Do you know the two main types of inspections for pressure vessels?

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Two main categories of inspection: Pressure vessel inspection can be divided into two main categories: destructive (testing) inspection and non-destructive (testing) inspection. The choice of test and inspection methods should be determined comprehensively based on the production process, technical requirements, and relevant standards and specifications. Destructive (testing) inspections include mechanical property tests, chemical property tests, metallographic tests, weldability tests, and other tests. 1) Mechanical property tests. The quality and specifications of the materials used for pressure vessels shall comply with the corresponding **standards and industry standards. Common tests include tensile testing, bending testing, impact testing, and mechanical property testing of welded joints. In mechanical property tests during pressure vessel inspection, hardness testing is commonly used to indirectly evaluate the mechanical properties of materials as well as the uniformity of these properties. 2) Chemical property tests, metallographic tests, and weldability tests. Chemical composition analysis and metallographic structure inspection of materials and welded joints are commonly used methods in the inspection of pressure vessels. The main purpose of chemical analysis is to determine whether the material meets the specified standards and whether any changes occur after prolonged use. The main purpose of metallographic inspection is to determine whether the microstructural properties of the material in pressure vessels have changed as a result of factors such as temperature, medium, and stress after they are in operation. 3) Other tests: ① Stress testing. For stress analysis of pressure vessels, two methods are commonly used: theoretical analysis and experimental stress analysis. The purpose is to perform strength verification or to draw stress distribution curves. The test methods can determine the actual stress state at various surface or internal points of a pressure vessel after it is loaded. Currently, the electrical resistance strain measurement method is widely used. ②Fracture analysis refers to a technique in which people examine the fracture surface of metal materials or metal components after they have been damaged, either with the naked eye or using instruments, in order to understand the cause of such damage. Fracture analysis is an important part of fracture theory research and a crucial tool for analyzing fracture accidents. The main purposes of fracture analysis are: first, based on non-destructive testing, to determine the nature of various typical defects, thereby providing accurate information for safety analysis and the formulation of reasonable repair plans ； Second, it is to examine the changes in some serious defects during the use of pressure vessels. Non-destructive (testing) inspections include macroscopic inspection, pressure testing, leak testing, and non-destructive testing, etc. Macroscopic inspection can further be divided into visual inspection and inspection using measuring instruments. 1) Visual inspection. It mainly relies on the sensory organs of inspectors and operators to examine the inner and outer surfaces of pressure vessels in order to determine whether there are any defects. Visual inspection allows for the detection of relatively obvious defects on these surfaces, providing clues and a basis for conducting more detailed inspections using other methods. 2) Gauge inspection. Instrument inspection involves using simple tools and measuring devices to determine and measure the defects identified through visual inspection, in order to assess the severity of those defects. It serves as a complement to visual inspection, providing preliminary data for more detailed examinations; it is also the most fundamental basis for accurately judging the defects in pressure vessels. 3) Withstand voltage test. The pressure test, also known as the hydrostatic test and pneumatic test, is a comprehensive verification test. It is not only a test that must be carried out during the final acceptance of a product, but it is also a key item in both internal and external inspections. The main purpose of the pressure test is to evaluate the capacity of pressure vessels to withstand static pressure.