Nondestructive testing of metal in Jiangsu
Mr. Wang: 13102238283 (WeChat with the number) QQ:3144667033
Phone: 022-23892103 email: 182@rd-test.com
The workpiece defect magnetic particle interaction and magnetic leakage field, it uses the steel surface and near surface defects (such as cracks, slag, crack etc.) difference of permeability and permeability of the magnetic steel, these materials discontinuity magnetic field distortion will occur, forming part of the magnetic flux leakage at the surface of the workpiece the leakage magnetic field, thereby attracting magnetic powder defect of the powder accumulation of magnetic marks, in the appropriate light conditions, showing the defect position and shape of these particles accumulation to be observed and explained, on the realization of the magnetic particle testing. Magnetic particle inspection is a nondestructive testing method for detecting defects on the surface or near surface of ferromagnetic material by the accumulation of magnetic flux in the magnetic field near the defect. The production of iron and steel workpiece magnetic material to be magnetized, the leakage magnetic adsorption magnetic characteristics of the defects, according to the magnetic distribution display detection method of object surface defect and near surface defects to be detected. The flaw detection method is characterized by simple, intuitive display. Magnetic particle flaw detection and the use of Hall elements, magnetic sensitive semiconductor components of the flaw detection method, the use of magnetic tape recording magnetic flaw detection, the use of coil induction electromotive force detection method belong to the magnetic flaw detection method.
Magnetic particle inspection
The advantages of magnetic particle testing are intuitive, high speed, high sensitivity, and amplification defects.
Magnetic particle inspection
Magnetic particle inspection:
1, according to the different magnetization direction of the workpiece, it can be divided into the circumferential magnetization method, the longitudinal magnetization method, the complex magnetization method and the rotating magnetization method.
2, according to the different magnetization current can be divided into: DC magnetization method, half wave DC magnetization method, and AC magnetization method.
3, according to the detection of magnetic powder used in the preparation of different, can be divided into dry powder and wet powder method.
4, according to the workpiece magnetic time is different, can be divided into continuous method and residual method.
Standard and methods for MT testing of magnetic particle testing
Test standard
JB/T 4730.4-2005 pressure equipment nondestructive testing fourth parts magnetic particle testing
Magnetic particle inspection process
1, pretreatment
2, magnetization
3, the application of magnetic powder or magnetic suspension
4, observation and recording of magnetic marks
5, defect rating
6, after demagnetization.