uv light inspection for ndt

8/12/2019 Uv Light Inspection for Ndt

1/14

UV LIGHT INSPECTION FOR NDT CRACK DETECTION


2/14

E quipment Required

Ultraviolet Black Light (365nm wavelength) (100 fc at 15 inches)

Fluorescent Iron Particles

Burma Castrol Strips

Magnetizing Coil

Magnetic Field Indicator

Spray Can

Rags

Centrifuge Tube

Centrifuge Tube Stand

Dark Room

Water


3/14


4/14

Demagnetization

A longitudinal magnetic field has magnetic lines of force that run parallel to the long axis of the part.

A circular magnetic field has magnetic lines of force that run circumferentially around the perimeter of a part.

Interpretation of indications

After applying the magnetic field, indications that form must interpreted.This process requires that the inspector

distinguish between relevant and non-relevant indications.

Demagnetization

Parts inspected by the magnetic particle method may sometimes have an objectionable residual magnetic field that may interfere with subsequent manufacturing operations or service of the

component.

Possible reasons for demagnetization include:

May interfere with welding and/or machining operations

Can effect gauges that are sensitive to magnetic fields if placed in close proximity.

Abrasive particles may adhere to components surface and cause and increase in wear to engines components, gears, bearings etc.


5/14

Limitations of

Magnetic Particle Inspection

Cannot inspect non-ferrous materials such as aluminum, magnesium or most stainless steels.

Inspection of large parts may require use of equipment with special power requirements.

Some parts may require removal of coating or plating to achieve desired inspection sensitivity.

Limited subsurface discontinuity detection capabilities. Maximum depth sensitivity is approximately 0.6 (under ideal conditions).

Post cleaning, and post demagnetization is often necessary.

Alignment between magnetic flux and defect is important

PPE Required

Gloves

Ultraviolet Safety Glasses


6/14

Dimensions

Steel Rule

OD Caliper

ID Caliper

Tally Tape

Depth Gauge


7/14


8/14


9/14

Ultrasonic Wall Thickness Measurement

UT Meter

Coupling

Reference

Gauges


10/14


11/14

Visual Welding Inspection

Welding imperfection:

UNDERCUT

POROSITY

INCOMPLETE FUSION

OVERLAP

UNDERFILL

SPATTEREXCESSIVE CONVEXITY

EXCESSIVE CONCAVITY

EXCESSIVE WELD REINFORCEMENT

INCOMPLETE PENETRATION

EXCESSIVE PENETRATION

UNACCEPTABLE

WELD PROFILES


12/14

Visual Thread Inspection

Tool Joints Imperfection

Black Crested Threads

Chattered Threads

Cracks

Cuts

DentsEccentricity

False Starting Threads

Feather Edge

Fin on Threads Crest

Galled ThreadsPitted Threads

Rusted Threads

Threads Profile Out

Interrupted Starting Threads


13/14


14/14

uv light inspection for ndt

Documents