Why is nondestructive testing so important in industry?

Date：2021-09-07 14:00:20Views：1052

Nondestructive testing technology, i.e. non-destructive testing, is the inspection and testing method used to obtain the content, property or composition data related to the quality of the object to be tested with physical or chemical information without damaging or affecting the service performance and chemical properties of the object to be tested. X-ray nondestructive testing technology has made a great contribution to improving the efficiency and quality of industrial casting production process. Common tests include dimensional inspection, visual inspection of surface quality of shape and appearance. In addition to chemical composition analysis and mechanical property test, nondestructive testing is also required. Both are completed in different inspection items according to design requirements or casting process requirements. These inspections increase the cost of cast products.

Therefore, from the beginning, it is necessary to determine the inspection workload required for quality control, especially mass production. According to the actual situation, in some cases, the casting can pass the casting inspection. In other samples, sampling inspection can be carried out, especially for non-destructive inspection of large castings, and important parts can also be inspected, without non-destructive inspection of the whole volume. In short, meet the quality requirements of the design or requirements.

The principle of X-ray flaw detector is to use X-ray to penetrate materials to find object defects and attenuation characteristics of different materials. Using the difference of X-ray absorption of different material thicknesses, through X-ray fluoroscopy and real-time imaging of industrial TV, various parts and welding, films and imaging, cracks and pores in the casting can be clearly displayed, and the contents that can be observed by the naked eye. Defects such as loose objects and internal structures. Evaluate the quality of workpieces and parts according to the nature, size and location of defects to prevent major quality accidents due to internal defects and poor processing.

At present, X-ray flaw detector is widely used. In addition to ordinary portable flaw detectors, X-ray flaw detectors also have many large equipment, which can be used to inspect iron, aluminum castings, automobile parts, pipelines, etc. Due to the limitations of equipment conditions and technical level, most photography techniques have been applied in early X-ray examination. This method is not only expensive and slow, but also the test results are timely and dynamic inspection is not intuitive. In recent years, with the progress of science and technology, the X-ray inspection equipment used in production has become more strict. Castings are also used for industrial parts such as crankshaft, cylinder and engine blade. The production of castings is prone to problems such as bubbles, which can not be solved by traditional technology.

With the change of design concept and the continuous emergence of new high-strength, fatigue and corrosion-resistant materials, NDT itself is facing complex tested objects and test data. After the exploration of human civilization, the basic principle of X-ray image formation is due to the characteristics of X-ray and the difference of component density and thickness. At present, X-ray detection equipment can image in real time, which greatly improves the detection efficiency. When X-ray is applied to the industrial field, if a workpiece has local defects in the production process, the perception of X-ray in the defective place will change, resulting in the change of transmitted light intensity. In this way, using a certain detection method, we can judge whether the workpiece has defects, as well as the location and size of defects.

With the development of modern science and technology, human beings are no longer satisfied with understanding the world from the appearance. With the emergence of industrial CT, a comprehensive testing equipment integrating the knowledge systems of physics and chemistry, quality testing is widely used in the fields of casting, welding process defect detection, industry, lithium battery and electronic semiconductor. Thickness measurement can be used for online, real-time and non-contact thickness measurement. Dynamic research can be used to study dynamic processes, such as trajectory, explosion, nuclear technology and casting technology.