Special equipment refers to boilers, pressure vessels (including gas cylinders, the same below), pressure pipes, elevators, lifting machinery, passenger ropeways, large amusement facilities and special motor vehicles in the field (factory) which are related to life safety and great danger. Among them, boilers, pressure vessels (including gas cylinders) and pressure pipelines belong to pressure-bearing special equipment; Elevator, hoisting machinery, passenger ropeway and large amusement facilities belong to electromechanical special equipment. 20 14 1 1, AQSIQ announced the newly revised catalogue of special equipment.
Non-destructive testing refers to the analysis of the structure, nature and state of the interior and surface of the specimen, as well as the types, nature, quantity, shape, location and size of defects, with the help of modern technology and equipment and through physical or chemical methods, on the premise of not destroying or affecting the use performance of the detected object and not hurting the internal organization of the detected object. Non-destructive testing is an indispensable and effective tool for industrial development, which reflects the industrial development level of a country to some extent. The importance of nondestructive testing has been recognized, including radiographic testing (RT), ultrasonic testing (UT), magnetic particle testing (MT) and liquid penetrant testing (PT). Other nondestructive testing methods include eddy current testing (ECT), acoustic emission testing (AE), thermal imaging/infrared (TIR), leakage testing (LT), alternating magnetic field measurement technology (ACFMT), magnetic flux leakage testing (MFL), far-field testing (RFT), ultrasonic diffraction time difference method (TOFD) and so on.