructive testing of storage tank walls, in particular to a magnetic flux leakage detector used for testing storage tank walls. Background Art

[0002] Storage tanks are important storage containers for crude oil, refined oil and various chemical production raw materials in the petroleum and petrochemical industries. The media they store are mostly corrosive, and the storage tanks are also affected by the local natural environment. The tank walls are prone to corrosion.

[0003] The water accumulation part of the tank bottom, the raw material part, and the gas combination part on the top of the tank body are more prone to corrosion. The welded part on the top of the tank and the place where the top cover and the cylinder are connected are also prone to corrosion. The water accumulation area on the bottom of the tank is very prone to regional corrosion, which has the most serious impact on the safety of the entire tank body. Once a problem occurs in the tank, it will have a serious impact on the economy and the environment, and even directly endanger human life. We cannot afford the safety accidents caused by the leakage of the tank, so we need to inspect the tank regularly.

[0004] Since the current tank wall inspection methods require equipment such as scaffolding, the actual operation is very inconvenient and has certain risks. The inspection requires high labor intensity and a long construction period. With the increase in domestic storage tanks, the inspection tasks are gradually becoming heavier. The transmission inspection method is no longer suitable for the requirements of the new era and needs to be replaced by a new technology.

[0005] With the emergence and development of intelligent processing systems and the need for safe operations, it has become inevitable to use automated detection technology to replace manual operations. After using automated detection devices, the detection cost of tank wall panels will be greatly reduced, the efficiency will be significantly improved, and most importantly, the danger to operators during the detection process will be reduced. Therefore, it is very necessary to design an automated device suitable for magnetic flux leakage detection of tank wall panels. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art, solve the problems of high risk and high labor intensity in traditional tank wall detection, and provide an automatic crawling magnetic leakage detector for the tank wall.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] An automatic crawling magnetic flux leakage detector for a tank wall comprises a vehicle body, an excitation mechanism, a lifting motor, a lifting rod, a lifting platform, a width direction limit device, a support rod, a reduction gear set, a stepping motor, a transmission system, a wheel frame, a DC brushless motor, a traveling wheel, a brake, a motor fixing frame, a frame and a length direction limit device;

[0009] The reduction gear set, stepper motor, transmission system and frame are all fixed on the vehicle body. A through hole is provided in the middle of the vehicle body. The reduction gear set and the motor fixing frame are fixed above the through hole through the frame. The input shaft of the reduction gear set is connected to the lifting motor, and the output shaft is connected to the lifting platform. The lifting motor is installed on the motor fixing frame. The lower part of the lifting platform is connected to the excitation mechanism through the lifting rod. Slide grooves are provided on both sides of the vehicle body. The length direction limiting device is slidably connected in the slide groove. The length direction limiting device is connected to the excitation structure and is used to limit the axial displacement of the excitation mechanism. The width direction limiting device is connected to the lifting platform and ensures the position of the excitation mechanism by limiting the circumferential displacement of the lifting platform.

[0010] The wheel frames are arranged on both sides of the vehicle body, each wheel frame is provided with a traveling wheel, and the stepper motor transmits power to the wheel frames through a transmission system to realize the steering and traveling functions of the traveling wheels; the brushless DC motor and the brake are respectively arranged on both sides of each wheel frame.

[0011] Furthermore, the length-direction limiting device separates the excitation mechanism from the vehicle body, thereby preventing the excitation mechanism from wearing against the vehicle body during the lifting process.

[0012] Furthermore, the transmission system consists of two rotating gears, two transmission gears, two worm wheels, a reversing gear and a worm; the worm is meshingly connected with the worm wheel, the worm wheel is coaxial with the transmission gear, the transmission gear on one side of the worm is meshingly connected with one of the rotating gears, thereby driving the rotating shaft of the rotating gear, the rotating shaft of the rotating gear is connected to the wheel frame by bolts, thereby realizing the rotation of the wheel frame; the transmission gear on the other side of the worm is meshingly connected with the reversing gear and another rotating gear in turn, and the rotation direction of the rotating gear is changed by the reversing gear to achieve consistency in the rotation direction of the two wheels on one side.

[0013] Furthermore, two wheel frames are provided on both sides of the vehicle body; a four-wheel travel drive structure is adopted, and the travel wheels are driven by four DC brushless motors to ensure the power and flexibility of the magnetic flux leakage detector, and prevent the magnetic flux leakage detector from having difficulty in moving due to excessive adsorption force of the magnet.

[0014] Furthermore, the travel wheel is started and braked by a brushless DC motor and a brake, and the brushless DC motor is started and stopped by a motor controller.

[0015] Furthermore, the excitation mechanism ensures that it can return to its previous position after crossing the weld through a length limit device and a width limit device, thereby preventing the detection effect from being affected by the movement of the excitation structure position, and different lifting values ​​can be achieved for wall panels of different thicknesses through the lifting mechanism.

[0016] Furthermore, the magnetic flux leakage detector can be connected to an external computer, and the real-time transmission of wireless data can be realized through a wireless network, and the signal waveform can be real-time.

[0017] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0018] 1. The present invention directly installs a brushless DC motor on four running wheels. With the cooperation of a motor controller and a battery, the motor can drive the running wheels to move, thereby realizing the forward and backward movement of the detection equipment.

[0019] 2. The present invention designs two sets of front and rear steering devices, each set controls two running wheels. Through the transmission system, the torque output by the stepper motor is decelerated and delivered to the wheel frame of the running wheel to realize the rotation of the running wheel. In this way, a set of running wheels can be controlled separately and can be operated in coordination, which can effectively control the size of the turning of the detector and meet various usage conditions;

[0020] 3. The present invention designs an excitation lifting structure, which is powered by a lifting motor. After the speed is reduced by a reduction gear set, the lifting platform is driven to move, and then the excitation structure is driven to lift. A width limiter and a length limiter are designed to ensure that the position of the excitation mechanism remains unchanged before and after lifting.

[0021] 4. The present invention adopts wireless transmission to connect the control signal and detection data of the detector to the operation terminal through the wireless operation control module and the wireless data transmission module, so as to realize the wireless real-time transmission of the control signal and the defect leakage magnetic signal, thereby increasing the operating range of the detector and reducing the workload of the staff;

[0022] 5. The present invention can replace the traditional tank wall detection method, reduce the danger and labor cost of detection personnel, and improve the detection efficiency and economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 3D schematic diagram of the magnetic flux leakage detector in the embodiment of the present invention;

[0024] Figure 2 Schematic diagram of the lifting mechanism in the embodiment of the present invention;

[0025] Figure 3 2 is a schematic diagram of the main structure of a magnetic flux leakage detector according to an embodiment of the present invention;

[0026] Figure 4 1 is a left-side structural schematic diagram of a magnetic flux leakage detector according to an embodiment of the present invention;

[0027] Figure 5 1 is a schematic diagram of a top view of a magnetic flux leakage detector according to an embodiment of the present invention;

[0028] Figure 6 is a schematic diagram of a transmission system in an embodiment of the present invention; DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] Figure 1 The figure shows the tank wall automatic crawling magnetic leakage detector provided in this embodiment, which includes a vehicle body 1, an excitation mechanism 2, a lifting motor 23, a lifting rod 3, a reduction gear set 7, a stepper motor 8, a transmission system 9, a wheel frame 10, a DC brushless motor 11, a walking wheel 12, a brake 13, a motor fixing bracket 24, a frame 17 and a length direction limit device 14.

[0031] In this embodiment, a rectangular through hole is provided in the middle of the vehicle body 1, and a horizontal wing plate and a vertical baffle plate are respectively provided on both sides of the rectangular through hole; the horizontal wing plate and the vertical baffle plate are integrally connected with an arc chamfer, and a reduction gear set 7 and a motor fixing bracket 24 are fixed directly above the rectangular through hole through a frame 17, and the stepper motor 8 and the transmission system 9 are symmetrically fixed on the horizontal wing plates on both sides of the vehicle body 1, and the lifting motor 23 is fixed on the motor fixing bracket 24, and the power is transmitted to the lifting platform 4 through the reduction gear set 7, so as to drive the excitation mechanism to complete the lifting action, and the vertical baffle plates on both sides of the vehicle body 1 are provided with slide grooves, and the slide grooves The inner sliding connection is provided with a length-direction limiting device 14, which is connected to the excitation structure 2 and is used to limit the length-direction displacement of the excitation mechanism 2; the width-direction limiting device 5 is connected to the lifting platform 4, and ensures the position of the excitation mechanism 2 by limiting the width-direction displacement of the lifting platform 4; the lifting platform 4 and the lifting rod 3 are used to realize the lifting and lowering movement of the excitation mechanism 2, so as to achieve the purpose of the equipment crossing the weld. At the same time, in order to ensure that the position of the excitation mechanism 2 before and after lifting remains unchanged, the width-direction limiting device 5 and the length-direction limiting device 14 are used to limit the displacement of the excitation mechanism 2 in width and length.

[0032] There are four wheel frames 10, two in a group symmetrically arranged under the transverse wing plates on both sides of the vehicle body 1, each wheel frame 10 is provided with a running wheel 12, and the stepper motor 8 transmits power to the wheel frame 10 through the transmission system 9 to realize the steering and running functions of the running wheel 12; the DC brushless motor 11 and the brake 13 are respectively arranged on both sides of each wheel frame 10. The stepper motor 8 transmits power to the wheel frame 10 through the transmission system 9 to realize the steering of the running wheel 12, so as to achieve the purpose of equipment steering and line change.

[0033] like Figure 2As shown, the frame 17 is used to fix the lifting platform components, the rotation of the gear 16 drives the rotation of the support rod 6, the support rod 6 is connected to the lifting platform 4 by a threaded connection, drives the movement of the lifting platform 4, and the lifting rod 3 fixed to the lifting platform 4 drives the lifting movement of the excitation mechanism 2 with the lifting movement of the lifting platform; in order to ensure that the position of the excitation mechanism 2 remains unchanged before and after crossing the weld, its width direction movement is limited by the lifting width direction limit device 5, the width direction limit device 5 is connected to the circumferential limit plate 15, the circumferential limit plate 15 limits the movement of the width direction limit device 5, and the width direction limit device 5 limits the movement of the lifting platform 4, thereby realizing the circumferential displacement limitation of the excitation mechanism.

[0034] like Figure 3 As shown, the detector of the present invention adopts a four-wheel drive mode, and each of the two sides of each walking wheel 12 contains a DC brushless motor 11 and a brake 13. The motor controller controls the start and stop of the DC brushless motor 11 to realize the forward and backward movement of the equipment, and the brake 13 is used to control the travel speed of the equipment; the four-wheel drive mode can ensure that the equipment has sufficient power during detection, and can also ensure the flexible movement of the equipment, so as to realize the equipment steering, line change detection and other actions.

[0035] like Figure 4 As shown, the input shaft of the transmission system 9 is connected to the stepper motor 8, and the output shaft of the transmission system 9 is connected to the wheel frame 10. The three are fixed on the vehicle body 1, and the stepper motor 8 provides power. The transmission system 9 transmits the power of the motor to the wheel frame 10 through the worm gear, worm and gears. The rotation of the wheel frame 10 drives the rotation of the running wheel 12 to achieve the steering, line change inspection and other requirements of the equipment; in order to ensure the consistency of the rotation of the two running wheels 12, it is necessary to add a reversing gear in the transmission system 9 of one of the wheels to adjust the rotation direction of the wheel frame 10.

[0036] like Figure 5 As shown, the steering of the walking wheels 12 on both sides is controlled by two stepping motors 8 respectively, which makes it more convenient and flexible to operate the equipment; the lifting platform 4 and the excitation mechanism 2 are located in the middle of the equipment, and the lifting motor 23 transmits power to the reduction gear group 7, and transmits power to the lifting platform through a group of reduction gears, thereby driving the lifting and lowering of the excitation mechanism 2.

[0037] like Figure 6 As shown, the transmission system 9 consists of two rotating gears 18, two transmission gears 20, two worm wheels 22, a reversing gear 19 and a worm 21; the worm 21 transmits the power of the motor to the worm wheels 22 on both sides, thereby driving the transmission gears 20 coaxial with the worm wheels 22, one of which is directly meshed with the rotating gear, thereby driving the rotation of the wheel frame, and the transmission gear 20 on the other side is meshed with the reversing gear 19, and the rotation direction of the rotating gear 18 is changed by the reversing gear 19, so that the rotation direction of the two wheels on one side is consistent.

[0038] In addition, those skilled in the art should understand that the drawings provided are only for the purpose of illustrating the purpose, features and advantages of the present invention, and the drawings are not actually drawn to scale. At the same time, unless the context clearly requires, the words "include", "comprise" and the like in the entire specification and claims should be interpreted as inclusive rather than exclusive or exhaustive; that is, "including but not limited to" means.

[0039] The present invention is not limited to the embodiments described above. The above description of the specific embodiments is intended to describe and illustrate the technical solution of the present invention. The above specific embodiments are merely illustrative and not restrictive. Without departing from the scope of the present invention and the scope of protection of the claims, a person of ordinary skill in the art can also make many forms of specific changes under the guidance of the present invention, which all fall within the scope of protection of the present invention.

Claims

1. A tank wall automatic creeping magnetic flux leakage detector, characterized in that: It comprises a vehicle body (1), an excitation mechanism (2), a lifting motor (23), a lifting rod (3), a lifting platform (4), a width direction limiting device (5), a support rod (6), a reduction gear set (7), a stepping motor (8), a transmission system (9), a wheel frame (10), a DC brushless motor (11), a running wheel (12), a brake (13), a motor fixing frame (24), a frame (17) and a length direction limiting device (14); The reduction gear set (7), the stepper motor (8), the transmission system (9) and the frame (17) are all fixed on the vehicle body (1). A through hole is provided in the middle of the vehicle body (1). The reduction gear set (7) and the motor fixing frame (24) are fixed above the through hole through the frame (17). The input shaft of the reduction gear set (7) is connected to the lifting motor (23), and the output shaft is connected to the lifting platform (4). The lifting motor (23) is installed on the motor fixing frame (24). The lower part of the lifting platform (4) is connected to the excitation mechanism through the lifting rod (3). Slide grooves are provided on both sides of the vehicle body (1). The length direction limiting device (14) is slidably connected in the slide groove. The length direction limiting device (14) is connected to the excitation structure (2) and is used to limit the axial displacement of the excitation mechanism (2). The width direction limiting device (5) is connected to the lifting platform (4) and ensures the position of the excitation mechanism (2) by limiting the circumferential displacement of the lifting platform (4). The wheel frames (10) are arranged on both sides of the vehicle body (1), and a running wheel (12) is arranged in each wheel frame (10). The stepper motor (8) transmits power to the wheel frames (10) through a transmission system (9) to realize the steering and running functions of the running wheels (12); the DC brushless motor (11) and the brake (13) are respectively arranged on both sides of each wheel frame (10); the stepper motor can independently control a group of running wheels and perform coordinated operations to control the size of the turning of the magnetic flux leakage detector; The length direction limiting device (14) separates the excitation mechanism (2) from the vehicle body (1), thereby preventing the excitation mechanism (2) from wearing the vehicle body (1) during the lifting process; The transmission system (9) is composed of two rotating gears (18), two transmission gears (20), two worm wheels (22), a reversing gear (19) and a worm (21); the worm (21) is meshedly connected with the worm wheel (22), the worm wheel (22) is coaxial with the transmission gear (20), the transmission gear (20) on one side of the worm (21) is meshedly connected with one of the rotating gears (18), thereby driving the rotating shaft of the rotating gear (18), the rotating shaft of the rotating gear (18) is connected to the wheel frame (10) by bolts, and the rotation of the wheel frame (10) is realized; the transmission gear (20) on the other side of the worm (21) is meshedly connected with the reversing gear (19) and another rotating gear (18) in sequence, and the rotating direction of the rotating gear (18) is changed by the reversing gear (19), so that the rotation direction of two wheels on one side is consistent.

2. According to claim 1, a tank wall automatic creeping magnetic flux leakage detector is characterized in that: Two wheel frames (10) are respectively provided on both sides of the vehicle body (1); a four-wheel travel drive structure is adopted, and four DC brushless motors (11) drive the travel wheels (12) to ensure the power and flexibility of the magnetic flux leakage detector, and prevent the magnetic flux leakage detector from having difficulty in moving due to excessive adsorption force of the magnet.

3. The tank wall automatic creeping magnetic flux leakage detector according to claim 1, characterized in that: The running wheel (12) is started and braked through a brushless DC motor (11) and a brake (13), and the brushless DC motor (11) is started and stopped through a motor controller.

4. The tank wall automatic creeping magnetic flux leakage detector according to claim 1, characterized in that: The excitation mechanism (2) ensures that it can return to its previous position after crossing the weld through a length-direction limit device (14) and a width-direction limit device (5), thereby preventing the detection effect from being affected by the movement of the position of the excitation structure (2), and different lifting values ​​can be achieved for wall panels of different thicknesses through the lifting mechanism.

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