Winding type elevator steel wire rope optical fiber weak magnetic combination real-time online monitoring method

Abstract

The invention discloses a winding type elevator steel wire rope optical fiber weak magnetic combination real-time on-line monitoring method which comprises the following steps that an optical fiber cable coaxial with a rope core of a steel wire rope is arranged in the rope core of the steel wire rope, and the optical fiber cable and the rope core are kept coaxial and straight through a parallel twisting technology; when the elevator drives the steel wire rope to operate, stress data of all positions of the steel wire rope are collected in real time through an optical fiber sensor arranged in the optical fiber cable and transmitted to a processor. Optical fiber stress monitoring and weak magnetic damage detection are combined, the optical cable and the optical fiber sensor are arranged in the steel wire rope, stress data of all positions of the steel wire rope can be collected in real time, and therefore the overall state of the steel wire rope is monitored; and when abnormal stress change is monitored, quick response can be realized, and fine and accurate flaw detection can be performed through the weak magnetic detection device, so that safety accidents caused by wire breakage, abrasion, corrosion, fatigue and the like of the steel wire rope can be effectively prevented, and the use safety of the steel wire rope of the elevator is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of wire rope monitoring, and in particular to a real-time online monitoring method for a winding type hoist wire rope in combination with optical fiber weak magnetic field. Background Art

[0002] Weak magnetic detection technology is a major innovative achievement in the field of wire rope detection made by Chinese scientists after they successfully discovered the changes and movement laws of the space magnetic field vector situation. In particular, the newly developed TCK.W portable wire rope non-destructive testing product has overcome two major technical difficulties in the field of wire rope non-destructive testing and achieved two major breakthroughs: one is that it can quantitatively detect various damages such as broken wires, wear, rust, fatigue, etc. of the in-use wire rope; the other is that it can correctly evaluate the remaining load-bearing capacity and service life of the tested wire rope. Compared with traditional manual detection, this online automatic monitoring system for wire ropes greatly improves the safety of detection personnel, the stability of detection data and the detection efficiency. However, it still has the following defects: the detection method is single, and because the wire rope needs to pass through the monitoring device continuously during detection, the wire rope is monitored section by section through weak magnetic induction, and the overall state of the wire rope cannot be monitored in real time and comprehensively, resulting in a certain lag in the safety monitoring of the wire rope, which affects the safety of the wire rope and hoist equipment. To this end, we propose a real-time online monitoring method for winding hoist wire ropes combined with optical fiber weak magnetic. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the existing defects and provide a real-time online monitoring method for the weak magnetic field of optical fiber combined with the steel wire rope of a winding hoist. By arranging optical cables and optical fiber sensors in the steel wire rope, stress data of various positions of the steel wire rope can be collected in real time, thereby realizing the overall state monitoring of the steel wire rope, which can effectively solve the problems in the background technology.

[0004] To achieve the above object, the present invention provides the following technical solution: a real-time online monitoring method for weak magnetic bonding of optical fiber of a winding hoist wire rope, comprising the following steps: S1) a coaxial optical fiber cable is arranged in the core of the steel wire rope, and the optical fiber cable is kept coaxial and straight with the core through a parallel twisting process; S2) When the hoist drives the wire rope to run, the optical fiber sensor installed in the optical fiber cable collects the stress data of each position of the wire rope in real time and transmits it to the processor; S3) A weak magnetic detection device is fixedly installed on the main equipment side of the hoist. The weak magnetic detection device is sleeved on the wire rope. When the hoist drives the wire rope to run, the magnetic energy potential difference information on the wire rope is collected, and the wire rope damage such as wire breakage, wear, rust, fatigue, etc. is quantitatively analyzed and the corresponding data is transmitted to the processor; S4) Before the steel wire rope is put into use, it shall be fully inspected by a weak magnetic detection device and put into use only after no damage is found; S5) During the operation of the hoist, when the optical fiber sensor detects that the stress change value of the wire rope exceeds the preset threshold, an alarm is triggered, and the hoist is automatically controlled or manually intervened to stop the load operation, and the hoist is controlled to drive the wire rope to move to the weak magnetic detection device for secondary detection.

[0005] As a preferred technical solution of the present invention, the following steps are also included: S6) After the wire rope has been put into use for a period of time, the weak magnetic detection device is set to a continuous monitoring mode to continuously collect the magnetic energy potential difference information on the wire rope, and the magnetic characteristic data and the optical fiber stress data are subjected to spatiotemporal correlation analysis through the processor.

[0006] As a preferred technical solution of the present invention, a flexible protective sleeve is sleeved on the outer surface of the optical fiber cable.

[0007] As a preferred technical solution of the present invention, the outer surface of the protective sleeve is coated with a protective coating.

[0008] As a preferred technical solution of the present invention, fiber strands are arranged on the outside of the protective coating, and the rope core of the steel wire rope is arranged on the outside of the fiber strands.

[0009] As a preferred technical solution of the present invention, the steel wire rope also includes a plurality of outer steel wire strands arranged outside the rope core.

[0010] As a preferred technical solution of the present invention, a plurality of weak magnetic detection modules and two groups of wide-angle cameras are arranged inside the weak magnetic detection device, and the two groups of wide-angle cameras are respectively arranged at both ends of the plurality of weak magnetic detection modules.

[0011] As a preferred technical solution of the present invention, two groups of long rods and short rods are respectively arranged on both sides of the shell of the weak magnetic detection device, and a guide wheel is respectively arranged on the long rod and the short rod, and the four guide wheels are respectively arranged at the upper and lower ends of both sides of the shell of the weak magnetic detection device.

[0012] As a preferred technical solution of the present invention, the preset threshold in step S5) includes a dynamic change threshold and a static stress threshold, wherein the dynamic change threshold is that the stress change rate of adjacent sampling periods exceeds 10% / s.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: by arranging optical cables and optical fiber sensors in the wire rope, stress data at various positions of the wire rope can be collected in real time, thereby realizing overall state monitoring of the wire rope, and when abnormal stress changes are detected, a quick response can be made and detailed and accurate flaw detection can be performed through a weak magnetic detection device, which can effectively prevent safety accidents caused by wire breakage, wear, rust, fatigue, etc. of the wire rope, greatly improving the safety of the use of the hoist wire rope.

[0014] Combining optical fiber stress monitoring with weak magnetic damage detection forms a collaborative mode of "real-time global monitoring + triggered local precision inspection". At the same time, the trigger logic is optimized: the stress change threshold of optical fiber monitoring triggers the weak magnetic secondary detection, avoiding the high energy consumption problem of continuous operation of weak magnetic equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the cross-sectional structure of the steel wire rope of the present invention; Figure 2 It is a schematic structural diagram of the steel wire rope and the weak magnetic detection device of the present invention.

[0016] In the figure: 1 rope core, 2 outer steel wire strands, 3 optical fiber cable, 4 optical fiber sensor, 5 protective casing, 6 protective coating, 7 fiber strands, 8 steel wire rope, 9 weak magnetic detection device, 10 weak magnetic detection module, 11 wide-angle camera, 12 long rod, 13 short rod, 14 guide wheel. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] See also Figure 1-2 The present invention provides a technical solution: a real-time online monitoring method for the weak magnetic combination of optical fiber of a winding hoist wire rope, comprising the following steps: S1) A coaxial optical fiber cable 3 is arranged inside the rope core 1 of the steel wire rope 8. The optical fiber cable 3 can be arranged in 1 to 3 bundles. The optical fiber cable 3 is twisted synchronously with the rope core 1 at a twist angle of 0.5-1.5° through a parallel twisting process to ensure that the optical fiber cable 3 is in a straight extension state inside the rope core 1, and torsion of the optical fiber cable 3 and the influence on communication sensing are avoided as much as possible.

[0019] The optical fiber cable 3 uses a double-layer acrylic-coated bending-resistant optical fiber, with a bending radius tolerance of ≥5 mm and a tensile strength of ≥100 kpsi.

[0020] The optical fiber of the optical fiber cable 3 can be selected from optical fibers with higher elastic modulus, such as plastic optical fiber, sapphire single crystal optical fiber, composite silicon carbide fiber, or metal-coated optical fiber. The metal-coated optical fiber can be prepared by sputtering a 10-20 μm titanium alloy layer on the optical fiber surface to increase the elastic modulus of the optical fiber, so as to avoid the situation where the elastic modulus of the optical fiber is less than that of the wire rope and the optical fiber breaks during use.

[0021] S2) When the hoist drives the steel wire rope 8 to run, the optical fiber sensor 4 provided in the optical fiber cable 3 collects stress data of each position of the steel wire rope 8 in real time and transmits the data to the processor, which performs analysis, processing and judgment.

[0022] A rotating optical fiber coupler is set on the main equipment side of the hoist, and the end of the optical fiber cable 3 maintains an optical connection with the signal processing unit through the coupler. When the wire rope 8 is running, the optical fiber sensor 4 collects the axial stress distribution data of the wire rope in real time at a sampling frequency of 100-500Hz.

[0023] The optical fiber sensor 4 is preferably a fiber grating sensor (FBG), which has a grating engraved inside the optical fiber. The fiber grating sensor forms a periodic refractive index change in the fiber core and directly senses temperature / strain, etc.; a distributed optical fiber sensor (DTS / DAS) can also be used to detect the strain of the wire rope 8 using the Rayleigh / Raman scattering effect of the optical fiber itself.

[0024] The processor can be a single-chip microcomputer of the STM32H743 series, which is suitable for real-time stress data collection and preliminary processing. You can also use an industrial-grade processor such as the Intel Atom x6425E, which can perform AI-driven damage type recognition and three-dimensional stress model calculations, and is suitable for scenarios where a three-dimensional stress model needs to be established. It integrates an AI acceleration instruction set (Intel DL Boost) through a quad-core processor (1.8GHz), can run machine learning algorithms (such as a wire rope damage determination model), and supports a wide temperature range of -40~85℃, making it suitable for the harsh environment of mines.

[0025] S3) A weak magnetic detection device 9 is fixedly installed on the main equipment side of the hoist. The weak magnetic detection device 9 is sleeved on the wire rope 8. When the hoist drives the wire rope 8 to run, the magnetic energy potential difference information on the wire rope 8 is collected, and the damage of the wire rope 8 such as broken wire, wear, rust, fatigue, etc. is quantitatively analyzed and the corresponding data is transmitted to the processor.

[0026] The weak magnetic detection module 10 and the like are arranged on the weak magnetic detection device 9, and the whole device can adopt the TCK.W steel wire rope online automatic detection system and equipment sold by Luoyang Willup Testing Technology Co., Ltd. The technical principle is: the magnetic energy product established by the detection device along the axial direction of the steel wire rope is equally, evenly and continuously distributed, and the magnetic energy product in any volume element should also be equal and uniform. The density of magnetic lines of force is the same, the magnetic flux is equal, and a given memory magnetic field is thus formed. The memory magnetic field will not disappear with the withdrawal of the external magnetic field, and it will exist stably for a long time as long as there are no severe mechanical vibrations or high temperatures. By collecting the magnetic energy potential difference information on the steel wire rope 8, the damage of the steel wire rope 8, such as broken wires, wear, corrosion, and fatigue, is quantitatively analyzed.

[0027] S4) When the steel wire rope 8 is initially installed, it passes through the weak magnetic detection device 9 continuously at a speed of 0.2-0.5m / s to establish a full-length reference spectrum containing magnetic anisotropy characteristics. When the local magnetic signal deviation is less than 2%, it is judged to be qualified. The whole section is tested by the weak magnetic detection device 9, and it is put into use after no damage is found. If there is damage, the steel wire rope 8 is replaced or further tested manually and the impact on the safety of the hoist operation is evaluated before further processing.

[0028] S5) During the operation of the hoist, when the optical fiber sensor 4 detects that the stress change value of the wire rope 8 exceeds the preset threshold, an alarm is triggered, and the hoist is automatically controlled or manually intervened to stop the load operation, and the hoist is controlled to drive the wire rope 8 to move to the weak magnetic detection device 9 for secondary detection.

[0029] The preset thresholds include a dynamic change threshold and a static stress threshold, where the dynamic change threshold is when the stress change rate in adjacent sampling periods exceeds 10% / s.

[0030] The slow damage changes of the wire rope may not exceed the preset static threshold, resulting in undetectable damage. Therefore, the stress detection of the wire rope can comprehensively compare the stress values ​​of various time periods and usage conditions to achieve the purpose of accurate detection.

[0031] Specifically: During the operation of the hoist, when the optical fiber sensor 4 detects any of the following conditions, a graded alarm is triggered: The instantaneous value of single-point stress exceeds 50-60% of the rated breaking strength of the wire rope; The stress gradient change rate of adjacent 1m sections exceeds 8-12% / s; The stress fluctuation amplitude exceeds the average stress by 15-20% within three consecutive sampling periods; Automatically execute after triggering: a. Cut off the load power supply of the hoist and start the brake device; b. Drive the steel wire rope 8 through the weak magnetic detection device 9 at a speed of 0.3-0.8m / s, and at the same time increase the sampling frequency of the magnetic sensor to 2-5kHz to accurately locate the damage and determine whether the section of the steel wire rope is damaged. If damaged, replace the steel wire rope; if not detected, further manual inspection is performed to determine the cause of stress change, etc.

[0032] S6) After the steel wire rope 8 has been in use for a period of time (400-1600 hours), the surface of the steel wire rope 8 may be damaged while the stress change monitored by the optical fiber sensor is not obvious. The weak magnetic detection device 9 is set to continuous monitoring mode to continuously collect the magnetic energy potential difference information on the steel wire rope 8, and the magnetic feature data and the optical fiber stress data are analyzed in time and space through the processor. The optical fiber stress data and the magnetic detection data are synchronized in time stamp and matched in space position. The safety of the use of the steel wire rope 8 is ensured.

[0033] Optionally, the following steps are also included: establish a three-dimensional stress model for the wire rope, compare and analyze the real-time stress data with the model prediction value, and trigger an abnormal warning when the deviation exceeds 10-15%. The three-dimensional stress model is constructed through a machine learning algorithm, and the training data includes wire rope specification parameters, load condition data, and historical detection data.

[0034] In a preferred technical solution, a flexible protective sleeve 5 is sleeved on the outer surface of the optical fiber cable 3. The protective sleeve 5 can be a commonly used protective sleeve for optical fiber cables 3 to protect the optical fiber cables 3. The protective sleeve 5 can also adopt a double-layer composite structure: the inner layer is thermoplastic polyurethane (TPU) with a thickness of 0.3-0.5 mm; the outer layer can be an aramid fiber braided reinforcement layer with a braiding density of ≥60 mesh / inch, which can absorb the shear stress generated when the steel wire rope is bent and improve the tensile strength of the optical fiber cable 3. The composite protective structure can also reduce the optical fiber microbending loss.

[0035] In a preferred technical solution, the outer surface of the protective sleeve 5 is coated with a protective coating 6 .

[0036] The protective coating 6 may be a polyurea coating layer, which has excellent physical and chemical properties, good tensile strength, elongation, flexibility, wear resistance, aging resistance, corrosion resistance, etc., and has good thermal stability and can be used for a long time at 120°C.

[0037] The protective coating 6 may also be a polyurethane-fluorocarbon composite material layer. The fluorocarbon coating prolongs the salt spray corrosion resistance time and the surface self-cleaning function reduces the dirt adhesion rate by 80%.

[0038] In a preferred technical solution, fiber strands 7 are arranged on the outside of the protective coating 6, and the rope core 1 of the steel wire rope 8 is arranged on the outside of the fiber strands 7. The fiber strands 7 can be made of high modulus polyethylene (HMPE) fiber, with a single filament diameter of 0.12-0.15 mm, and are wound around the outside of the protective coating 6 at a crossing angle of ±15°. The winding tension is controlled at 50-80N, and the difference in elastic modulus between the HMPE fiber and the steel wire strand (HMPE: 120GPa vs steel wire: 210GPa) forms a gradient buffer layer, which reduces local stress concentration by 40%.

[0039] The steel wire rope 8 also includes a plurality of outer steel wire strands 2 arranged outside the rope core 1. The multi-layer steel wire strands 2 may be of a 6×36WS structure, with a steel wire diameter of 0.25-0.35 mm and a spacing of 1-1.5 mm from the fiber wire strands 7.

[0040] The preferred technical solution is that a plurality of weak magnetic detection modules 10 and two groups of wide-angle cameras 11 are arranged inside the weak magnetic detection device 9. The wide-angle camera 11 can use a global shutter CMOS sensor with a field of view of 200°, a resolution of 1280×1024, and a frame rate that can be synchronized with or greater than the moving speed of the wire rope. The two groups of wide-angle cameras 11 are respectively arranged at both ends of the plurality of weak magnetic detection modules 10. No matter when the wire rope 8 is wound upward or moved downward, once the weak magnetic detection module 10 detects damage to the wire rope, the wide-angle camera 11 on the moving direction side can be used to take pictures of the damaged section, and then transmitted to the external display through the processor for reference by the staff.

[0041] The detection surface of the weak magnetic detection module 10 maintains a distance of 20-50 mm from the running track of the wire rope 8, and the wide-angle camera 11 also maintains a distance of 20-50 mm from the running track of the wire rope 8, so as to capture the damaged section of the wire rope 8.

[0042] The wide-angle camera 11, weak magnetic detection device 9, processor, optical fiber sensor, etc. used in this application are all electronic components commonly used in the prior art. Their specific structures, working principles, circuit connections, etc. are all well-known technologies and will not be described in detail here.

[0043] The preferred technical solution is that two groups of long rods 12 and short rods 13 are respectively arranged on both sides of the shell of the weak magnetic detection device 9, and a guide wheel 14 is respectively arranged on the long rod 12 and the short rod 13. The four guide wheels 14 are respectively arranged at the upper and lower ends of both sides of the shell of the weak magnetic detection device 9. The long rod 12 and the short rod 13 are made of 7075 aluminum alloy, the long rod length L=300-500mm, and the short rod length l=150-250mm; the surface of the guide wheel 14 is coated with a polyurethane layer, and a ±5mm adaptive displacement is achieved through a spring buffer mechanism. The guide wheel 14 guides the wire rope 8 to maintain the stability of the weak magnetic detection device 9.

[0044] The undisclosed parts in the present invention are all prior art, and their specific structures, materials and working principles are not described in detail. Although the embodiments of the present invention have been shown and described, it is understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A real-time online monitoring method for optical fiber weak magnetic bonding of a winding hoist wire rope, characterized in that: The following steps are involved: S1) arranging a coaxial optical fiber cable (3) in a rope core (1) of a steel wire rope (8), wherein the optical fiber cable (3) is kept coaxial and straight with the rope core (1) by a parallel twisting process; S2) when the hoist drives the steel wire rope (8) to run, the optical fiber sensor (4) arranged in the optical fiber cable (3) collects stress data of each position of the steel wire rope (8) in real time and transmits the data to the processor; S3) a weak magnetic detection device (9) is fixedly arranged on the main equipment side of the hoist, the weak magnetic detection device (9) is sleeved on the steel wire rope (8), and when the hoist drives the steel wire rope (8) to run, magnetic energy potential difference information on the steel wire rope (8) is collected, and wire breakage, wear, rust, and fatigue damage of the steel wire rope (8) are quantitatively analyzed and the corresponding data is transmitted to the processor; S4) Before the steel wire rope (8) is put into use, it is fully inspected by a weak magnetic detection device (9) and put into use only after it is found to be free of damage; S5) During the operation of the hoist, when the optical fiber sensor (4) detects that the stress change value of the steel wire rope (8) exceeds a preset threshold value, an alarm is triggered, and the hoist is automatically controlled or manually intervened to stop the load operation, and the hoist is controlled to drive the steel wire rope (8) to move to the weak magnetic detection device (9) for secondary detection.

2. A method for real-time online monitoring of optical fiber weak magnetic bonding of a winding hoist wire rope according to claim 1, characterized in that: The following steps are also included: S6) After the steel wire rope (8) has been in use for a period of time, the weak magnetic detection device (9) is set to a continuous monitoring mode to continuously collect magnetic energy potential difference information on the steel wire rope (8), and perform spatiotemporal correlation analysis on the magnetic characteristic data and the optical fiber stress data through a processor.

3. According to claim 1, a real-time online monitoring method for optical fiber weak magnetic combination of a winding hoist wire rope is characterized in that: The outer surface of the optical fiber cable (3) is sleeved with a flexible protective sleeve (5).

4. A method for real-time online monitoring of optical fiber weak magnetic bonding of a winding hoist wire rope according to claim 3, characterized in that: The outer surface of the protective sleeve (5) is coated with a protective coating (6).

5. A method for real-time online monitoring of optical fiber weak magnetic bonding of a winding hoist wire rope according to claim 4, characterized in that: Fiber strands (7) are arranged on the outside of the protective coating (6), and the rope core (1) of the steel wire rope (8) is arranged on the outside of the fiber strands (7).

6. A method for real-time online monitoring of optical fiber weak magnetic bonding of a winding hoist wire rope according to claim 5, characterized in that: The steel wire rope (8) further comprises a plurality of outer steel wire strands (2) arranged outside the rope core (1).

7. The method for real-time online monitoring of optical fiber weak magnetic bonding of a winding hoist wire rope according to claim 1 is characterized in that: A plurality of weak magnetic detection modules (10) and two groups of wide-angle cameras (11) are arranged inside the weak magnetic detection device (9), and the two groups of wide-angle cameras (11) are respectively arranged at two ends of the plurality of weak magnetic detection modules (10).

8. The method for real-time online monitoring of optical fiber weak magnetic bonding of a winding hoist wire rope according to claim 1 is characterized in that: Two groups of long rods (12) and short rods (13) are respectively arranged on both sides of the outer shell of the weak magnetic detection device (9); a guide wheel (14) is respectively arranged on the long rod (12) and the short rod (13); and the four guide wheels (14) are respectively arranged at the upper and lower ends of both sides of the outer shell of the weak magnetic detection device (9).

9. The method for real-time online monitoring of optical fiber weak magnetic bonding of a winding hoist wire rope according to claim 1, characterized in that: The preset threshold in step S5) includes a dynamic change threshold and a static stress threshold, wherein the dynamic change threshold is when the stress change rate between adjacent sampling periods exceeds 10% / s.

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