1. Before measurement, the universal magnetic particle flaw detector should be cleared of all dust and dirt from the surface of the object to be tested, and scrape off any paint or covering materials. Rough surfaces can cause measurement errors in the universal magnetic particle flaw detector, even resulting in no readings.
2. Before measurement, the surface of the material to be inspected should be as smooth as possible with the general-purpose magnetic particle flaw detector. This type of detector can also utilize high-viscosity coupling agents. For measuring cylindrical materials such as pipes and oil drums, it is ideal to align the probe's axis with the material's axis. The general-purpose magnetic particle flaw detector couples the probe with the material to be inspected, then rotates the probe around the material's axis or moves it parallel to the axis perpendicular to the material, with the detector ensuring the probe's delay block's centerline makes contact with the material for accurate thickness measurement.
For different diameters of the test objects: Using different delay blocks for the general-purpose magnetic particle inspection machine can be helpful for measurement. The general-purpose magnetic particle inspection machine can be covered with a fine sandpaper on the surface of the test object and then the probe is moved back and forth. To achieve a satisfactory ultrasonic response, the opposite surface of the test material must be parallel or coaxial with the test surface; otherwise, the general-purpose magnetic particle inspection machine may cause measurement errors or display no readings at all.
4. The thickness of the material for universal magnetic particle inspection machines and the speed of ultrasonic wave propagation are both affected by temperature. When a high measurement accuracy is required for universal magnetic particle inspection machines, the block comparison method can be used to correct the measured values of the inspected workpieces with this coefficient.
5. For materials such as fibers, porous, and coarse-grained materials, they cause significant scattering and energy attenuation of ultrasonic waves, leading to abnormal readings or even no readings on universal magnetic particle inspection equipment. In such cases, it indicates that the material is not suitable for testing with this type of universal magnetic particle inspection machine.
Factors Affecting the Magnetic Particle Inspection Machine's Detection Effect:
1. Magnetic field size and direction 2. Selection of magnetization methods 3. Selection of magnetic particles 4. Concentration of magnetic suspension 5. Equipment functionality 6. Workpiece shape and surface roughness 7. Magnetization time and operation 8. Nature and shape of defects 9. The essence of the flaw detector 10. Lighting conditions