In the process of manufacturing and use of petrochemical forgings, cracks, inclusions and other defects often occur for various reasons, which will seriously affect the performance and service life of the forgings. In order to ensure the safety and stability of petrochemical production, it is very necessary to carry out quality inspection of forgings. Among them, magnetic particle detection technology is a common non-destructive testing method, which has the advantages of fast detection speed and high sensitivity, and is widely used in the defect detection of petrochemical forgings.
Magnetic particle testing technology is a non-destructive testing method that uses the interaction of magnetic field and magnetic particle to detect surface and near-surface defects of materials. The basic principle is that a magnetic field is applied to the material being tested, and if there is a defect in the material, a leakage magnetic field will be formed at the defect. Under the action of the leakage magnetic field, the magnetic powder will be adsorb at the defect, forming a visible magnetic mark, thus showing the position and shape of the defect.
Application of magnetic particle detection technology for petrochemical forgings
Preparation before testing: Clean the tested petrochemical forgings to remove impurities such as oil and rust on the surface. At the same time, the appropriate magnetic powder and magnetic suspension are selected to ensure that the particle size, color of magnetic powder and the concentration and viscosity of magnetic suspension meet the detection requirements.
Magnetization process: The appropriate magnetization method is used to magnetize the forgings being tested. The commonly used magnetization methods are electromagnetic induction method, permanent magnet method, AC electromagnetic method and so on. When choosing the magnetization method, factors such as the shape, size and material of the forging need to be considered.
Applying magnetic powder: After magnetization is complete, the magnetic suspension is sprayed or applied to the surface of the forging. If there is a defect in the forging, the magnetic powder will be adsorb at the defect, forming a visible magnetic mark.
Observation and recording: After applying magnetic powder, it is necessary to observe the distribution and shape of magnetic marks on the surface of the forging to determine the type and severity of defects. At the same time, magnetic marks need to be recorded and analyzed using equipment such as cameras or magnifying glasses.
Post-processing and evaluation: Based on the observed magnetic mark information, the defects of the forging are assessed and classified. For serious defects, it is necessary to repair or scrap; For minor defects, it can be repaired or continued use. At the same time, the test results need to be recorded and archived for follow-up tracking and management.
Ensure that the quality and performance of magnetic powder and magnetic suspension meet the testing requirements, and avoid using expired or deteriorated magnetic powder and magnetic suspension.
During the magnetization process, the magnetic field strength and direction need to be controlled to avoid over-magnetization or under-magnetization.
When applying magnetic powder, it is necessary to ensure that the magnetic suspension is evenly applied on the surface of the forging to avoid the situation of missing or reapplying.
When observing and analyzing magnetic marks, it is necessary to make a comprehensive judgment based on factors such as material, manufacturing process and use environment of forgings.
For the detection of complex shapes or large forgings, segmented detection or multi-angle detection methods can be used to ensure the comprehensiveness and accuracy of the detection.
The magnetic particle detection technology of petrochemical forgings is an effective non-destructive testing method, which has the advantages of fast detection speed and high sensitivity, and is widely used in the defect detection of petrochemical forgings. In the process of application, attention should be paid to the control of magnetic field intensity and direction, the selection of suitable magnetic powder and magnetic suspension, and the guarantee of uniform coating. In the future, with the continuous development and progress of non-destructive testing technology, the magnetic particle testing technology of petrochemical forgings will face more challenges and opportunities. Relevant enterprises and researchers need to constantly explore and innovate to adapt to changes in market demand and contribute to the sustainable development of the petrochemical industry.
