The phase angle difference in eddy current testing usually refers to the difference between the phase angle of the surface defect of the tested tube and the phase angle of the through-hole signal under a certain excitation frequency. The bigger the phase angle difference is, the stronger the detection system can distinguish the surface defects from the internal defects, and the stronger the ability to suppress the vibration interference in the inspection of the pipe. It can be seen that the magnitude of phase angle difference reflects the performance of the detection system, which is the pursuit of most eddy current equipment manufacturers.

Eddy current flaw detection of eddy current flaw detector is a kind of flaw detection method which uses electromagnetic induction principle to detect surface and near surface defects of conductive components. The principle is that the eddy current is generated in the conductive component by the excitation coil, and the change of eddy current is measured by the detection coil, so as to obtain the information about the defect of the component. According to the shape of the detection coil, it can be divided into three types: through type (used for wire, bar and pipe detection), probe type (used for local detection of component surface) and insertion type (used for internal detection of tube hole).

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It is usually difficult to clean sucker rods, especially in winter. Oil contamination is often left in the probe during sucker rod inspection, which leads to the decrease of detection accuracy. To solve this problem, our company has successfully developed an "external open" high sensitivity magnetic flux leakage detection probe for sucker rods by adjusting the magnetization structure and magnetization mode. Because of the external and open design of the probe, it brings great convenience to the cleaning and maintenance of the probe, and can be cleaned regularly, thus ensuring the detection accuracy.

Non-standard automation equipment is a kind of non-standard automation equipment customized according to customer requirements. It is designed and customized according to the process requirements of enterprise users. Its operation is convenient, flexible and not single. Its functions can be added according to user requirements. It has great room for modification. It is often used in industry, electronics and medical treatment. Health, and other fields.

Eddy current flaw detector is a compact, multi-functional, practical and cost-effective instrument. Portable battery-powered eddy current testing instrument with excellent performance is suitable for maintenance testing or other eddy current testing. Eddy current flaw detector has good interface and high sensitivity to small cracks and other defects. Its testing probe does not need to touch the tested object, but also can check the conductor with complex shape and size. The eddy current flaw detector needs little preparation in advance, but the test results are real-time.

There are many factors affecting the eddy current field, such as the coupling degree between the probe coil and the tested material, the shape and size of the material, conductivity, permeability, and defects, etc. Therefore, the eddy current principle can be used to solve the problems of metal material flaw detection, thickness measurement and sorting.

Eddy current flaw detection is a defect of alternating current electromagnetic coil in metal plane layer, which is not convenient to use in complex shape components. In thermal power plants, it is mainly used to detect condenser tubes, turbine blades, turbine rotor central holes and welds. Principle When AC is fed into the coil, if the voltage and frequency used remain unchanged, the current through the coil will also remain unchanged. If a metal tube is placed in the coil, the circumferential current, or eddy current, is induced on the surface of the tube.