Magnetic Particle Testing

GB NDT ENGINEERING SERVICESGB NDT ENGINEERING SERVICES LAB E-52, INDUSTRIAL ESTATE,LAB E-52, INDUSTRIAL ESTATE, THUVAKKUDY, TIRUCHIRAPPALLI-620015THUVAKKUDY, TIRUCHIRAPPALLI-620015

MAGNETIC PARTICLEMAGNETIC PARTICLE TESTINGTESTINGPREPAREDPREPARED

BYBY

G.PARAMJOTHI G.PARAMJOTHI BEBE(MECH),(MECH),MBA,MBA,NDT LEVEL IINDT LEVEL II

[ TECHNICAL OFFICER [ TECHNICAL OFFICER // NDT C NDT CO - ORDINATORO - ORDINATOR ] ]

T.C. KARTHIKEYAN T.C. KARTHIKEYAN DME, NDT LEVEL IIDME, NDT LEVEL II

[ TECHNICAL OFFICER][ TECHNICAL OFFICER]

INTRODUCTIONINTRODUCTION

Magnetic Particle Inspection is non-destructive

testing method for detecting the presence of

flaws, cracks, cold shuts, porosity, lack of fusion

and other common faults or discontinuities in

ferromagnetic metallic materials, such as iron and

magnetic alloys of steel. The technique is best

employed for detecting discontinuities that are

open to the surface, and subsurface in material.

PRINCIPLEPRINCIPLE

Flux Leakage at surface.

MAGNATIZATIONMAGNATIZATION Magnetization of certain metals is possible to

reveal the discontinuities by passing a medium of

iron powder having magnetic attraction.

THEORY OF MAGNETIZATIONTHEORY OF MAGNETIZATION

An object is magnetized. When part or all of its

magnetic domains have their north to south pole

attraction is known as Magnetization

PROPERTIES OF MATERIALPROPERTIES OF MATERIAL

• Permeability.

• Reluctance.

• Residual Magnetism.

• Retentivity.

TYPES OF MAGNETIZATIONTYPES OF MAGNETIZATION

• Circular Magnetization. – Prod Method (Dry)– Head Shot Method (Wet) – Central Conductor Method (Wet)

• Longitudinal Magnetization

-Yoke Method ( Dry/Wet )

-Coil Method ( Dry/Wet )

PROD METHODPROD METHOD

HEAD SHOT METHODHEAD SHOT METHOD

CENTRAL CONDUCTOR CENTRAL CONDUCTOR METHODMETHOD

YOKE METHODYOKE METHOD

COIL METHODCOIL METHOD

MT Indications