1. Ultrasonic inspection: Ultrasonic inspection is a method to detect defects by using the characteristics of ultrasonic wave propagation in materials. The ultrasonic probe contacts the surface of the detected steel structure, emits ultrasonic waves, receives its reflected waves and transmitted waves, analyzes the propagation time and intensity changes of the waves, and determines the position, size and shape of the defects in the material.
2.X-ray inspection: X-ray inspection is a method to detect internal defects by using the ability of rays to penetrate materials. By aiming the ray source at the detected steel structure, the ray penetrates the material and forms an image on the film or detector. By analyzing the image, the position, shape and size of the defect can be determined. X-ray inspection is suitable for thick steel or dense steel, and can detect cracks, inclusions, pores and other defects.
3. Magnetic particle detection: Magnetic particle detection is a method to detect defects on and near the surface of materials by using magnetic fields and magnetic particles. By applying a magnetic field to the surface of the detected steel structure, magnetic particles are adsorbed on the defects, forming magnetic particle traces, and the position, shape and size of the defects can be determined by observing the magnetic particle traces.
Characteristics of nondestructive testing of steel structures;
1. NDT: The biggest feature of NDT for steel structure is that it does not damage the detected object, which means that the integrity of steel structure can still be maintained after the test is completed. This feature enables nondestructive testing to be carried out without affecting the function and subsequent use of components, and is suitable for safety evaluation and maintenance of various important structures.
2. Flexibility and universality: nondestructive testing methods can be flexibly applied to different stages and different parts of steel structures, which can be used for sampling inspection of a single part and comprehensive inspection of the whole structure. Different nondestructive testing technologies such as radiographic testing, ultrasonic testing and magnetic particle testing can be used for mutual verification or supplementary testing of the same part.
3. Dynamic monitoring capability: Non-destructive testing technology can reflect the changes of the internal state of steel structures in real time, such as fatigue cracks, corrosion and other problems that may occur with the changes of stress, environmental conditions and other factors, so as to realize dynamic monitoring of structural health and help to take timely maintenance measures.
Refer to the above content: Baidu Encyclopedia-Steel Structure