Magnaflux Universal SW Series Operating Manual

Contents

Magnaflux Universal SW Series Operating Manual Manual pdf 33 page image

10.3 INSPECTION PROCEDURESMeasuring magnetising field strengthThe intensity and characteristics of the magnetic fieldare important parameters for magnetic particle inspec-tion. Always check the magnetisation when setting upthe machine for new workpieces.The FSM-2 is used to measure tangential magneticfield strength. The field strength is displayed in A/cmas both actual (effective) and peak values. For moreinformation about the FSM-2, please see our ProductData Sheet.Tangential magnetic field strength meter FSM-2Procedure1. Magnetise the workpiece.2. Place measuring probe on the workpiece.3. Read the value of tangential magnetic field strengthfrom the display (in A/cm).Checking the concentration of test liquidThe detection of faults in workpieces becomes lessreliable the longer the magnetic particles are in use,as its quality deteriorates over time. The lifespan ofmagnetic powders and liquids depends on the actualtesting environment and the properties of the work-pieces. Check your test liquid regularly and replace itwhen necessary.Optimal detection of cracks depends on the concen-tration of the test liquid. The concentration must cor-respond exactly with the manufacturer’s instructions.Check the concentration after changing the test liquidand after long interruptions in your testing operations.ASTM centrifuge tubeProcedure with ASTM centrifuge tube1. Fill centrifuge tube with test liquid.2. Wait 30 minutes.3. Check the number of graduation marks.NOTE: in systems where the magnetic particle suspen-sion is kept in pumping cycles, do NOT use a centri-fuge tube, as dirt particles in the test liquid can affectthe result.Reference Block 1Left: display capability of test liquid is OKRight: test liquid is exhausted and needs replacingProcedure with Reference Block 11. Spray the test liquid evenly onto the referenceblock.2. Hold the block at the edge and examine under UVlight.3. Compare the display of cracks with the illustrationsin the reference block manual.30