Temperatures in excess of 49 °C (120
°F) may cause bursting of pressurized cans and injury to personnel.
Store all pressurized spray cans in a cool, dry area protected from direct sunlight. Avoid exposure of pressurized
spray cans to open flames.
Volatile fumes may occur, creating both a fire and health hazard.
Exercise extreme caution when handling penetrants that have been heated to a point where some lighter
constituents are driven off.
220.127.116.11 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.
Magnetic particle inspection shall be performed in accordance with the general application and
techniques in TM 55-1500-335-23 (Nondestructive Inspection Methods manual) and the specific
requirements of this technical manual.
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.
18.104.22.168 Magnetic Particle Inspection Equipment. Considerations involved in the selection of magnetic particle inspection
equipment include the type of magnetizing current and the location and nature of the inspection. The purpose of this
manual is to support the accomplishment of NDI at the AVUM and AVIM levels. This dictates equipment that can be
used on or off the helicopter at remote sites. Therefore, magnetic particle procedures in this manual use the
electromagnetic yokes or probes and hand-held coils as shown in Figure 1-6. This equipment is common and readily
available to AVUM and AVIM levels. Stationary magnetic particle equipment can be used if facilities, required shop
equipment, and qualified NDI technicians are available. Refer to TM 55-1500-335-23 (Nondestructive Inspection
Methods manual) for stationary magnetic particle inspection techniques.