Magnetic Particle (MT) Method

TM 1-1520-265-23 Change 2 1-27 WARNING Temperatures in excess of 49_C (120_F) may cause bursting of pressurized cans and injury to personnel. e. Store all pressurized spray cans in a cool, dry area protected from direct sunlight. Avoid exposure of pressurized spray cans to open flame. WARNING Volatile fumes may occur, creating both a fire and a health hazard. f. Exercise extreme caution when handling penetrants that have been heated to a point where some lighter constituents are driven off. 1.4.7.2 Controlling Excess Fluorescent Penetrant. After fluorescent penetrant inspection, the part shall be thoroughly cleaned to ensure all excess penetrant is removed from the part. This shall include removing the penetrant from cracks as much as possible before disposition of the part. This can be easily accomplished by performing cleaning operations under a black light. 1.4.8 Magnetic Particle (MT) Method. NOTE Magnetic particle inspection shall be performed in accordance with the general application and techniques in TM 1-1500-335-23 (Nondestructive Inspection methods manual) and the specific requirements of this technical manual. NOTE During magnetic particle inspections performed with portable equipment, the operator shall keep the can of magnetic particle media constantly agitated by continuously shaking the can prior to application. Magnetic particle is a method of detecting cracks or other flaws on the surface or near the surface of materials that are ferromagnetic. This method will produce good indications of discontinuities, provided the part is free from grease, oil, loose scale, or other surface contaminants. The inspection is accomplished on either assembled or disassembled parts. As specified in the procedure, the inspection is accomplished by inducing a magnetic field in the part and applying a liquid suspension of iron oxide particles to the surface to be inspected. By controlling the direction of the magnetic flux, the lines of magnetic force shall be positioned perpendicular to the crack or flaw. All magnetic particle inspections in this manual shall be of the wet continuous method using fluorescent magnetic particles.