Intermediate Infrared Concepts and Best Practices: Thermal Imaging in your Maintenance ProgramSat SandhuThermography Services Support Manager

Thermal / Infrared Thermography, Level III Certified in compliance with (ASNT) SNT-TC-1A-2006

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• Review and introduction to Thermal imaging

• The basics of performing an inspection with an infrared camera

• Tips on how to effectively spot issues with an infrared camera

• Causes and examples of Electrical, Mechanical, Process and Building Diagnostics

• How to tie infrared inspections into your preventative maintenance program

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Agenda

My name is Sat Sandhu Welcome!

Please note, this is a short class – you will not become a thermography expert in the next hour

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Introduction

• Infrared radiation can be sensed by our skin, yet cannot be seen by our eyes!

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What is infrared?

• Infrared cannot be seen (but can be sensed by our skin)

• Everything emits infrared radiation• A camera converts the “infrared

image” to a visible picture• Infrared allows you to “see” things that

you normally can’t

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What is a Thermal Image?

Visual image

Same image in infrared

• Thousands of IR temperature measurements taken• Each “pixel” represents a temperature measurement• Assigned a color value to create an image

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How is an infrared image created?

• Most electrical and mechanical defects cause increase in temperature

• Thermal imaging provides a fast and clear picture of this temperature increase

• Safety: Thermal images can be taken while production is running without any contact

• Anybody can take a picture!

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How can infrared help me?

• Electrical• Mechanical• Process Manufacturing• Building Diagnostics• R&D• Utilities

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Thermal Imaging Applications

• Ensure adequate thermal gradients• Understand thermal capacitance• Account for wind effects• Avoid angular variations• Remember heat transfers from hot to

cold• Be aware of your surroundings• Know when qualitative

measurements are sufficient• Compare similar components under

similar conditions

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Thermal Imaging Considerations

• Understand present and future loading conditions• Inspect with highest load possible (at least 40%)

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Thermal Imaging Considerations

• Objects and materials with high thermal capacitance take time to cool down, while objects and materials with low thermal capacitance cool down quickly

– Air has low thermal capacity, water has high thermal capacity

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Heat Capacity

On a flat roof, after the sun goes down, dry insulation cools faster than wet insulation

(wet insulation has higher thermal capacity)Thermal capacitance can help find

the liquid level in a tank

How far can I see?

Distance from CameraL1 M4

L1 M4

Spot Size & Resolution

• Larger area for average temperature when further away

• Distance to spot ratio• Zoom lens decreases

spot size

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Spot Size & Resolution

• Emissivity • Understand the equipment• Load conditions• Comparative inspections• Hot spots• Cold spots

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TIPS: How to Effectively Spot Issues with an Infrared Camera

This can of suds is ice cold straight out of the fridge.  When scanned with the IR Camera you would expect the entire image to be relatively even in temperature and to appear “cold” in relation to the background.  What is causing the spot in the center to appear warm?

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What happened to my beer!?

Everything in nature emits electromagnetic radiation. Emissivity is the ratio of thermal energy emission of the target object, over the thermal energy emission of a true blackbody (perfect emitter).

The paint on the outside of this can has been worn off in a small area.  The bare aluminum has a different emissivity than the painted aluminum. The imager sees the bare aluminum as hotter than the rest of the can.

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Emissivity!

TIP: Use Electrical Tape to cover a low emissive surface to increase the emissivity and accuracy of the measurement

• Unbalanced loads• Harmonics (3rd harmonic current in

Neutral)• Overloaded systems/excessive

current• Loose or corroded connections

increased resistance in the circuit • Insulation failure• Component failure• Wiring mistakes• Underspecified components

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Causes of Electrical Hot Spots

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Examples of Electrical Hot SpotsHot phase

Fuse disconnect

Substation

Lighting Circuit

Motor Control Center

Buss

• Bad cooling because of reduced airflow• PQ problems like unbalance, overload or 5th harmonic (voltage) • Insulation problems with motor windings• Bearing problems – lubrication, wear, tolerance• Bad alignment

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Causes of Mechanical Hot Spots

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Examples of Mechanical Hot Spots

Compressors - normal

Hydraulic pumps Misaligned beltElectric motor

Roller bearingsCoupling

• Damaged structures caused by worn pipes• Abnormal heat flow/heat gradients• Defective valves/traps• Normal tank level fluctuations

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Causes of Process Hot Spots

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Examples of Process Hot Spots

Weld cooling

Tank Levels

119.7°C

302.2°C

150

200

250

300

Steam TrapsCement Kiln

Pipe IntegrityChiller Operation

• Roof leaks• Air Leak• In-floor heating• Missing insulation

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Causes of Building Diagnostics Hot Spots

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Examples of Building Diagnostics Hot Spots

Roof deck moisture

In-floor heat verification

Missing insulationMoisture

Air Leak Attic access – air leak

• Trends

• Maintenance programs

• Cost Savings

• Solutions

• Build a Successful program

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How to Tie Infrared Inspections into your Preventative Maintenance Program

Downtime is getting more expensive – maintenance must do more with less

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Trends in Industrial Maintenance

Companies are using maintenance best practices to reinforce and extend their competitive advantages

Awareness is growing quickly

New maintenance technologies are experiencing mass adoption

ECONOMICS AWARENESS TECHNOLOGY

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Definitions

Preventive (PM):

“calendar-based”

Predictive (PdM): “condition-based”

Time

Normal Operation Wear OutBreak In

The Bathtub Curve

Casualties

Reactive: “run to failure”

Proactive

Reliability Centered: “asset uptime based”

1. EPRI – study of many plants in many different industries•A comprehensive study by the Electric Power Research Institute found:

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Examples of Cost Savings

Maintenance practices

Cost to maintain rotating machinery

Cost savings

Plants that are Reactive (Run to failure)

$17/HP/Year No savings

Plants that are Preventive (Calendar-based)

$13/HP/Year 24% over Reactive

Plants that are Predictive (Condition-based)

$9/HP/Year 47% over Reactive

2. Cost to Benefit Studies•A large company implemented a Predictive Maintenance program on hundreds of their motors, pumps, fans, compressors and blowers•This program has been successful for over 25 years•They document the cost of the program and savings they enjoy•Savings were many millions of dollars per year•Every 2 years they conduct a Cost to Benefit study to compare the program cost to the documented savings•The average Cost to Benefit ratio for the past 30 years has been over 20:1

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Examples of Cost Savings

The 6 benefits that they track include: •Prevention of catastrophic failure due to early detection•Ability to schedule repairs during plant shutdown periods•Ability to order parts in advance of repairs•Ability to repair exact fault instead of complete overhaul or replacement•Planning of workers schedules•Root cause analysis of recurring faults

3. Case Study – even small companies can benefit

•Over a 16 year period, a small company transitioned from Reactive to Preventive and then to Predictive Maintenance:

– Unplanned failures dropped to almost zero– Maintenance budget, on the 600 critical motor/pumps, cut in half

from 10 years ago– Pumps running twice as long before repairs are needed– Almost all maintenance is scheduled instead of reacting to

emergencies– Repairs planned during the day and eliminating the need for

overtime

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Examples of Cost Savings

• Predictability: give maintenance staff time to schedule repairs

• Safety: take faulty equipment offline

• Revenue: fewer unexpected failures prevent production stoppages that cut into bottom line

• Increased maintenance intervals: life of equipment is extended

• Reliability: anticipate the problems coming

• Peace of mind: build confidence in maintenance schedules, budgeting, and productivity estimates

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Benefits of Proactive Maintenance

Different industries / companies will have different matrixes and targets. Which of these benefits is most valuable to you?

• Ideal: Dedicated PdM or reliability team at a large industrial plant

– People, time and budget to do proactive work

– Uses automated systems/CMMS

– Determines when equipment needs maintenance to prevent failure

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Solution: Asset Uptime for the Rest of Us

Technology is leveling the playing field for maintenance technicians across facilities of all sizes: they can use the same techniques and tools to troubleshoot

as well as to inspect, log, and share – the basics of proactive maintenance

• The rest of us: Small maintenance team at mid-sized industrial or large commercial facility with

– No dedicated people – Broad responsibilities but not

the scope or budget to go full SCADA

– Gather data by hand as the job dictates

Don’t try to do the whole plant at once•Start with simple machines with common problems•Use simple check lists before moving to electronic programs•Show success in early wins, gain buy-in and support to grow program•Proactive maintenance measurements aren’t that different from troubleshooting tests – only faster, easier, and no expert is needed

Simple steps•Take “good” baseline data points – compare over time to good baseline•Quick periodic inspections with screening tools to find problems•Return with smart diagnostic tools – find fault and diagnose repair action•Repair fault with smart corrective tools – fix it quickly & return to service•Validate repair with screening tool

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Program Start-up: Start Small and Grow

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Basic Inspection Guideline

Schedule inspection under load

Thermal Image

Any Anomaly

observed?

Equipment on or

Loaded?

Equipment on or

Loaded?

Equipment on or

Loaded?

Temperatures on target, similar to each other, and

c/f with ambient?

Temp. difference c/f stds.

Identify the type of anomaly:1.Hot spot?2.Cold Spot?3.Temp. difference between similar components?

No Further Action

Extra info / Advice

process

Repair / Action

No

Yes

Yes

No Low

Low

Low

High

High

HighHigh

Low

Medium

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A Program Builds the Links in a Maintenance Chain

Multiple tools equal more than the sum of the parts

Alignment Tool

Problem corrected

Vibration Tester Vibration Tester

Problem identified & repair recommended

Machine checked with vibration meter

Thermal Imager

Problem found with vibration meter

SCAN DIAGNOSE FIX VALIDATE

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Technologies & Solutions – Multiple Tools

Thermography Mechanical Electrical Process

Infrared Imager Vibration and Alignment

ScopeMeter and Power Quality

Insulation Tester

Process Tools

Best technology for finding electrical hot spots in switchgear & motor controllers, screening process and mechanical

Best technology for diagnosing mechanical faults in rotating machines. Correct shaft misalignment.

Troubleshoot problems in drive and drive output, power distribution - uncover energy losses & efficiency

Assures safe operation, prolongs life of electrical systems & motors

Troubleshoot, commission and calibrate transmitters, valves, switches, gauges

1. Faulty connections

2. Overheated bearings

3. Tank levels

1. Imbalance 2. Looseness 3. Misalignment 4. Bearings

1. Harmonics2. Distortion3. Load Studies

Insulation degradation

1. Pressure2. Temperature3. mA source

• I want to see a camera? • I want to learn more about thermal imaging?• I want an IR camera? • I want to talk about my specific application?

• We have 2 certified Level I thermographers on staff– Ben Goodhead– Susan Garofalo

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Before we dismiss…

Questions or Comments?Email Nicole VanWert-Quinzi

nvanwert@Transcat.com

Transcat: 800-800-5001www.Transcat.com

For related product information, go to: www.Transcat.com/Fluke