Western Instruments permanent magnet yokes are portable magnetizing units designed for use in magnetic particle inspection (MPI/MT). Because they utilize rare earth magnets, they require no power or charging , making them particularly suitable for field work, pipe inspection, welds and other demanding work areas. The series includes models such as the WM-5, WM-5LT, WM-5C and LP-5C.

Key features and benefits

• No external power – permanent magnet means the yoke is ready to use without charging or a power cable.

• Strong magnetization – models deliver field strengths typically exceeding 9,000 gauss (on contact) for some models, providing solid lifting power (typically > 50 lbs / ~23 kg).

• Portable and robust – Easy to take to inspection deserts, pipelines or production workshops. The series has variants in both “frame” (hinged) and cable type.

• Flexible use in confined spaces – the LP-5C model in particular is low profile and designed for complex structures and difficult access.

• Certified documentation – Many models come with a calibration certificate and manual, so they fit into quality systems and certification requirements.

Technical specifications

• Western Instruments WM-5 : Lifting capacity > 50 lbs (~23 kg), field strength approx. 9,200 gauss at 2 mm distance. Weight approx. 2.3 kg.

• WM-5LT : Lightweight version, lifting capacity still >50 lbs, field strength approx. 8,500 gauss. Weight approx. 1.4 kg.

• WM-5C : Cable type permanent magnet, field strength approx. 10,900 gauss at contact, and approx. 5,700 gauss at 50 mm distance. Weight approx. 0.9 kg.

• LP-5C : Low-profile cable type for confined work areas. Lifting capacity 50 lbs (tested up to ~85 lbs), height approx. 3.25″ (≈ 8 cm), weight approx. 0.6 kg (490 g). Field strength approx. 10,900 gauss at 2 mm air gap.

• General: Pole spacing varies: for some models up to 24″ (610 mm) as for the WM-5C.

Areas of application

• Surface inspection of welds, pipes and components where magnetic particle method is used to detect cracks and defects.

• Field work and inspection in offshore, oil & gas, steelworks and manufacturing where mobility and ease of use are important.

• Periodic checks of inspection procedures and magnetization equipment – a permanent magnetic yoke allows testing to be performed without additional power infrastructure.

• Situations with tight or hard-to-reach areas where cable-type or low-profile variants offer advantages (for example, LP-5C).

Ask us and we will help you choose the right magnet for your job.