The Magnaflux Y-6 is a portable AC electromagnetic yoke designed to induce a strong localized magnetic field in ferromagnetic test pieces — the first step in magnetic particle inspection (MPI), one of the most widely used non-destructive testing methods for detecting surface-breaking discontinuities in welds, castings, forgings, and structural steel. When the yoke is positioned straddling the inspection area at right angles to the suspected crack orientation and energized, magnetic particles applied to the surface are drawn to any flux leakage caused by a surface discontinuity, forming a visible indication. The Y-6's lift strength exceeds 10 lb (4.5 kg) — beyond the ASTM minimum — confirming sufficient field strength for reliable inspection.

What distinguishes AC yoke inspection from DC yoke methods?

AC magnetization concentrates the magnetic field at the material surface due to the skin effect, making the Y-6 specifically effective for detecting surface-breaking cracks — the most critical defect type for fatigue and service-induced failures. DC yokes penetrate deeper and can detect near-surface discontinuities, but surface sensitivity is reduced. For field weld inspection, in-service crack detection on structures, and spot checks where surface defects are the primary concern, the AC Y-6 provides maximum sensitivity without the weight and power requirements of a DC magnet. The AC waveform also enables demagnetization after inspection: the operator simply holds the yoke energized and slowly withdraws it from the part surface over approximately 18 inches (45 cm).

How does the Y-6 adapt to different inspection geometries?

The double-jointed articulated legs adjust continuously from 2.0 to 11.0 inches (5.1–27.9 cm) between pole centers, accommodating flat plate, curved vessel walls, pipe circumferential welds, and irregular castings without changing accessories. Each leg contact face measures 1.0 × 1.0 inch (25.4 × 25.4 mm) for stable positioning on narrow weld beads. The 12-foot (3.7 m) strain-relieved power cord with integral ground provides sufficient reach for scaffold and confined-space work. The sealed, chemical-resistant housing withstands the oil, grease, and solvent exposure common in maintenance inspection environments, and the 25% duty cycle (90 seconds maximum on-time) supports continuous inspection workflow with adequate cooling between energization cycles.