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|
2002 |
|
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|
February
11, 2002
Sponsored
by:
|
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| |
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| |
Electrical
System Inspections
|
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| |
When performing an electrical
system inspection, don't forget to record electrical
load on the subject circuits. Doing so will not
only enable you to duplicate your inspection efforts
during a follow up inspection but will also allow
you to make meaningful assessments when trending
either absolute temperatures or delta Ts.
Ammeter readings should always
be taken with a true RMS sensing ammeter for accurate
load readings.
|
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|
February
18, 2002
Sponsored
by:
|
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| |
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| |
Electrical
System Inspections
|
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| |
Ambient
temperature is a term which appears in nearly
all thermographic reports. However, many thermographers
define ambient differently. Some define it as
room air temperature while others define it as
the temperature inside of the component enclosure.
According to the IEEE,
for electrical components ambient temperature
is the environmental temperature immediately surrounding
the subject component. For devices located within
enclosures, this is the temperature within the
enclosure while it is closed and operating. For
components in free air, it is the temperature
surrounding the component.
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February
25, 2002
Sponsored
by:
|
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| |
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| |
Steam
Traps
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| |
In
order to increase the accuracy of thermographic
inspections of steam traps, contact ultrasonic
testing should be used as well as infrared imaging.
Contact ultrasonics are much more sensitive to
trap failures than temperature measurement alone.
When
testing traps, begin by using your thermal imager
to ascertain that steam is reaching the trap.
The trap inlet should be above 212 F. Next, listen
to the trap outlet with your ultrasonic unit.
Although traps should cycle periodically, you
should not hear a continuous hissing or rushing
sounds.
While
it takes some practice to become proficient with
ultrasonic testing, the increased accuracy is
worth the effort.
|
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|
March
1, 2002
Sponsored
by:
|
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| |
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| |
Flat
Roofs
|
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| |
When
performing an infrared inspection of low slope
roofs, it is imperative to verify thermal data
with destructive testing. While infrared imagers
can detect temperature changes associated with
missing and damaged insulation, they cannot ascertain
the cause of the thermal image.
Core sampling or invasive
moisture meter readings are the only known methodologies
for accurately determining moisture content. Coupling
invasive verification with thermal imaging not
only improves accuracy of the inspection but also
is required by ASTM Standard C1153.
|
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|
April
1, 2002
Sponsored
by:
|
Sun
Infrared Technologies, Inc.
Chuck
Rolek, President
808 West Lakeshore Drive
O'Fallon, Illinois 62269 |
|
| |
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| |
Referencing
Visual Images
|
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| |
When
doing Thermographic Surveys, often the certified
Thermographer will want to reference the exception
he or she is viewing in the Infrared Image with
an arrow or point in the visual digital image.
By
using either a Laser Pointer or a Pyrometer with
a Laser aiming device, while shooting the picture
the red spot from the laser will show up in the
digital photo and eliminate
the need for a reference arrow in the visual display
photo of the report.
|
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|
April
8, 2002
Sponsored
by:
|
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| |
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|
| |
Infrared
Inspections of Flat Roofs
|
|
| |
Infrared
inspections can be especially helpful in formulating
a roof maintenance program. As with other types
of infrared inspections, several interdependent
factors can affect a thermographer's success.
Before beginning an inspection, there are several
things that one must consider to help ensure accurate
data collection.
1)
Roof Construction: Applicable roof construction
is as follows: Built up or single-ply membrane
installed over, and in continuous contact with,
a layer of insulation or an insulating deck. Roof
may be either smooth, granule or gravel surfaced.
If gravel surfaced, stones should be pea sized
or smaller.
Roofs
covered with concrete pavers or river washed ballast
(walnut sized rock) are not candidates for an
accurate infrared inspection.
Roofs
with thick insulation systems may be difficult
to image when moisture is present only at the
bottom of the insulation layer.
2)
Equipment: For highly reflective and smooth
surfaced roofs , use a short wave (3-5 micron)
imager to overcome reflections caused by nightime
sky. For gravel or granule surfaced roofs, you
may use either a long wave or short wave camera
with good results.
3)
Time of Day: In general, infrared inspections
are best performed at night after a sunny day;
however, there are several environmental factors
which will influence the ability to collect accurate
data. Minimum weather requirements are as follows:
-
Recent rain sufficient to cause wetting of roof
components
-
Dry roof surface at sunrise. No ice, snow or
standing water
-
Mostly sunny day
-
Daytime highs above 40 F
-
Daytime winds of less than 15 mph at the rooftop
-
Nightime winds of less that 15 mph at the rooftop
during IR inspection
-
No rain on day of infrared inspection
4)
Roofing Materials: Some materials are more
difficult to inspect than others. Roofs having
lightweight concrete or gypsum can be more difficult
to inspect because they can retain significant
quantities of moisture either left over from construction
or due to building usage.
For
roofs having an insulation layer, the absorbency
of roof insulation can also affect one's ability
to detect moisture as well as the intensity and
type of thermal patterns observed.
5)
Water Ingress: Not all water that enters a
roofing system will enter the insulation system.
Infrared inspections rely on moisture being absorbed
by roofing system components causing a change
in thermal capacity or thermal conductivity. Should
water bypass the roof insulation, no unusual thermal
patterns will be observed.
6)
Moisture Content: The amount of moisture within
the roofing system will have a direct impact on
the images observed. The clear, well-defined IR
images found in text books are not always found
in the field.
Additionally
, roofs which are completely saturated will not
exhibit clear thermal patterns but will often
exhibit a mottled thermal pattern.
7)
Moisture Verification: To ensure accuracy
all infrared data must be verified through invasive
testing and the results correlated to infrared
data. Remember, an infrared imager is not a moisture
meter.
8)
Experience: Because thermography is an art
as well as a science, an experienced operator
may be able to shed some expertise on difficult
roofs. This is a situation where working with
a mentor can be especially helpful or you may
wish to work with an experienced infrared consultant
who specializes in roof inspections.
For
additional information, you may wish to check
out the following documents:
- ASTM
C-1153 Standard Practice for the Location of
Wet Insulation in Roofing Systems Using Infrared
Imaging
- Infraspection
Institute Guideline for Performing Infrared
Inspections of Building Envelopes and Insulated
Roofs
- For information on training,
contact Infraspection Institute. Our Level I
Certified Infrared Thermographer Course is taught
by field experienced instructors with extensive
knowledge in infrared inspections of flat roofs.
|
 |
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|
April
15, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Infrared
Equipment Cost
|
|
| |
Budgeting for infrared test equipment
can be a daunting task. Prices for infrared test
equipment vary widely depending upon the type
of instrument and equipment features. There are
generally three categories of infrared test equipment:
1) Non-imaging radiometers
2) Thermal imagers
3) Imaging radiometers
Non-imaging
radiometers,
often referred to as infrared pyrometers, point
radiometers or spot radiometers, produce temperature
data by detecting the invisible infrared radiation
emitted by an object and converting this energy
into a temperature value. These temperature values
may be displayed in either analog or digital fashion
in either Celsius or Fahrenheit.
Non-imaging
radiometers may be either hand-held or permanently
mounted for continuous temperature monitoring
or can be integrated with a computer for automatic
process control.
Most
modern, hand-held radiometers employ a laser sighting
system to enable the user to help aim the instrument.
Hand-held radiometers are best suited for taking
non-contact temperatures of stationary electrical
or mechanical equipment at close distances.
Prices
for hand-held non-imaging radiometers range from
$100 to $3000 depending upon features and capabilities.
Permanently-mounted radiometers can range in price
from $1000 to over $100,000.
For
more information on non-imaging radiometers, please
visit: www.irinfo.org/radiometer_mfgrs.html
Thermal
imagers are video camera like devices which
convert invisible infrared radiation emitted by
an object into a monochrome or multi-color image
on a monitor screen wherein the various shades
or colors represent thermal patterns across the
object's surface.
Prices
vary widely for thermal imagers depending upon
features and capabilities.
For
monochrome thermal imagers, prices start at less
that $10,000 for lower resolution systems and
range to over $100,000 for high resolution airborne
systems. Thermal imagers are most often used in
surveillance or in applications where temperature
measurement is not required.
Imaging
Radiometers. Simply put, imaging radiometers
are thermal imagers that can also measure temperatures.
Imaging radiometers have a wide variety of uses
in maintenance, aerospace, research & development,
quality assurance, condition monitoring and forensic
applications.
Once
again prices vary widely depending upon features
and capabilities such as image storage and available
software for post processing of images and data.
Pricing for imaging radiometers begins around
$15,000 and can exceed $50,000 depending upon
how the system is configured.
For more information on thermal imagers and imaging
radiometers, please visit: www.irinfo.org/imager_mfgrs.html
Because
equipment varies widely in its capabilities, it
is imperative that buyers and users of infrared
test equipment fully understand how to properly
choose an instrument for the task at hand.
Lastly,
the greatest limiting factor in an infrared inspection
is the equipment operator. Relying on data by
untrained persons can have disastrous consequences.
To this end, a trained and certified operator
of infrared equipment is of paramount importance
for accurate data collection and interpretation.
For training and certification courses for thermographers,
please visit: www.infraspection.com.
|
 |
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|
|
April
22, 2002
Sponsored
by:
|
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| |
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| |
Infrared
Equipment Calibration
|
|
| |
You
can check infrared imagers and radiometers for
temperature measurement accuracy using blackbody
simulators. To do this you will need two separate
blackbody simulators with known temperatures and
known emittances. The complete procedure takes
very little time and is detailed in Infraspection
Institute's Level II Certified Infrared Thermographer
Reference Manual. In following this procedure
and using a standard reference, you will be calibrating
your IR instrument.
If you prefer not to follow
the above procedure or if determine that your
camera is out of calibration, you will have to
return it to the manufacturer for calibration
adjustment. Unfortunately, there are no independent
laboratories who perform calibration adjustments
since the procedures for doing so are considered
proprietary and are maintained as trade secrets
by infrared equipment manufacturers. As such,
you must return infrared equipment to the manufacturer
for any calibration adjustments.
|
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|
April
29, 2002
Sponsored
by:
|
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| |
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|
| |
Calculating
Infrared Inspection Program Payback
|
|
| |
Calculating
savings and/or avoided costs is one of the most
difficult tasks associated with an infrared inspection
program; however, doing so is required in order
to gauge how effective a program is.
In
short, there is no way to calculate the exact
value of the findings of an infrared inspection
other than allowing the component run to failure
and adding up the subsequent losses. Unfortunately,
this is not a practical approach to maintenance.
As
an alternative, there are several methods that
professionals use to estimate program savings.
A brief description of each of the most common
methods is listed below:
1.
Summary of Findings - A report comprised of
the deficient items found during a given time
period. Reports may be by the day, month, year,
etc. This type of report does not provide any
financial data.
2.
Performance Effectiveness Ratios - Use
accounting data to trend how an infrared inspection
program impacts an overall maintenance program.
Typically calculated for a single facility over
an extended period of time. Improvements in efficiency
can be compared to similar facilities or to the
performance history subject facility.
3.
Avoided Costs Method - A summary of the
estimated cost of repairs for breakdown versus
proactive repair efforts. Typically, proactive
repairs are always cheaper since the outage can
be planned and the cost of the actual repair is
usually less since the subject equipment often
suffers far less damage when not allowed to run
to catastrophic failure.
4.
Permanent Improvement Method - This is
a summary of the financial impact on a given facility
due to the implementation of an infrared inspection
program. For example, infrared can be used to
supplement a maintenance program by directing
repair efforts to only those areas in need of
attention rather than periodic application of
labor-intensive manual work. In such cases, the
cost difference between the two methods results
in a savings every time the manual maintenance
procedure is avoided in the future.
5.
Statistics Based Method - This method is
based upon insurance industry statistics associated
with loss claims that have been paid to clients
over a several year period. This method takes
into account the value of the overall facility
along with the severity of the problem. While
this method is not as accurate as the Avoided
Cost Method, it can be applied quickly and easily
with a minimum of effort. Infraspection Institute's
Exception 2000 software utilizes this method
for calculating savings as one of its standard
features.
Each
of the above methods varies in the information
provided as well as the ease of use and accuracy.
We cover each method in depth in our Level III
Certified Infrared Thermographer Course.
When calculating savings, we
recommend that thermographers consult with their
end user and choose one of the above methods that
will best suit his/her needs and consistently
apply the chosen method over time. While you will
not be able to calculate savings exactly, you
should obtain a good indication of the value of
your program.
|
 |
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|
|
May
6, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Infrared
Inspections of Process Equipment
|
|
| |
Infrared
thermography offers good potential for detecting
energy losses from process equipment and piping
as well as some symptoms of pipe deterioration.
It
is important to remember that thermography is
a line-of-sight technology that detects thermal
patterns and associated temperatures across the
surface of an object.
Subsurface
characteristics or defects cannot be detected
by thermography unless they cause a temperature
differential of at least 0.1 Celsius degrees across
the surface of the object being inspected. Presently,
interior corrosion detection is best detected
with ultrasonic thickness testing; exterior corrosion
may be detected by visual examination.
Thermography
may prove useful if corrosion is being caused
by water saturated insulation surrounding your
process piping. If this is the case, water saturated
insulation should show excess energy loss at the
point where the water is entrapped. It will be
necessary to visually inspect the pipe to confirm
the actual condition of the pipe.
When
performing thermal imaging, be aware that weather
conditions such as solar gain, wind and atmospheric
attenuation can adversely affect your results.
Be certain that your imaging system is capable
of detecting the anticipated defect by understanding
how emissivity, spectral response and spot size
will affect your inspection.
Should you require further
information on thermography or to obtain a course
schedule, please feel free to visit www.infraspection.com.
|
 |
|
|
|
|
May
13, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Imager
Settings for Roof Inspections
|
|
| |
Proper
camera sensitivity is imperative when performing
infrared inspections of low slope roofs. When
performing an infrared inspection it is necessary
to adjust level and gain settings depending upon
the area or roof component being inspected.
In
most cases, base flashings will require lower
or less sensitive settings than the field of the
roof. This is due to the fact that base flashing
areas contain more mass than uninterrupted roof
membrane and will typically radiate more heat
than the open field of the roof.
When
inspecting areas with greater density such as
base flashings, it is important to concentrate
on these areas and to qualitatively compare them
to similar roof details.
|
 |
|
|
|
|
May
18, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Infrared
Inspections of Flat Roofs
|
|
| |
Infrared
inspections can be especially helpful in formulating
a roof maintenance program. As with other types
of infrared inspections, several interdependent
factors can affect a thermographer's success.
Before beginning an inspection, there are several
things that one must consider to help ensure accurate
data collection.
1)
Roof Construction: Applicable roof construction
is as follows: Built up or single-ply membrane
installed over, and in continuous contact with,
a layer of insulation or an insulating deck. Roof
may be either smooth, granule or gravel surfaced.
If gravel surfaced, stones should be pea sized
or smaller.
Roofs covered with concrete pavers
or river washed ballast (walnut sized rock) are
not candidates for an accurate infrared inspection.
Roofs with thick insulation systems
may be difficult to image when moisture is present
only at the bottom of the insulation layer.
2) Equipment: For highly
reflective and smooth surfaced roofs , use a short
wave (3-5 micron) imager to overcome reflections
caused by nightime sky. For gravel or granule
surfaced roofs, you may use either a long wave
or short wave camera with good results.
3) Time of Day: In general,
infrared inspections are best performed at night
after a sunny day; however, there are several
environmental factors which will influence the
ability to collect accurate data. Minimum weather
requirements are as follows:
-
a) Recent rain sufficient to cause wetting of
roof components
- b)
Dry roof surface at sunrise. No ice, snow or
standing water
- c)
Mostly sunny day
- d)
Daytime highs above 40 F
- e)
Daytime winds of less than 15 mph at the rooftop
- f)
Nightime winds of less that 15 mph at the rooftop
during IR inspection
- g)
No rain on day of infrared inspection
4) Roofing Materials:
Some materials are more difficult to inspect than
others. Roofs having lightweight concrete or gypsum
can be more difficult to inspect because they
can retain significant quantities of moisture
either left over from construction or due to building
usage.
For roofs having an insulation
layer, the absorbency of roof insulation can also
affect one's ability to detect moisture as well
as the intensity and type of thermal patterns
observed.
5) Water Ingress: Not
all water that enters a roofing system will enter
the insulation system. Infrared inspections rely
on moisture being absorbed by roofing system components
causing a change in thermal capacity or thermal
conductivity. Should water bypass the roof insulation,
no unusual thermal patterns will be observed.
6) Moisture Content: The
amount of moisture within the roofing system will
have a direct impact on the images observed. The
clear, well-defined IR images found in text books
are not always found in the field.
Additionally , roofs which are
completely saturated will not exhibit clear thermal
patterns but will often exhibit a mottled thermal
pattern.
7) Moisture Verification:
To ensure accuracy all infrared data must
be verified through invasive testing and the results
correlated to infrared data. Remember, an infrared
imager is not a moisture meter.
8) Experience: Because
thermography is an art as well as a science, an
experienced operator may be able to shed some
expertise on difficult roofs. This is a situation
where working with a mentor can be especially
helpful or you may wish to work with an experienced
infrared consultant who specializes in roof inspections.
For additional information, you
may wish to check out the following documents:
- ASTM C-1153 Standard Practice
for the Location of Wet Insulation in Roofing
Systems Using Infrared Imaging
- Infraspection Institute Guideline
for Performing Infrared Inspections of Building
Envelopes and Insulated Roofs
- For information on training,
contact Infraspection Institute. Our Level I
Certified Infrared Thermographer Course is taught
by field experienced instructors with extensive
knowledge in infrared inspections of flat roofs.
|
 |
|
|
|
|
May
27, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Infrared
Inspections of Process Equipment
|
|
| |
Infrared
thermography offers good potential for detecting
energy losses from process equipment and piping
as well as some symptoms of pipe deterioration.
It
is important to remember that thermography is
a line-of-sight technology that detects thermal
patterns and associated temperatures across the
surface of an object.
Subsurface
characteristics or defects cannot be detected
by thermography unless they cause a temperature
differential of at least 0.1 Celsius degrees across
the surface of the object being inspected. Presently,
interior corrosion detection is best detected
with ultrasonic thickness testing; exterior corrosion
may be detected by visual examination.
Thermography
may prove useful if corrosion is being caused
by water saturated insulation surrounding your
process piping. If this is the case, water saturated
insulation should show excess energy loss at the
point where the water is entrapped. It will be
necessary to visually inspect the pipe to confirm
the actual condition of the pipe.
When
performing thermal imaging, be aware that weather
conditions such as solar gain, wind and atmospheric
attenuation can adversely affect your results.
Be certain that your imaging system is capable
of detecting the anticipated defect by understanding
how emissivity, spectral response and spot size
will affect your inspection.
Should you require further
information on thermography or to obtain a course
schedule, please feel free to visit www.infraspection.com.
|
 |
|
|
|
|
June
4, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Infrared
Equipment Cost
|
|
| |
Budgeting
for infrared test equipment can be a daunting
task. Prices for infrared test equipment vary
widely depending upon the type of instrument and
equipment features. There are generally three
categories of infrared test equipment:
1)
Non-imaging radiometers
2) Thermal imagers
3) Imaging radiometers
Non-imaging
radiometers, often referred to as infrared
pyrometers, point radiometers or spot radiometers,
produce temperature data by detecting the invisible
infrared radiation emitted by an object and converting
this energy into a temperature value. These temperature
values may be displayed in either analog or digital
fashion in either Celsius or Fahrenheit.
Non-imaging
radiometers may be either hand-held or permanently
mounted for continuous temperature monitoring
or can be integrated with a computer for automatic
process control.
Most
modern, hand-held radiometers employ a laser sighting
system to enable the user to help aim the instrument.
Hand-held radiometers are best suited for taking
non-contact temperatures of stationary electrical
or mechanical equipment at close distances.
Prices
for hand-held non-imaging radiometers range from
$100 to $3000 depending upon features and capabilities.
Permanently-mounted radiometers can range in price
from $1000 to over $100,000.
For
more information on non-imaging radiometers, please
visit the radiometer
page.
Thermal
Imagers: Thermal imagers are video camera
like devices which convert invisible infrared
radiation emitted by an object into a monochrome
or multi-color image on a monitor screen wherein
the various shades or colors represent thermal
patterns across the object's surface.
Prices
vary widely for thermal imagers depending upon
features and capabilities.
For
monochrome thermal imagers, prices start at less
that $10,000 for lower resolution systems and
range to over $100,000 for high resolution airborne
systems. Thermal imagers are most often used in
surveillance or in applications where temperature
measurement is not required.
Imaging
Radiometers: Simply put, imaging radiometers
are thermal imagers that can also measure temperatures.
Imaging radiometers have a wide variety of uses
in maintenance, aerospace, research & development,
quality assurance, condition monitoring and forensic
applications.
Once
again prices vary widely depending upon features
and capabilities such as image storage and available
software for post processing of images and data.
Pricing for imaging radiometers begins around
$15,000 and can exceed $50,000 depending upon
how the system is configured.
For more information on thermal imagers and imaging
radiometers, please visit the imager
page.
Because
equipment varies widely in its capabilities, it
is imperative that buyers and users of infrared
test equipment fully understand how to properly
choose an instrument for the task at hand.
Lastly,
the greatest limiting factor in an infrared inspection
is the equipment operator. Relying on data by
untrained persons can have disastrous consequences.
To this end, a trained and certified operator
of infrared equipment is of paramount importance
for accurate data collection and interpretation.
For training and certification courses for thermographers,
please visit: www.infraspection.com
|
 |
|
|
|
|
June
10, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Wide Angle Lenses
|
|
| |
Using
a standard lens to perform infrared inspections
at close distances can be particularly difficult.
This situation is quite common when inspecting
motor control centers and some types of mechanical
equipment.
If
you must image from a near distance, you may not
be able to compare your target to an adjacent
reference. For larger targets you may be able
to only see a portion of the target.
Wide
angle lenses increase an imager's visual field
of view allowing a thermographer to image a wider
target area without having to move farther from
the target. Wide angle lenses are available for
most imagers in multipliers of either 2x wide
or 3x wide. Spot measurement
size will increase proportionately to the width
multiplier for the lens.
If you are taking temperatures,
be sure that your wide angle lens has been calibrated
for your imager.
|
 |
|
|
|
|
June
17, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Infrared
Inspections of Building Envelopes
|
|
| |
Many
people think about the heating season and the
thermal performance of their homes and offices.
Thermal imaging can be extremely useful in identifying
areas of excessive heat loss or air leakage. The
effectiveness of an infrared inspection will depend
upon how the inspection is performed.
A common misconception is that
infrared inspections are performed merely by looking
at the exterior surfaces of a building from the
outside of the structure. While this practice
may identify gross defects for some structures,
it usually fails to detect more serious defects
such as air infiltration and heat distribution
problems within the building.
For best results, infrared inspections
of buildings should be performed from the inside
of the building when there is a minimum inside/outside
temperature differential of 10 Celsius (18 F)
degrees for several hours prior to, and during
the inspection. The inspection should include
all exterior walls, windows, doors and ceilings
imaged from the interior of the building. Performing
the inspection on a calm night will eliminate
errors due to solar loading and wind. Additionally,
the building HVAC system should be operated under
normal conditions. For commercial buildings this
may involve overriding the HVAC system controls
to duplicate daytime settings.
If you are concerned about the
thermal performance of your building, the best
time to conduct an infrared inspection is at the
beginning of the heating season. Performing your
inspection now will enable you to make necessary
repairs before the cold weather sets in.
As always, a certified,
experienced thermographer will help to ensure
that you receive accurate and reliable data.
|
 |
|
|
|
|
July
1, 2002
Sponsored
by:
|
 |
|
| |
|
|
| |
Wide
Angle Lenses
|
|
| |
Using
a standard lens to perform infrared inspections
at close distances can be particularly difficult.
This situation is quite common when inspecting
motor control centers and some types of mechanical
equipment.
If you must image from a near
distance, you may not be able to compare your
target to an adjacent reference. For larger targets
you may be able to image only see a portion of
the target.
Wide angle lenses increase an
imagers visual field of view allowing a thermographer
to image a wider target area without having to
move farther from the target. Wide angle lenses
are available for most imagers in multipliers
of either 2x wide or 3x wide. Spot measurement
size will increase proportionately to the width
multiplier for the lens.
If you are taking temperatures,
be sure that your wide angle lens has been calibrated
for your imager.
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July
8, 2002
Sponsored
by:
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Safety
Standards
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Although
thermography has gained wide acceptance for use
in P/PM, Condition Monitoring and Forensics, thermographers
often are unaware of the existence of published
safety standards regarding infrared inspections.
The following is a partial list
of currently distributed safety standards along
with the organizations who publish them. Contact
these organizations directly to obtain copies.
- National Fire Protection Association,
Quincy MA
- NFPA 70E Standard For Electrical
Safety Requirements for Employee
Workplaces
- Occupational Safety and Health
Administration
- 29 CFR Part 1910 Occupational
Safety and Health Standards for General
Industry
- 29 CFR Part 1926 Occupational
Safety and Health Standards for General
Construction
It should be noted that many
workers (miners, transportation, many federal
workers) are exempt from OSHA standards; however,
there are often agencies similar to OSHA who publish
applicable standards for these workers.
Infrared Inspections are often
performed in hazardous environments. Safely conducting
an infrared inspection should be of paramount
importance for all involved. Prior to beginning
an infrared inspection, a thermographer must be
aware of which safety standards apply to his/her
work.
The Infraspection Institute
Level 3 Certified Infrared Thermographer covers
thermographer safety and applicable standards
in depth. For more information, contact Infraspection
Institute at 609-239-4788 or online at www.infraspection.com
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July
15, 2002
Sponsored
by:
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Performance
Standards
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Performance
Standards and Specifications for Thermography
Although thermography has gained
wide acceptance for use in P/PM, Condition Monitoring
and Forensics, thermographers often are unaware
of the existence of published standards and specifications
regarding infrared inspections.
The following is a partial list
of currently distributed performance standards
and specs along with the organizations who publish
them. Contact these organizations directly to
obtain copies.
- American Society for Testing
and Materials, West Conshohocken, PA
- ASTM C 1060-97 Practice for
Thermographic Inspection of Insulation Installations
in Envelope Cavities of Frame Buildings
- ASTM C-1153-97 Practice for
the Location of Wet Insulation in Roofing Systems
Using Infrared Imaging
- ASTM E 1316-97 Terminology
for Nondestructive Examinations
- ASTM E 1862-97 Standard Test
Methods for Measuring and Compensating for Reflected
Temperature Using Infrared Imaging Radiometers
- ASTM E 1933-97 Standard Test
Methods for Measuring and Compensating for Emissivity
Infrared Imaging Radiometers
- ASTM E 1934-97 Standard Guide
for Examining Electrical and Mechanical Equipment
with Infrared Thermography
- Infraspection Institute, Burlington,
NJ
- Guidelines for Infrared Inspection
of Building Envelopes and Insulated Roofs
- Guideline for Measuring Distance/Target
Size Values for Quantitative Thermal Imaging
Cameras
- Guideline for Measuring and
Compensating for Reflected Temperature, Emittance
and Transmittance
- Guidelines for Infrared Inspection
of Electrical and Mechanical Systems
- International Electrical Testing
Association, Morrison, CO
- Acceptance Testing Specifications
for Electrical Power Distribution Equipment
and Systems
- Maintenance Testing Specifications
for Electrical Power Distribution Equipment
and Systems
- National Fire Protection Association,
Quincy MA
- NFPA 70B Recommended Practice
for Electrical Equipment Maintenance
Proper conduct of an infrared
inspection and interpretation of data require
thorough training and certification by a recognized
training agency. For more information on training
and certification, contact Infraspection Institute
at 609-239-4788 or online at www.infraspection.com
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July
22, 2002
Sponsored
by:
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Proper
Spectral Response
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Choosing
the proper equipment for an infrared inspection
is of paramount importance when performing an
infrared inspection.
Each model of infrared imaging
system has many unique operating characteristics
which must be considered before a project is undertaken.
Of these, perhaps the most important is spectral
response.
Spectral response for an imager
generally falls into two categories: 2-5 microns
(near infrared) or 8-14 microns (far infrared).
Because spectral response can limit one's ability
to perform certain types of inspections, it is
critical that a thermographer understand how spectral
response can affect his/her work.
Below are some generally
recommended spectral responses for different types
of P/PM applications.
| Application |
2-5 microns |
8-14 microns |
Indoor electrical systems
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X
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X
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| Outdoor electrical systems |
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X
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| High temperature targets |
X
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| Highly reflective targets |
X
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| Boiler/heater tubes - gas
fired |
X
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| Long distance imaging |
|
X
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| Smooth surfaced roofs |
X
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| Gravel surfaced roofs |
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