阅读说明：本技术 一种线缆无损检测 (Cable nondestructive test ) 是由 付乐伟 于 2019-10-31 设计创作，主要内容包括：本发明属于线缆无损检测领域,尤其涉及一种线缆无损检测,主要由励磁组件、和漏磁场信号采集传输组件组成,能够有效检测线缆的安全指标和使用寿命的预测是非常有必要的,对企业和施工工人具有较大的经济效益和社会效益。(The invention belongs to the field of cable nondestructive testing, and particularly relates to cable nondestructive testing which mainly comprises an excitation assembly and a leakage magnetic field signal acquisition and transmission assembly, can effectively detect the safety index of a cable, is very necessary for predicting the service life, and has great economic and social benefits for enterprises and construction workers.)

1. A cable nondestructive test comprises an excitation assembly and a leakage magnetic field signal acquisition and transmission assembly, and is characterized in that the excitation assembly adopts a permanent magnet magnetization method and takes a permanent magnet as an excitation source; the permanent magnet is made of iron-iron shed materials and low-carbon steel Q235.

2. The nondestructive testing device for cables as claimed in claim 1, wherein the excitation assembly comprises three sets of permanent magnets comprising three sets of left, middle and right magnetic poles.

3. The XX of claim 2, wherein three groups of permanent magnets form two separate excitation intervals with the magnetic shoe, and different grades of magnets are used.

Technical Field

The invention belongs to the field of cable nondestructive testing, and particularly relates to cable nondestructive testing.

Background

The cable plays an important role in the construction hoisting process and also is an important cable for guaranteeing the life safety of construction workers. The cable is generally manufactured by twisting high-carbon steel wires on a core wire and twisting the wires during assembly, and has the characteristics of good flexibility, high strength, good toughness, light dead weight, high elasticity and the like, is stable and reliable in work, has strong capacity of bearing dynamic load and overload, and is widely used. However, the number of accidents caused by cable breakage is not large every year, so that it is very necessary to provide a prediction for effectively detecting the safety index and service life of the cable, and the method has great economic and social benefits for enterprises and construction workers.

Disclosure of Invention

The invention aims to provide a method for effectively detecting the safety index and the service life of a cable

In order to achieve the purpose, the invention adopts the following technical scheme.

The utility model provides a cable nondestructive test, mainly comprises excitation assembly and leakage magnetic field signal acquisition transmission assembly, and leakage magnetic field signal acquisition transmission assembly gathers wire rope's leakage magnetic signal and sends and carries out signal off-line analysis and processing for outside computer: the excitation assembly provides an excitation source for the steel wire rope: the electromagnetic shielding assembly can prevent the excitation assembly from generating electromagnetic interference on other equipment, and can also prevent the other equipment from generating electromagnetic interference on the steel wire rope nondestructive testing device: the excitation assembly is arranged in the electromagnetic shielding assembly, and the leakage magnetic field signal acquisition and transmission module and the excitation assembly are arranged at intervals.

The excitation assembly adopts a permanent magnet magnetization method, and a permanent magnet is used as an excitation source. Compared with the direct current excitation method, the method is inconvenient for adjusting the excitation intensity. However, the rare earth permanent magnet has the characteristics of high magnetic energy product, small volume, light weight, no need of a power supply and the like, so that the detection instrument adopting permanent magnet excitation has the characteristics of small volume, light weight and the like. Meanwhile, compared with direct current excitation, the excitation structure is simple, so that the use is convenient and flexible. At present, the permanent magnet material is made of iron-iron shed material, and the permanent magnet made of the material is the permanent magnet with the strongest magnetic force at present. In the permanent magnetic structure, a soft magnetic material is indispensable, and plays a role in reducing the magnetic resistance and guiding the magnetic field in the structure. The soft magnetic material is generally selected from electrician pure iron or low carbon steel, and the invention adopts low carbon steel Q235 as the soft magnetic material.

At present, most of common nondestructive testing devices in the market are single-stage excitation structures, namely, the nondestructive testing devices are composed of magnets and magnetic shoes which are arranged according to a certain rule by a left group of magnetic poles and a right group of magnetic poles. The structure is mature, the application is wide, but the excitation intensity is single, the excitation intensity is greatly influenced by external factors, and the verification is difficult.

Therefore, the invention adopts a two-stage excitation structure with innovative design, namely, the two-stage excitation structure consists of iron shed magnets and magnetic shoes, wherein the iron shed magnets are arranged by a left group of magnetic poles, a middle group of magnetic poles and a right group of magnetic poles according to a certain rule, and three groups of permanent magnets are formed. Wherein, form two independent excitation intervals between three groups of permanent magnets and the magnetic shoe to adopt different trade mark magnet. Therefore, the steel wire rope can obtain different magnetic induction strengths in the two excitation intervals, and then a leakage magnetic field with different strengths is generated in a deep saturation state, so that a foundation is provided for subsequent damage identification. The two-stage excitation structure comprises a magnetic shoe (soft magnetic material) and an iron shed magnet. Meanwhile, in order to prevent the permanent magnet from rotating along the central shaft due to the repulsion of magnetic poles, the two ends of the permanent magnet are additionally provided with check blocks which are fixedly connected with the magnetic shoes through bolts.

The designed novel two-stage excitation structure mainly verifies the theoretical feasibility of the novel two-stage excitation structure, and aims at the influence of two factors, namely the distance between permanent magnets and the grade of the permanent magnets in the excitation structure on the excitation effect, the Solidworks software is utilized to establish an excitation structure simplified model, the ANSYSMAXwell software is utilized to carry out three-dimensional static magnetic field finite element analysis on the excitation effect of the novel two-stage excitation structure, and then excitation structure parameters are determined, and theoretical basis is provided for design and manufacture of a nondestructive testing device.

Maxwell3D is an important component of ANSYS electromagnetic field analysis software, and has the advantages of accurate result and easy use. The module mainly comprises resolvers of an electric field, a static magnetic field, an eddy current field, a transient field and the like, and is widely applied to the field of analyzing the electromagnetic characteristics of devices such as motors, sensors, transformers, permanent magnetic equipment, exciters and the like. The three-dimensional static magnetic field solver in Maxwell3D can calculate the magnetic field intensity and current distribution of the simulation object, and the magnetic flux density can be obtained by calculating the magnetic field intensity. The user interface of Maxwell3D is executed from top to bottom, the user can define the material library by himself, and the self-adaptive meshing technology included in the software can help the user to divide the meshes quickly, reasonably and intelligently. The Maxwell3D contains a high-performance matrix solver, and can make full use of computer resources by means of multi-CPU computing processing capacity, so that the computer resources can be rapidly solved.

The beneficial effects are that: the prediction of effectively detecting the safety index and the service life of the cable is very necessary, and the method has great economic and social benefits for enterprises and construction workers.

Detailed Description

The invention is described in detail below with reference to specific embodiments.

The specific implementation mode is as follows:

the utility model provides a cable nondestructive test, mainly comprises excitation assembly and leakage magnetic field signal acquisition transmission assembly, and leakage magnetic field signal acquisition transmission assembly gathers wire rope's leakage magnetic signal and sends and carries out signal off-line analysis and processing for outside computer: the excitation assembly provides an excitation source for the steel wire rope: the electromagnetic shielding assembly can prevent the excitation assembly from generating electromagnetic interference on other equipment, and can also prevent the other equipment from generating electromagnetic interference on the steel wire rope nondestructive testing device: the excitation assembly is arranged in the electromagnetic shielding assembly, and the leakage magnetic field signal acquisition and transmission module and the excitation assembly are arranged at intervals.

The excitation assembly adopts a permanent magnet magnetization method, and a permanent magnet is used as an excitation source. Compared with the direct current excitation method, the method is inconvenient for adjusting the excitation intensity. However, the rare earth permanent magnet has the characteristics of high magnetic energy product, small volume, light weight, no need of a power supply and the like, so that the detection instrument adopting permanent magnet excitation has the characteristics of small volume, light weight and the like. Meanwhile, compared with direct current excitation, the excitation structure is simple, so that the use is convenient and flexible. At present, the permanent magnet material is made of iron-iron shed material, and the permanent magnet made of the material is the permanent magnet with the strongest magnetic force at present. In the permanent magnetic structure, a soft magnetic material is indispensable, and plays a role in reducing the magnetic resistance and guiding the magnetic field in the structure. The soft magnetic material is generally selected from electrician pure iron or low carbon steel, and the invention adopts low carbon steel Q235 as the soft magnetic material.

At present, most of common nondestructive testing devices in the market are single-stage excitation structures, namely, the nondestructive testing devices are composed of magnets and magnetic shoes which are arranged according to a certain rule by a left group of magnetic poles and a right group of magnetic poles. The structure is mature, the application is wide, but the excitation intensity is single, the excitation intensity is greatly influenced by external factors, and the verification is difficult.

Therefore, the invention adopts a two-stage excitation structure with innovative design, namely, the two-stage excitation structure consists of iron shed magnets and magnetic shoes, wherein the iron shed magnets are arranged by a left group of magnetic poles, a middle group of magnetic poles and a right group of magnetic poles according to a certain rule, and three groups of permanent magnets are formed. Wherein, form two independent excitation intervals between three groups of permanent magnets and the magnetic shoe to adopt different trade mark magnet. Therefore, the steel wire rope can obtain different magnetic induction strengths in the two excitation intervals, and then a leakage magnetic field with different strengths is generated in a deep saturation state, so that a foundation is provided for subsequent damage identification. The two-stage excitation structure comprises a magnetic shoe (soft magnetic material) and an iron shed magnet. Meanwhile, in order to prevent the permanent magnet from rotating along the central shaft due to the repulsion of magnetic poles, the two ends of the permanent magnet are additionally provided with check blocks which are fixedly connected with the magnetic shoes through bolts.

The designed novel two-stage excitation structure mainly verifies the theoretical feasibility of the novel two-stage excitation structure, and aims at the influence of two factors, namely the distance between permanent magnets and the grade of the permanent magnets in the excitation structure on the excitation effect, the Solidworks software is utilized to establish an excitation structure simplified model, the ANSYSMAXwell software is utilized to carry out three-dimensional static magnetic field finite element analysis on the excitation effect of the novel two-stage excitation structure, and then excitation structure parameters are determined, and theoretical basis is provided for design and manufacture of a nondestructive testing device.

Maxwell3D is an important component of ANSYS electromagnetic field analysis software, and has the advantages of accurate result and easy use. The module mainly comprises resolvers of an electric field, a static magnetic field, an eddy current field, a transient field and the like, and is widely applied to the field of analyzing the electromagnetic characteristics of devices such as motors, sensors, transformers, permanent magnetic equipment, exciters and the like. The three-dimensional static magnetic field solver in Maxwell3D can calculate the magnetic field intensity and current distribution of the simulation object, and the magnetic flux density can be obtained by calculating the magnetic field intensity. The user interface of Maxwell3D is executed from top to bottom, the user can define the material library by himself, and the self-adaptive meshing technology included in the software can help the user to divide the meshes quickly, reasonably and intelligently. The Maxwell3D contains a high-performance matrix solver, and can make full use of computer resources by means of multi-CPU computing processing capacity, so that the computer resources can be rapidly solved.

ANSYSMAXwell software adopts a finite element method which is used as a numerical solution with the widest application, and the advantages of wide application range and strong universality are well recognized. However, the cell size and the cell distribution density of the mesh directly determine the calculation accuracy of the finite element method, and under normal conditions, the calculation accuracy of the division number of the cell mesh is positively correlated.

In summary, ANSYSMaxwell software is used for mainly solving the problem that a permanent magnet is used as an excitation source, analyzing the magnetic field intensity distribution condition of a steel wire rope in an exciter, obtaining the excitation intensity change rule of the steel wire rope, and providing reference for the excitation structure design of the nondestructive testing device. Therefore, the simulation calculation is mainly carried out by using a three-dimensional static magnetic field solver in Maxwell 3D.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the protection scope of the present invention, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.