MF- 43550Y - 7 AC/DC Yoke

The Y-7 is an articulating leg magneticyoke providing A.C. or D.C. magneticfields for defect detection inferromagnetic materials. The Y-7 has thecapability of demagnetization, if required.Please read instructionsbefore using.

MF-43550Y-7 AC/DC YokeInstructions

2007 Goodson Shop Supplies July 2013

Specifications:

Power Source: The Y-7 is configured for115 volt, 50/60Hz.1 phase, OR 220 volt,50 Hz.1 phase.Current Draw: 115V version - 4 amps /230V version - 2 amps.Mechanical Capacity: Minimum-maxi-mum distance across poles: 1 to 12".Magnetic Field: A.C: Constant level.D.C: Pulsed.Pull Force: The Magnaflux Y-7 yoke isdesigned to lift 10 lbs or 40 lbs as speci-fied inASTM E-444. Please refer to this specifi-cation for more details.Yoke Weight: 7.7 pounds.Controls: Electronic - Solid state con-tained within the housing.Manual: Momentary, push to test switchA.C./D.C. selector switchDuty Cycle: 33% with 80 seconds "ON"maximum.Caution!1. DO NOT connect the power cord toa battery for portable work-powersource must be asnoted on the nameplate.2. DO NOT change the AC/DC selectorswitch while the unit is energized.

How to use

1. Preclean inspection area.Spray on CleanerWipe off with acloth

2. Place Yoke onTest pieceperpendicular todirection ofsuspected cracks

3. Energize Yoke.Magnetic field willform in test piece.

4. Apply magneticpowder orprepared bathwhile yoke is ener-gized.

5. Indications willform immediately.

Principle of Operation:

With the instrument connected to a properpower source, depressing the "PUSH toTEST" switch creates an intense magneticfield between the legs. The resultant fieldcan best be described as a multiplicity ofinvisible lines of force extending across thegap between the legs. As the yoke isapplied to a steel plate, the magneticcircuit is closed, and the magnetic fieldenters the plate making its passagebetween the legs of the yoke at and verynear the surface. A surface crack acrossthis field cuts the magnetic circuit;the two sides of the crack becomeopposite poles of a magnet and a leakagefield occurs in the air above the crack.Magnetic particles are attracted by thisleakage, mark its location.Magnetizing Field Selection:A.C. MAGNETIZATION-This induced fieldis a surface field which only detectsindications open to the surface. It isparticularly useful for inspecting thick andirregular sections for surface defects. Goodresults are generally obtained with drypowder method using any of part numbersWCD-.(PULSED) D.C. MAGNETIZATION-Thisinduced field penetrates the work pieceand detects both surface and (slightly)subsurface indications. Good results aregenerally obtained with the wet method.Using Magna - Fluro oil. Butexperimentation with method variablesshould always be practiced.

Operation:Adjust the legs to an appropriate spacingand place the yoke firmly upon the workpiece (securing the best contact possible)with the suspected defect at a right angleto the poles. With the selector switch ineither the AC or the DC position, depressthe test switch to energize the yoke andlightly dust *(dry powder) or flow or spray*(wet method) inspection particles over thearea of interest. As an example, whentesting for longitudinal surface cracks in aweld, the yoke would be positioned so thatthe legs straddle the weld. If the directionof a possible defect is not known, twoinspections should be made in such area,turning the yoke approximately 90 degreesfor the second inspection.Using the powder blower bulb, the areabetween the legs of the yoke is dustedlightly with MAGNAFLUX powder andinspected closely for cracks or otherindications. Current should remain "on"(continuous method). This process isrepeated until the entire area of the part isinspected. Experience with different partsand surfaces will indicate the bestmagnetizing current, particle application,and testing procedures to obtain goodinspection results. The "continuousmethod" should always be used formaximum sensitivity.

** NOTE: ***Not included (Dry Powders, Applicators,and Sprays for Wet Method)Sold separately (See column to the rightfor Order chart)

Demagnetization:The Y-7 yoke can usually be used toobtain satisfactory level ofdemagnetization. With the instrument inthe AC mode, place the part across thepoles and while the current is flowingslowly withdraw the part from the field toa distance of a least 18 before turningoff the magnetizing current.

Magnaflux Powder For dry method magnetic

particle inspectionColor Size Order No.White 1 lb. WCD-100-G

5 lb. WCD-500-G25 lb. WCD-2500-G

Yellow 1 lb. WCD-101-G5 lb. WCD-501-G

25 lb. WCD-2501-GRed 1 lb. WCD-103-G

5 lb. WCD-503-G25 lb. WCD-2503-G

Magna-Fluro OilReliable inspection Oil impregnated with Magnaglo powder (CR-14)

to glow under black-light Low viscosity Flows easily into small cracks Oil clarity makes cracks easier to seeDescription Order No.Aerosol MFA-125 gallon (18.93 liter) MFA-50

*Order part numbers NOTIncludedwith kit.*

Applicators A quick & easy method for distributing Magnaflux powderDescription Order No.Applicator Bulb to cover large areas WCD-266-GAtomizer Assembly for small areas MM-301Replacement Bulb for Atomizer Jar MM-301-1