Also known as: MT, MPI, magnetic particle testing, magnetic particle examination.
How it works
A magnetic field is induced in the part. Where a crack cuts the flux lines, the field leaks out of the surface and holds the particles applied to it, drawing an indication that is wider than the crack itself and easy to see, especially with fluorescent particles under UV light. Field strength and direction are verified with indicators such as a pie gauge or shims.
Where it is used
Welds in structural steel, pressure equipment and pipelines, machined components, lifting equipment, castings and forgings. It is fast, cheap and works through thin coatings, which makes it the default surface method on steel; liquid penetrant is used instead on non-magnetic materials.
MPI in AMPS
The AMPS AI report assistant is illustrated on an MPI report: the note “MPI on 2 welds, they comply” was rewritten as “Magnetic Particle Inspection conducted on two circumferential welds confirms compliance with ASME B31.3 standards”. In AMPS, reports are produced from your own Microsoft Word templates through the template engine: job data such as the client, purchase order number, equipment serial numbers, location and dates is filled in automatically, an AI assistant can tidy the wording, the report can be signed in AMPS, and the finished Word file is saved in the job’s report folder in your OneDrive, SharePoint or Google Drive.