Heat exchangers are devices that transfer part of the heat of a hot fluid to a cold fluid, also known as heat exchangers. Heat exchangers are common equipment for chemical, petroleum, power, food and many other industrial sectors and play an important role in production. In chemical production, heat exchangers can be used as heaters, coolers, condensers, evaporators, reboilers, etc., and are more widely used.
The heat exchange tubes have been exposed to different conditions such as high temperature, high pressure, and corrosion during use. With the prolonged use of the heat exchange tubes, corrosion, cracks, and other defects may occur at different levels. Therefore, the detection of heat exchange tubes in service has become a problem for many chemical companies. Urgent needs.
Eddy Current Detection (ECT) detects non-ferromagnetic tubes in a non-contact manner. This technique is suitable for detecting and quantifying discontinuities such as corrosion, erosion, wear, pitting, baffle cuts, wall thickness loss, and cracks in non-ferrous metal materials.
Both coils are energized by a current to generate a magnetic field around the coil. The magnetic field passes through the tubing material and generates the opposite AC in the material. These currents are called eddy currents.
A.Any defect that changes the eddy current will also change the impedance of the coil in the probe.
B.Measure changes in coil impedance, and use these changes to detect defects in fittings.