Inspections magnetic particle

Due to the well known human shortcomings the probability of finding flaws using Magnetic Particle Inspection (MPI) or Liquid Penetrant Inspection (LPI) can be restricted to only 60-85% and the inspection reproducablity is difficult. 

Magnetic Particle inspection Liquid Penetrant Inspection... 

Magnetic Particle Inspection was developed by Professor AW de Forest in 1928. De Forest and Doane started the company Magnaflux, the name of which became synonymous with MPI. 

For pipelines in service in chemical plants, it is not usually convenient to place a radiation source inside the pipe and position it to irradiate each welded joint. The radioisotope source container maybe placed on the outer surface of the pipe. The radiation beams then pass through two pipe wall thicknesses to expose films placed diametrically opposite the radiation source, also on the outside of the pipe wall. Other methods, such as magnetic particle inspection of welds in steel pipe, or ultrasonic inspection of welds in pipes of all materials, supplement x-rays in many critical appHcations. The ultrasonic tests can often detect the thin, laminar discontinuities parallel to the pipe surface or the incomplete fusion discontinuities along the weld... 

Corrosion-fatigue cracks can be detected by nondestructive testing techniques such as magnetic particle inspection, radiography, ultrasonics, and dye penetrant. Corrosion-fatigue cracks may occur in numerous tubes simultaneously. Nondestructive testing of tubes at locations similar to those in which cracks are observed can be useftil. 

Identification. Incomplete fusion generally results in discontinuities along the side walls of a joint. When these discontinuities emerge at surfaces, they can be observed visually if accessible (Figs. 15.10 and 15.11). Defects of this type may also be detected by ultrasonics, radiography, magnetic particle inspection, and eddy-current testing. 

Periodically, based on drilling conditions and experience, a magnetic particle inspection should be performed using a wet fluorescent and black light method. 

Magnetic particle inspection for cracks should be made if there is evidence of stretching or swelling. Check box and pin threaded area, especially last engaged thread. 

Figure 4-476. Principle of magnetic particle inspection. (From Ref. [220].)...

Magnetic particle inspection. Surface emergent and some sub-surface cracking can be detected in ferromagnetic materials. The technique must be used on the side of the material in contact with the corrodent. 

Description Conventional wet fluorescent AC yoke magnetic particle inspection used for detection of cracks at a surface. Blending the welds and sanding smooth increases sensitivity. Polish and etch as in a creep evaluation looking for microscopic damage. Replicas can be taken for laboratory analysis. Conventional radiography used to inspect welds for cracks. Internal visual inspection of pressure vessels for surface blistering. Monitors the sound that cracks emit when they are stressed. 

Both wet and dry methods of magnetic particle inspection shall be in accordance with ASTM E709. 

A561 Additional magnetic particle inspection INSP MT c 1 1 lyes (true) Oi no (false)... 

Magnetic Particle Inspection Useful to find surface discontinuities and some discontinuities very near the surface in ferromagnetic materials. More sensitive than liquid penetrant inspection. 

Magnetic particle inspection Section V, Articles 7 and 25 of the AS ME Code Section VIII, Division 1, Appendix 6 of the ASME Code Section VIII, Division 1, Appendix 7, of the ASME Code... 

Wet fluorescent magnetic particle inspection of the remaining journal fillets on this crankshaft revealed the presence of a number of secondary cracks in the same orientation and position as the failure initiation site. A metallographic specimen, including the matching halves of the fracture from the initiation site in the fillet of main journal, was cut, mounted, polished and etched in 2% nital, in preparation for examination with an optical microscope. The polished and etched specimen is shown in Figure 7.44. 

Fig. 6 Environmentally assisted cracking of a weld in a deaerator, caused by a combination of static residual and cyclic operating stresses, and revealed by magnetic particle inspection.

Hydrogen cracks are normally very fine and difficult to detect, even when they break the surface, which they often do not. For cracks which are present at the surface, magnetic particle inspection (MPI) is the preferred technique, although dye penetrant should be used if a non-ferritic filler (e.g. an austenitic stainless steel or a nickel alloy) has been used. The MPI technique has the advantage that when using DC, cracks just below the surface can be detected. 

MAGNETIC PARTICLE INSPECTION - A nondestructive method of inspection for determining the extent of surface cracks and simiiar imperfection in ferromagnetic materiais. 

In assessing the suitability of the winder s drums for an increased load or for continued use, the type of construction as well as the presence of any stress-induced defects need to be taken into account. To this end, both visual examination and Non Destructive Testing (NDT), employing Magnetic Particle Inspection (MPI) methods are implemented. An experienced winder engineer will have a good idea of what to expect to find in a winder s drums that have seen many years of service and very often, the decision as to whether it will be economically... 

The magnetic-particle inspection is performed both before and after threading of the studs. 

Upon completion of all post-weld heat treatments, the reactor vessel is hydrostatically tested, and all accessible ferritic weld surfaces, including those used to repair material, are 1 magnetic-particle inspected in accordance with Section III of the ASME Boiler and Pressure Vessel Code. 

Initial hydrostatic tests of the primary and secondary sides of the steam generator were conducted in accordance with ASME Code, Section III. Leak tests were also performed. Following satisfactory performance of the hydrostatic tests, magnetic-particle inspections are made on all accessible welds. 

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