Page 250 - CITS - Welder - Trade Theory

WELDER - CITS

Fig 1

Magnetic particle Test(MPT) Principal, advantage,

Limitation., Types of Magnetation, Current requirement,

Testing equipment, indication and interpretation.

Objectives : At the end of this lesson you shall be able to
• describe the principal MPI test.
• explain the MPI advantage and limitation.
• explain the equipments of MPI.

Magnetic particle test: This test is used to detect surface defects as well as sub-surface (up to 6 mm depth)
defects in ferrous materials. A liquid containing iron powder is first sprayed over the joint to be tested. When this
test piece is magnetised, the iron particles will gather at the edges of the defect (crack or flaw) and can be seen
as dark hair line marks with naked eyes.

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CITS : C G & M - Welder - Lesson 83 - 97