Contact rod based magnetic particle inspection device and method

Abstract

The invention provides a contact rod based magnetic particle inspection device. The device comprises a handle, two contact rods connected onto the handle and a coaxial aluminium alloy cable. An embodiment of the invention further provides a magnetic particle inspection method based on the contact rods 12. The method comprises steps as follows:division of square partition frames, identification of contacts, adjustment of polar distance, spraying of a magnetic suspension, primary magnetic inspection and secondary magnetic inspection. With adoption of the contact rod based magnetic particle inspection device and method, two times of operation in the same direction and four times of magnetic inspection operation can be realized simultaneously, the labor efficiency is doubled as compared with the prior art, an effective overlapped area is formed by magnetized areas, and an effective magnetized area is enlarged to 150 mm*150 mm.

Description

technical field [0001] The invention relates to the technical field of workpiece non-destructive testing flaw detection, in particular to a probe magnetic particle flaw detection device and a probe magnetic particle flaw detection method. Background technique [0002] Probe method is a commonly used method of magnetic particle flaw detection. According to the American ASTM standard, the distance L between two prods is generally controlled at 75-200mm, but the shortest should not be less than 75mm. [0003] When testing large steel castings, partitions are required. The general requirement is 150mm×150mm area 30. The partitions should be uniform, otherwise it will affect the magnetization of the workpiece and cause some defects to be missed. [0004] In the prior art, the magnetization of the contact rod method is to use a contact rod to induce the circumferential magnetic field alone for magnetization, and the magnetization intensity range after two mutually perpendicular di...

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Problems solved by technology

[0004] In the prior art, the magnetization of the contact rod method is to use a contact rod to induce the circumferential magnetic field alone for magnetization, and the magnetization intensity range after two mutually perpendicular directions of magnetization is as follows: Figure 5 As shown, due to the excessive magnetization current density near the electrodes, it is easy to produce non-correlated display, so there is a detection invalid area in the range of 25mm around the contact, and the effective width of magnetization is 1 / 4 pole pitch, and the overlapping area detected from two directions is Magnetization effective area 31, the area is only 75mm×75mm

[0005] In the actual operation of this method, since there are only two magnetizations perpendicular to each other in each partition and there is a certain range of magnetization ineffective areas near the contacts, the effective range of magnetization in each partition is small, the work efficiency is low, and the magnetization is effective. Regions do not overlap

[0006] At the same time, the cable connecting the flaw detector and the probe is usually made of metal copper core wire with high density. Lifting the probe for a long time consumes the physical strength of the operator, the labor intensity is high, and the magnetization operation is inconvenient.

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