October 22, 2014 Burlington, ON

Larry P. Cote l.cote@cinde.ca

Canadian Institute for NDE www.cinde.ca or http://events.cinde.ca

If the Quality goes in, do you need NDT?

Agenda • About the Canadian Institute for NDE

• Terms & definitions

• NDT Techniques for QA/QC, In-service inspection & Condition Monitoring

• Quality & NDT: examples / discussion

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• Non-profit member organization offering: • Approved NRCan training & test center for

CGSB Levels 1, 2 & 3 for MT, PT, UT, RT, ET • Approved CNSC training & test center for

radiography exposure device operators • Professional development courses • Job and resume postings • CINDE Journal published 6 times per year • Annual conference, trade show & job fair

Canadian Institute for NDE www.cinde.ca & http://events.cinde.ca

More tolerable

Broadly

tolerable

Intolerable

RISK

To keep our

tolerance of risk from

the consequences of

failure of:

- Systems

- People

- Equipment & Material

as low as reasonably

practical (ALARP)

* Adapted from IEC 61508-5 Functional safety – Safety-related items 4

Why Quality

or NDT? High

Tolerable Negligible

Risk Spectrum

Moderate

The Product or Equipment Life Cycle

• Specify / Design

• Fabricate / Build

• Sell / Install

• Use / Maintain

• Refurbish / Upgrade

• Replace / retire

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____________________________

What is the Infamous “Bathtub Curve?”

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________________

___

___

___

___

A: B: C:

Failure Modes • A failure has occurred whenever something

cannot perform at the required ____________________________ at the

____________________________ for

___________________________________.

• A failure mode is the absolute and proper understanding of why things fail.

Example: What are some causes of a leaky tire? Is it always the same?

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Failure Consequences

• A failure consequence categorizes the way in which failures matter. There are 5 categories:

H __________________________________

H __________________________________

E __________________________________

O __________________________________

NO _________________________________

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Non-destructive Testing (NDT), Inspection & Evaluation

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Visual Inspection Surface Techniques (MT, PT)

Volumetric Techniques (UT, ET, RT) Flow Monitoring / Strain Gauging

Airborne Ultrasound / Acoustic Emission Vibration Analysis / Infrared Thermography

Assessing the properties, quality or condition of materials or equipment without changing them or causing any damage.

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Let’s think about people as a “data collector” using only our bodies as the “transducer”.

• What can we learn by using our eyes?

• What can we learn by using our ears?

• What can we learn by using our nose?

• What can we learn by using our hands?

• What can we learn by combining ALL of

these sensory inputs together?

Eg. Do we trust Doctors to just look at us to

learn everything about our health?

Or is there some way to extend our natural

senses to see inside things, listen closely for

odd sounds, measure temperature, feel

vibration etc. without touching it?

Visual Inspection

• Simple magnification for closer scrutiny.

• High magnification for microscopic examination.

• Photography for failure analysis and other documentation support.

• High speed video or stroboscope to slow down or “freeze” moving objects for viewing.

• Surveillance cameras for remote or isolated areas.

• Fiber-optic or borescope for unsafe or inaccessible places.

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Visual Inspection to identify ____________ from __________________________________

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Visual Inspection with Strobescope for “stop-action” inspection of moving objects.

A flashing light source is

adjusted to coincide with the

speed of a moving object.

Great for determining the speed

and checking condition of belts,

pulleys and shafts.

For demonstration of inspections

assisted with a strobe light visit: • http://www.youtube.com/watch?v=MqLwgisyjjw&

NR=1&feature=endscreen

• http://www.youtube.com/watch?v=oCvP3LhRFRc

• http://www.youtube.com/watch?v=hZU91uMrOFE

&feature=related

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Visual Inspection – High Speed Video • Capture and analyse transient events not visible

to the naked eye: shifting, shaking etc.

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NDT - Surface Techniques

• Magnetic Particle Inspection

• Liquid Penetrant Inspection

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Magnetic Particle (MT) Inspection

Crane Hook cracked due to ______________

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Fluorescent, Wet Particle Method

Failure modes from interpretation of indications:

Aircraft control arm cracked due to ______________________________________

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Liquid Penetrant Method

Liquid Penetrant Testing

NDT – Volumetric Techniques • Ultrasound

– Pulse / echo

– Airborne

– Flow monitoring

– Acoustic emission

• Eddy Current

• Radiography

• Infrared Thermography

• Vibration Analysis

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Ultrasound – Internal crack detection on Turbine Blades

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Ultrasound (UT) rail subsurface crack detection

Ultrasonic Flow Monitoring

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Doppler or Transit Time for rate of flow in fluid conductors.

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NDT Monitoring – Airborne Ultrasonics (AUT)

What is the purpose of the

ear muffs?

Airborne Ultrasound Bearing being lubricated

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For another demonstration visit:

http://www.youtube.com/watch?v=8QlO8PW6hnA&feature=related

Acoustic Emission Applications • Highly loaded structures and equipment such as

pressure vessels, bridges, bearings and gears that are subject to “creep” due to material fatigue.

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For a demo of Acoustic Emission used for pre-stressed concrete pipe visit:

http://www.youtube.com/watch?v=7N_ozHv1qDk&feature=related

Eddy Current Testing

1. Coil

2. Magnetic

field

3. Eddy

currents

4. Eddy current

magnetic field Conductive material

Radiography (X-ray or Gamma)

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Thermography – Turbine Blade Thickness

So … if the Quality goes in, do you need NDT?

Premise 1: Quality mitigates defects, Reliability mitigates failures. Premise 2: Use quality tools for Quality Improvement & Control. Use NDT inspection and monitoring techniques for Reliability improvement and life extension.

Case History #1 Diesel Generator Shaft Failure

Author: Keith Graeme, Lloyds Registrar

POWER-GEN International 2011, Las Vegas, U.S.A.

• Initial problem & prognosis

• Root Cause Failure Analysis

• Root Cause Solution

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Case History #1 Initial problem

Failure of the main shaft of a

18 cylinder engine driving a

generator.

32 K. Graeme, Lloyds Registrar; POWER-GEN International 2011, Las Vegas, U.S.A.

Case History #1 Initial problem

Main shaft of a 18 cylinder 4-stroke engine driving a generator.

A crack initiated “in a weak spot”, through to catastrophic fatigue failure.

33 K. Graeme, Lloyds Registrar; POWER-GEN International 2011, Las Vegas, U.S.A.

Case History #1 Initial diagnosis / prognosis

• Without further investigation the most likely cause was deemed “material failure”, and a new shaft was installed.

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• Subsequent causes included: – Material defect

– Misfiring

– Alignment

– Structural resonances in the base skid

– Torsional damper malfunction.

K. Graeme, Lloyds Registrar; POWER-GEN International 2011, Las Vegas, U.S.A.

• It failed shortly after.

Case History #1 Root Cause

• inspection of the torsional damper revealed it looked brand new without any damage.

• The moveable parts were locked in position, therefore no damping!

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Actual cause:

• Design / manufacture: – Tolerances too tight.

– Assembly procedure.

– Poor QA/QC of final assembly.

K. Graeme, Lloyds Registrar; POWER-GEN International 2011, Las Vegas, U.S.A.

Case History #1 Root Cause Solution

• Practice changes made to: – Improve assembly

procedures

– Increase clearances to proper tolerance

– Better inspection for proper movement of damper assembly.

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• After modification the engine was taken into operation without any new failures occurring

Author K. Graeme, Lloyds Registrar; POWER-GEN International 2011, Las Vegas, U.S.A.

Case History #2 Shock Absorber Tube Failure

Author: E. P. Papadakais, ASNT Materials Evaluation 2001, Columbus, OH.

• Initial problem & prognosis

• Root Cause Failure Analysis

• Root Cause Solution

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Case History #2 Initial problem

Shock absorber tubes ruptured while in a paint tank at a seam ”that was supposed to be removed” by a previous turning operation.

38 E. P. Papadakis, MATER EVAL, 58(4), 2000, pp. 529-530

Chemical Shock

Absorber

Case History #2 Initial diagnosis / prognosis

• Rod blanks were turned down to eliminate seams that could become cracks during rod blank extrusion into tubes.

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• Installed an Eddy Current inspection system to detect

cracks in shock tubes.

• Cracks might exist but not be visible.

E. P. Papadakis, MATER EVAL, 58(4), 2000, pp. 529-530

• Rod tubes still ruptured in the painting line. (!!)

Case History #2 Root Cause

• The inspection system detected all cracks in test specimens.

• When tested at the manufacturing process, the inspection system found all cracks.

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• Actual cause: – With continued use, the

ET transducer slipped on the shaft.

– Became misaligned with the shock tube blanks

– Some cracks went undetected.

– Defective shock tubes with cracks were installed

E. P. Papadakis, MATER EVAL, 58(4), 2000, pp. 529-530

Case History #2 Root Cause Solution

• Counter bore added for a set screw to keep the ET sensor aligned with tubes.

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• After modification the inspection system reliably detected cracks in rod tubes.

• No more shock tube ruptures occurred in the paint line.

E. P. Papadakis, MATER EVAL, 58(4), 2000, pp. 529-530

If the Quality goes in, do you need NDT? Of course!

• “Defects” affect the initial acceptance and end-use characteristics of materials, equipment and products.

• “Failures” affect service life of equipment and manufacturing processes.

• QA/QC and NDT both reduce the risk from the consequences of failure.

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If the Quality goes in, do you need NDT?

Larry P. Cote l.cote@cinde.ca

Canadian Institute for NDE www.cinde.ca or http://events.cinde.ca

Questions? Thank you!