Yokes - Parker Research

Parker Research was the originator of the flexible-leg magnetic inspection yoke (trade named Contour Probe) and has been manufacturing portable Magnetic Particle Inspection Equipment and accessories for over forty years.

Parker Research offers a great selection of Yokes, Coils, and Portable testers.

Guide to Parker Magnetic Particle Testing Yokes

When purchasing a yoke for magnetic particle inspection, we know that there are many factors to consider. That’s why we’ve provided you with the following guide. We’ve taken each of the most common purchasing considerations and matched them with the Parker yoke (or yokes) that we think suits it best. Of course, we encourage you to browse the subsections below, or call us for more details.

Safety

If the yoke is to be used for Wet Method MPI, or if the user will be standing on a wet surface or with wet hands, he/she should consider purchasing the B-300MR or B-300UF, as they provide the highest degree of electrical safety.

Price

All Parker Research’s yokes are considerably less expensive than other main brands and they are available in more models. The B-100 is the least expensive.

Weight

If the yoke will be held for a considerable length of time, its weight needs to be considered. This is especially important when working vertical and overhead. The P-2 is the lightest at 4.6 pounds.

Physical Size

For inspectors with small hands, the P-2 or B-200 should be considered. They have the smallest grip, at 1 5/8” x 2 1/8”.

On/Off Switch Placement

Top-mounted on/off switches are operated with your thumb, while handle-mounted switches are operated with your forefinger. We have heard that yokes with forefinger control are less tiring when used for a long period of time. UW-12 with handle-mounted switch shown above.

The DA-200 was developed in the 1960’s to meet the AWS requirement to use HWDC for welding inspection. The DA-400 was then developed as a lighter-weight version. These are still the most popular yokes for welding inspection.

Field Strength / Pulling Power

All AC models must be able to lift an excess of 10 lbs and DC models must be able to lift 40 lbs.
When a yoke is used with a long extension cord or the legs are worn, the lifting power will be decreased. Parker AC Yokes are rated 1.5 - 3x so you can be assured that you have many years of service built in to each one. Click Here for a full list of field strength values for each model.
Note: the pull strength listed is for any leg spacing, unlike other brands’ yokes which require a special 10# block to pass the lift requirement.
The A-210 and DA-200 are the largest yokes, have the largest leg spans and are the most powerful.

Maneuverability