Magnaflux Y-8 Yoke Magnetic Particle Testing

The Magnaflux Y-8 yoke is a battery-powered, DC electromagnetic yoke designed to stand up to the most rugged applications. Its compact battery pack provides a full 8-hour shift of inspection power, making it ideal for inspection in the field and remote locations.

• Chemical and abrasion resistant
• Exceeds ASTM lifting specifications
• Articulated, double-jointed legs.
• Sealed, durable, lightweight construction.
• True portability with compact battery pack
• Individual serial number on each yoke
• Solid state controls for maximum safety and reliability
• Magnaflux Y-8 yoke

FAQs – Magnetic Yokes (Magnaflux Yoke & MT Inspection Equipment Guide)

What is a magnetic yoke and when is it used?

A magnetic yoke is a portable NDT tool used in magnetic particle testing (MT) to locate surface and slightly subsurface cracking in ferromagnetic materials. Because of their lightweight and versatile design, Magnaflux yokes are widely used for weld inspection, structural steel testing, automotive components, and general NDT inspection work across the UK & Ireland. Their portability makes them ideal for both workshop and on-site testing environments.

What types of yoke does Magnaflux manufacture?

As one of the leading Magnaflux suppliers in the UK, the product range includes:

• Y-2 – ergonomic, lightweight AC magnetic yoke

• Y-6 – durable, lightweight AC electromagnetic yoke

• Y-7 – versatile AC/DC yoke for surface and subsurface defect detection

• Y-8 – battery-powered DC yoke, ideal for field and remote inspections Magnaflux Y-8 yoke

All Magnaflux NDT yokes feature adjustable legs/pole pieces for optimum surface contact during MT inspection.

How can I check the performance of my yoke?

Performance of any NDT yoke can be verified using two recognised methods:

1. Lift test – confirming the yoke can lift the required weight to prove magnetic strength.

2. Field strength measurement – checking the magnetic output between the yoke legs in accordance with DIN EN ISO 9934.

These checks ensure the yoke continues to meet inspection standards for magnetic particle testing.

What is the difference between AC and DC yokes in magnetic particle inspection?

• AC current is preferred for surface crack detection, offering strong surface flux for identifying open-to-surface defects.

• DC or rectified current is used when subsurface defect detection is required, as it produces deeper magnetic penetration.

In real-world environments, results can vary depending on part geometry, temperature, accessibility, defect orientation and the general conditions of the inspection area — a key consideration for weld inspectors working outdoors or on structural steel.

Can I convert an AC yoke to DC?

Yes. Connecting an AC electromagnetic yoke to a 12 V DC battery allows it to generate a DC magnetic field, expanding its capability to highlight deeper defects. This can be a cost-effective way to gain both surface and subsurface testing functionality.

What is the correct orientation for a magnetic yoke when searching for defects?

For the best results during magnetic particle testing, position the yoke so the expected defect direction is perpendicular (90°) to the magnetic field. Correct alignment is critical for generating the flux leakage required to reveal both surface and near-surface flaws.

Are Magnaflux yokes CE marked and certified?

All Magnaflux yokes—with the exception of the Y-7 AC/DC yoke—are CE marked and supplied with the relevant certification. Each unit is produced with a unique serial number for quality assurance and traceability, making them reliable choices for inspectors, fabricators and companies seeking compliant NDT equipment in the UK & Ireland.

View our Magnaflux range of NDT products here

Magnaflux Y-8 yoke  Part number 630550