In magnetic particle inspection (MT/MPI), a flaw becomes visible only if the part carries a magnetic field in the right direction and at sufficient strength, and if the bath and lighting are right. If the bench ammeter reads wrong or the UV-A lamp has weakened, a crack can be missed even when the inspection “passes”. MPI benches and lines therefore need the periodic checks called for by standards such as ASTM E1444, ASTM E709 and the ISO 9934 series.
Scope of calibration and verification
- Current (ammeter) verification: comparing the bench reading with a calibrated reference measuring system at several settings on head shot and coil circuits
- Timer check: verifying magnetising time
- Quick break check: on three-phase full-wave rectified systems, for transverse flaws near part ends
- Magnetic field strength: field measurement with a gaussmeter / teslameter and verification of field direction and adequacy with field indicators (QQI, pie gauge)
- UV-A intensity and ambient light: UV-A intensity and visible light in the darkened area for fluorescent inspection
- Bath checks: guidance on particle concentration (settling test) and contamination
- Demagnetisation check: measuring residual magnetism after inspection
Which equipment?
Horizontal wet benches, automated and semi-automated MPI lines, demagnetising tunnels and portable MPI power units. See Magnetic Particle Inspection, automated MPI lines and industrial demagnetisation systems.
Why it matters
- Records required in customer and certification audits are ready.
- Missed flaws and returned parts caused by wrong current or weak UV are avoided.
- Burning, excessive background and wasted energy from running more current than needed are reduced.
For faults found during calibration we provide technical service. Our other calibration service: online UT system calibration.
Service request: send the make, model and serial number of your equipment, the last calibration date and what you need through our contact form or to info@nexsen.com.tr, and we will come back with a schedule and a quotation.