Eddy Current Testing, or ect for short, plays an important role in the field of Nondestructive Testing. Ect testing equipment plays an important role in the field of industrial nondestructive testing. It plays an increasingly important role in aerospace, metallurgy, machinery, power, chemical industry, nuclear energy and other fields.
The main application of ect testing equipment is to detect macroscopic geometric defects on and near the surface of conductive metal materials and to measure thickness of coatings.
According to different characteristics, ect testing equipment can be divided into many different methods:
According to different characteristics, eddy current testing equipment can be divided into many different methods:
(1) According to the form of detection coil:
(a) External penetration type: the tested sample is placed in the coil for testing, which is suitable for the defect of the outer wall of pipes, rods and wires.
B) Inside-through type: Inspection is carried out inside the pipe, specially for inspecting defects in the inner wall of thick-walled pipes or boreholes.
C) Probe type: It can be placed on the surface of the sample for testing, not only for surface scanning of simple-shaped plates, bars and large-diameter pipes, but also for testing of mechanical parts in Fuzhou.
(2) According to the structure of the detection coil:
A) Absolute mode: The coil consists of one coil.
B) Differential mode: consisting of two opposite connected coils.
C) Self-comparison: Multiple coils are wound around a skeleton.
D) Standard comparison: wrapped around two skeletons, one coil is placed in the sample, the other is used for actual testing.
(3) According to the electrical connection of the detection coil:
A) Self-inductance mode: The detection coil uses a winding, which acts as both excitation and detection.
B) Mutual inductance mode: excitation winding and detection winding are separated.
C) Parametric type: The coil itself is an integral part of the circuit.