ULTRAPROBETM 100
INSTRUCTION MANUAL
VOLUME 1.3
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The ULTRAPROBE 100 provides easy, accurate leak detection and mechanical inspection through advanced
ultrasonic technology.
Before you begin testing, it is advisable to familiarize yourself with the basic components of your kit.
1. PISTOL HOUSING
The main component of the Ultraprobe is its' pistol housing. From back to front, let's examine each part.
A. Bargraph Display: The display consists of a ten segment LED bargraph that will indicate ultrasonic signal
strength. A low number of LEDs indicate a low level of ultrasound, conversly more intense ultrasonic
signals will displaymore LEDs.
B. Battery Level Light: This red light turns on only when the batteries need to be replaced.
NOTE: When the trigger on/off switch is pulled to the on position the Battery Level Light will flicker on
and then stay off. This is normal and has no relation to battery condition.
C. SensitivitySelectionDial: Thereareeight(8)sensitivitylevelswhichreadoutinrelateddecibelsof"0"to"70".
Asthedialisturnedtotheright, to"0",thesensitivityoftheinstrumentincreases. Asthedialisturnedtotheleft,
to"70",thesensitivtydecreases. Alowlevelultrasoundemissionproduceslowamplitude. Forthisreason,the
instrumentshouldbeinahighsensitivityposition. 0isthehighsensitivityposition. 0isadBindicationof
thresholddetectionfortheinstrument. Forhigheramplitudesignals,movethesensitivitytothelefttowards"70".
ThedialdBindications,alongwiththeLEDindicationsinthebargraphmaybeusedtoestablishdBlevels. To
dothis,justadd3dBforeachLEDbargraphindicationtothedBlevelsetinthesensitivitydial. EX:0dBonthe
sensitivitydial, plus3LEDbargrahlevels=9dB(0+9). 40dBonthesensitivitydialplus4bargraphs=52dB
(40+12)
D. HeadSetJack: Thisiswhereyouplugintheheadset. Besuretoplugitinfirmlyuntilitclicks.
Shouldataperecorderbeutilized,thisiswherethecord forthetaperecorderisinserted.(Usea
miniphoneplug).
E. Trigger Switch: This is located on the underside of the Ultraprobe 100. The Ultraprobe is always "off"
until the trigger switch is pressed. To operate, simply press the trigger; to turn the instrument off, release
thetrigger.
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2.
SCANNING MODULE
This module is utilized to receive air-borne ultrasound such as
theultrasoundsemittedbypressureleaksandelectricaldischarges.
To use, make sure it is plugged in to the front end of the metered
pistol housing by aligning the plug with the receptical and inserting
it firmly.
To use the Scanning Module:
1. Plug in to front end.
2. Start with the sensitivity selection dial at maximum (8).
3. Starttoscanthetestarea.
Scanning Module
a. The method of air borne detection is to go from the "gross to the fine". If there is too much
ultrasound in the area, reduce the sensitivity, place the RUBBER FOCUSING PROBE (described
below) over the scanning module and proceed to follow the test sound to its' loudest point. If it is difficult to
locate the sound due to a high intensity signal, keep reducing the sensitivity and following the meter to the
loudest point.
RUBBER FOCUSING PROBE: The Rubber Focusing Probe is a circular shaped rubber shield. It is used to
block out stray ultrasound and to assist in narrowing the field of reception of the Scanning Module. It also
increases the sensitivity. To use, simply slip it over the front of the scanning module or the contact module.
NOTE: To prevent damage to the module plug, always remove the module BEFORE attaching and removing the
RubberFocusingProbe.
3. CONTACT (STETHOSCOPE) MODULE
This is the module with the metal rod. This rod is utilized as a
"wave-guide" that is sensitive to ultrasound generated internally such as
within a pipe, bearing housing, steam trap or wall. Once stimulated by
ultrasound, it transfers the signal to a piezoelectric transducer located
directly in the module housing.
To use the Stethoscope Module:
1. Align the pin located at the rear of the module with the jack in
the front end of the Metered Pistol Housing and plug in firmly.
2. Touch test area.
3. As with the scanning module, go from the "gross" to the "fine". Start a
maximum sensitivity on the Sensitivity Selection Dial and proceed to
reduce the sensitivity until a satisfactory sound and meter level is
achieved.
Contact Module
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4. HEADSET
This heavy duty headset is designed to block out intense sounds often found in industrial environments so that
the user may easily hear the sounds received by the ULTRAPROBE. To use, simply plug the headset cord into the
headset jack on the metered pistol housing, and place the headphones over your ears. If a hard hat is to be worn, it
is recommended to use UE Systems' model UE-DHC-2HH Hard Hat Headphones which are specifically
designedforhardhatuse.
A. For those situations in which it is not possible or difficult to wear the standard headphones
described above, UE Systems has two options available: 1. the DHC 1991Earpiece which loops
around the ear, and 2. the SA-2000 Speaker Amplifier which is a loud speaker that is compatible
with the Ultraprobe headphone output jack.
5. WTG-1 WARBLE TONE GENERATOR (OPTION)
The WTG-1 Tone Generator is an ultrasonic transmitter designed to flood an area with ultrasound. It is used for a
special type of leak test. When placed inside an empty container or on one side of a test item, it will flood that area
with an intense ultrasound that will not penetrate any solid but will flow through any existing fault or void. By
scanningwiththe ScanningModule, emptycontainerssuchaspipes, tanks, windows, doors, bulkheadsorhatches
can be instantly checked for leakage. This Tone Generator is a WARBLE TONE GENERATOR. This internation-
ally patented transmitter sweeps through a number of ultrasonic frequencies in a fraction of a second to produce a
strong, recognizable"Warble"signal. Thewarbletonepreventsastandingwaveconditionwhichcanproducefalse
readingsandprovidesforaconsistencyoftestinginpracticallyanymaterial.
To use the WARBLE TONE GENERATOR:
1. Turn Tone Generator on by selecting either "LOW" for a low amplitude signal (usually recommended for
small containers) or "HIGH" for high amplitude. In high, the Warble Tone Generator will cover up to
4,000cubicfeet(121.9cu. meters)ofunobstructedspace.
When the Tone Generator is on, a red light (located below the recharge jack in the front) flickers.
2. Place the Warble Tone Generator within the test item/container and seal or close it. Then scan the
suspect areas with the Scanning Module in the Ultraprobe and listen for where the "warble"
ultrasoundpenetrates.
As an example, if the item to be tested is the seal around a window, place the Warble Tone Generator
on one side of the window, close it and proceed to scan on the opposite side.
To test the condition of the Warble Tone Generator battery, set to the LOW INTENSITY position and
listen to the sound through the Ultraprobe headphones. A smooth continuous warbling sound should be heard.
Ifa"beeping"isheardinstead, thenafullrechargeoftheWarbleToneGeneratorisindicated.
To charge the Warble Tone Generator:
1.Usetherecharger.
2. Plugtherechargercordintotherechargejacklocatedon
top of the front panel.
3. Plug the recharger into the local current supply
4. A complete charge will take 7 hours.
5. Since there is no memory problem, the Tone Generator
maybechargedaftershortintervalsofuse.
WTG1 WARBLE TONE
GENERATOR (OPTIONAL)
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ULTRAPROBE APPLICATIONS
1. LEAK DETECTION
This section will cover airborne leak detection of pressure and vacuum systems. (For information concerned
withinternalleakssuchasinValvesandSteamTraps, refertotheappropriatesections).
Whatproducesultrasoundinaleak? Whenagaspassesthrougharestrictedorificeunderpressure, itisgoingfrom
a pressurized laminar flow to low pressure turbulent flow. (Fig. 1). The turbulence generates a broad spectrum of
sound called "white noise". There are ultrasonic components in this white noise. Since the ultrasound will be
loudest by the leak site, the detection of these signals is usually quite simple.
PRESSURELEAK
FIGURE 1
VACUUM LEAK
FIGURE 2
A leak can be in a pressurized system or in a vacuum system. In both instances, the ultrasound will be produced in
themannerdescribedabove. Theonlydifferencebetweenthetwoisthatavacuumleakwillusuallygenerateless
ultrasonic amplitude than a pressure leak of the same flow rate. The reason for this is that the turbulence produced
by a vacuum leak is occuring within the vacuum chamber while the turbulence of a pressure leak is generated in the
atmosphere.(Fig.2).
What type of gas leak will be detected ultrasonically? Generally any gas, including air, will produce a turbulence
whenitescapesthrougharestrictedorifice. Unlikegasspecificsensors, theUltraprobeissound specific. Agas
specificsensorislimitedtotheparticulargasitwasdesignedtosense(e.g., helium). TheUltraprobecansenseany
typeofgasleaksinceitdetectstheultrasoundproducedbytheturbulenceofaleak.
Because of its versatility, the Ultraprobe may be utilized in a wide variety of leak detection. Pneumatic systems
maybechecked,pressurizedcables,suchasthoseutilizedbytelephonecompanies,maybetested. Airbrake
systemsonrailroadcars,trucks,andbusesmaybechecked. Tanks,pipes,housings,casingsandtubesareeasily
testedforleakagebypressurizingthem.Vacuumsystems,turbineexhausts,vacuumchambers,materialhandling
systems,condensers,oxygensystemscanalleasilybetestedforleakagebylisteningfortheturbulenceoftheleak.
A. HOW TO LOCATE LEAKS
1. Use the SCANNING MODULE.
2. Start off with the sensitivity selection at 0 (Maximum).
3. Begin to scan by pointing the module towards the test area. The procedure is to go from the "gross" to
the "fine" - more and more subtle adjustments will be made as the leak is approached.
4. If there is too much ultrasound in the area, reduce the sensitivity setting and continue to scan.
5. If it is difficult to isolate the leak due to competing ultrasound, place the RUBBER FOCUSING PROBE
over the scanning module and proceed to scan the test area.
6. Listen for a "rushing" sound while observing the meter.
7. Follow the sound to the loudest point. The meter will show a higher reading as the leak is approached.
8. In order to focus in on the leak, keep reducing the sensitivity setting and move the instrument closer to
the suspected leak site until you are able to confirm a leak.
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B. TO CONFIRM A LEAK:
Position the Scanning Module, or the rubber focusing probe (if it is on the scanning module) close to the
suspect leak site and move it, slightly, back and forth, in all directions. If the leak is at this location, the sound will
increase and decrease in intensity as you sweep over it. In some instances, it is useful to position the rubber focusing
probe directly over the suspect leak site and push down to "seal" it from surrounding sounds. If it is the leak, the
rushing sound will continue. If it is not the leak site, the sound will drop off.
C. OVERCOMING DIFFICULTIES
1. Competing Ultrasounds
If competing ultrasounds make it difficult to isolate a leak, there are two approaches to be taken:
a. Manipulate the environment. This procedure is fairly straight forward. When possible, turn off
the equipment that is producing the competing ultrasound or isolate the area by closing a
door or window.
b. Manipulate the instrument and use shielding techniques. If environmental manipulation is not
possible, trytogetasclosetothetestsiteaspossible, andmanipulatetheinstrumentsothat
it is pointing away from the competing ultrasound. Isolate the leak area by reducing the sensitivity of the
unit and by pushing the tip of the rubber focusing probe up to the test area, checking a small section at a
time.
1. SHIELDING TECHNIQUES
Sinceultrasoundisahighfrequency, shortwavesignal, itcanusuallybeblockedor"shielded". NOTE: When
using any method, be sure to follow your plant's or company's safety guidelines. Some common techniques are:
a. Body: placeyourbodybetweenthetestareaandthecompetingsoundstoactasabarrier
b. Clip Board: Position the clip board close to the leak area and angle it so that it acts as a
barrier betweenthetestareaandthecompetingsounds
c. Gloved Hand: (USE CAUTION) using a gloved hand, wrap the hand around the rubber
focusingprobe tip so that the index finger and the thumb are close to the very end and place the rest of the
hand on the test site so that there is a complete barrier of the hand between the test area and the background
noise. Move the hand and instrument together over the various test zones.
d. Wipe rag: This is the same method as the "gloved hand" method, only, in addition to the
glove, use a wipe rag to wrap around the rubber focusing probe tip. Hold the rag in the gloved hand so that it
actsasa"curtain",i.e., there is enough material to cover the test site without blocking the open end of the
rubber focusing probe. This is ususally the most effective method since it uses three barriers: the rubber
focusingprobe, theglovedhandandtherag.
e. Barrier: When covering a large area, it is sometimes helpful to use some reflective material,suchasa
welders curtain or a drop cloth, to act as a barrier. Place the material so that it acts as a "wall" between the test
areaandthecompetingsounds. Sometimesthe barrier is draped from ceiling to floor, at other times, it is
hungoverrailings.
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D. LOW LEVEL LEAKS
In ultrasonic inspection of leakage, the amplitude of the sound often depends upon the amount of turbulence
generated at the leak site. The greater the turbulence, the louder the signal, the less the turbulence, the lower the
intensity of the signal. When a leak rate is so low that it produces little, if any turbulence that is "detectable", it is
considered "below threshold". If a leak appears to be of this nature:
1. Buildupthepressure(ifpossible)tocreategreaterturbulence.
2. Utilize LIQUID LEAK AMPLIFIER.
This patented method incorporates a UE Systems product called LIQUID LEAK AMPLIFIER, or LLA for
short. LLA is a uniquely formulated liquid substance that has special chemical properties. Used as an ultra-
sonic "bubble test, a small amount of LLA is poured over a suspected leak site. It produces a thin film through
which the escaping gas will pass. When it comes in contact with a low flow of gas, it quickly forms a
large number of small "soda-like" bubbles that burst as soon as they form. This bursting effect produces
anultrasonicshockwavethatisheardasacracklingsoundintheheadphones. Inmanyinstancesthe
bubbles will not be seen, but they will be heard. This method is capable of obtaining successful leak
checksinsystemswithleaksaslowas1x10-6 ml/sec.
NOTE: The low surface tension of the LLA is the reason small bubbles form. This can be negatively changed
by contamination of the leak site with another leak fluid which can block LLA or cause large bubbles to form.
If contaminated, clean the leak site with water, solvent or alcohol (check with plant regulations before
selectingadecontaminatingcleaningagent).
E. TONE TEST (Ultratone )
The Tone Test is an ultrasonic method for non-destructive testing which is used when it is difficult to pressurize
or draw a vacuum in a system. This ultrasonic test is applicable to a wide range of items, including:
CONTAINERS, TUBES, PIPES, HEAT EXCHANGERS, WELDS , GASKETS, SEALS, DOORS, WINDOWS,
OR HATCHES.
The test is conducted by placing an ultrasonic transmitter, called TONE GENERATOR, inside (or on one side) of
the test item. The warble pulse-signal from the TONE GENERATOR will instantly "flood" the test item and
penetrateanyexistingleakhole. Dependingonconfigurationandmaterial, eventhinspotsincertainmetalscanbe
vibrated by the signal. By scanning for sonic penetration on the exterior surface (or opposite side) of the test item
with the Ultraprobe, the leak will be detected. It will be heard as a high pitched warble, similar to bird chirping.
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The Tone Test incorporates two basic components: a TONE GENERATOR (an ultrasonic transmitter) , and the
Scanning Module in the Ultraprobe. To conduct the test:
1. Make certain the test item has no fluids or contaminants such as water, mud, sludge, etc., that can block the path
of the transmitted ultrasound.
2. Place the Tone Generator within the container, (if it is a room, door or window to be tested, place the Tone
Generator on one side pointing in the direction of the area to be tested) and close, or seal so that the Tone Genera-
tor is enclosed within.
NOTE: The size of the test area will determine the amplitude selection of the Tone Generator. If the item to be
tested is small, select the LOW position. For larger items, use the HIGH position.
3. Scan the test area with the Ultraprobe as outlined in LEAK DETECTION procedure. (i.e., start with the
sensitivityselectionat8andproceeddown).
When positioning the Tone Generator, place the transducer facing and close to the most crucial test area. If a
generalareaistobechecked, positiontheToneGeneratorsothatitwillcoveraswideanareaaspossiblebyplacing
it in the "middle" of the test item.
How far will the sound travel? The Tone Generator is designed to cover approximately 4000 cubic feet (1219 cu
meters) of uninterrupted space. This is slightly larger than the size of a tractor trailer. Placement is dependent
upon such variables as the size of the leak to be tested, the thickness of the test wall and the type of material tested
(i.e. is it sound absorbant or sound reflective?). Remember, you are dealing with a high frequency, short wave
signal. If the sound is expected to travel through a thick wall, place the Tone Generator close to the test zone, if it
is a thin metallic wall, move it farther back and use "low". For uneven surfaces it may be necessary to use two
people. One person will move the Tone Generator slowly close to and around the test areas while another person
scans with the Ultraprobe on the other side.
Do not use the Tone test in a complete vacuum.
Ultrasound will not travel in a vacuum. Sound waves need molecules to vibrate and conduct the signal. There are
nomoveablemoleculesinacompletevacuum.
If a partial vacuum is to be drawn where there are still some air molecules to vibrate, then the Tone Test may be
implementedsuccessfully.
In a laboratory, a form of the Tone Test is utilized in seal leaks of an electron beam microscope. The test chamber
hasbeenfittedwithaspeciallydesignedtransducertoemitthedesiredtoneandapartialvacuumiscreated. Auser
thenscansallseamsforsonicpenetration. TheToneTesthasalsobeeneffectivelyutilizedtotesttanksbeforethey
are put on line, piping, refrigerator gaskets, caulking around doors and windows for air infiltration testing, heat
exchangers for leaking tubes, as a Q.C. test for automobile wind noise and water leaks, on aircraft to test for
problemsassociatedwithcabinpressureleaksandgloveboxesforsealintegritydefects.
Optional
PipeThreaded
ToneGenerator
UE-WTG2SP
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2. ELECTRIC ARC, CORONA, TRACKING DETECTION
There are three basic electrical problems that are detected with the Ultraprobe 500:
Arcing: Anarcoccurswhenelectricityflowsthroughspace. Lightningisagoodexample.
Corona: Whenvoltageonanelectricalconductor,suchasanantennaorhighvoltage
transmission line exceeds the threshold value, the air around it begins to ionize to form a
blue or purple glow.
Tracking:Oftenreferedtoas"babyarcing", followsthepathofdamagedinsulation.
Although theoretically the Ultraprobe 100 can be used in low, medium and high voltage systems, most of the
applicationstendtobeinmediumandhighvoltagesystems.
When electricity escapes in high voltage lines or when it "jumps" across a gap in an electrical connection, it disturbs
the air molecules around it and generates ultrasound. Most often this sound will be perceived as a crackling or
"frying" sound, in other situations it will be heard as a buzzing sound.
Typicalapplicationsinclude: insulators, cable, switchgear, bussbars, relays, contactors, junctionboxes. Insubsta-
tions,componentssuchasinsulators,transformersandbushingsmaybetested.
Ultrasonictestingisoftenusedatvoltagesexceeding2,000volts, especiallyinenclosedswitchgear. Sinceultra-
soundemissionscanbedetectedbyscanningarounddoorseamsandairvents, itispossibletodetectseriousfaults
such as arcing, tracking and corona without taking the switchgear off line to perform an infrared scan. However, it
isrecommendedthatbothtestsbeusedwithenclosedswitchgear.
NOTE: When testing electrical equipment, follow all your plant or company safety procedures. When
indoubt,askyoursupervisor. Nevertouch liveelectricalapparatuswiththeUltraprobe.
The method for detecting electric arc and corona leakage is similar to the procedure outlined in leak detection.
Instead of listening for a rushing sound, a user will listen for a crackling or buzzing sound. In some instances, as in
tryingtolocatethesourceofradio/TVinterferenceorinsubstations, thegeneralareaofdisturbancemaybelocated
withagrossdetectorsuchasatransistorradioorawide-bandinterferencelocator. Oncethegeneralareahasbeen
located, the scanning module of the Ultraprobe is utilized with a general scan of the area. The sensitivity is re-
duced if the signal is too strong to follow. When this occurs, reduce the sensitivity to get a mid-line reading on the
meter and continue following the sound until the loudest point is located.
Determining whether a problem exists or not is relatively simple. By comparing sound quality and sound levels
among similar equipment, the problem sound will tend to be quite different.
On lower voltage systems, a quick scan of bus bars often will pick up a loose connection. Checking junction boxes
canrevealarcing. Aswithleakdetection, thecloseronegetstotheemissionsite, thelouderthesignal.
Test switchgear,transformers,etc.
for arcing, tracking & corona.
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3. DETECTING BEARING WEAR
Ultrasonic inspection and monitoring of bearings is by far the most reliable method for detecting incipient bearing
failure. The ultrasonic warning appears prior to a rise in temperature or an increase in low frequency vibration
levels. Ultrasonic inspection of bearings is useful in recognizing:
a. The beginning of fatigue failure.
b. Brinelling of bearing surfaces.
c. Flooding of or lack of lubricant.
In ball bearings, as the metal in the raceway, roller or ball bearing begins to fatigue, a subtle deformation begins to
occur. This deforming of the metal will produce an increase in the emission of ultrasonic sound waves.
Changes in amplitude of from 12 to 50 times the original reading is indication of incipient bearing failure. When a
readingexceedsanypreviousreadingby12db, itcanbeassumedthatthebearinghasenteredthebeginningofthe
failuremode.
This information was originally discovered through experimentation performed by NASA on ball bearings. In tests
performed while monitoring bearings at frequencies ranging from 24 through 50 kHz, they found that the changes
in amplitude indicate incipient (the onset of) bearing failure before any other indicators including heat and vibra-
tionchanges. Anultrasonicsystembasedondetectionandanalysisofmodulationsofbearingresonancefrequen-
ciescanprovidesubtledetectioncapability;whereasconventionalmethodsareincapableofdetectingveryslight
faults. As a ball passes over a pit or fault in the race surface, it produces an impact. A structural resonance of one of
the bearing components vibrates or "rings" by this repetitive impact. The sound produced is observed as an in-
crease in amplitude in the monitored ultrasonic frequencies of the bearing.
Brinelling of bearing surfaces will produce a similar increase in amplitude due to the flattening process as the balls
get out of round. These flat spots also produce a repetitive ringing that is detected as an increase in amplitude of
monitoredfrequencies.
TheultrasonicfrequenciesdetectedbytheUltraprobearereproducedasaudiblesounds. This"heterodyned"
signalcangreatlyassistauserindeterminingbearingproblems. Whenlistening, itisrecommendedthatauser
become familiar with the sounds of a good bearing. A good bearing is heard as a rushing or hissing noise. Crack-
lingorroughsoundsindicateabearinginthefailurestage. Incertaincasesadamagedballcanbeheardasa
clickingsoundwhereasahighintensity, uniformroughsoundmayindicateadamagedraceoruniformballdamage.
Loud rushing sounds similar to the rushing sound of a good bearing only slightly rougher, can indicate lack of
lubrication. Short duration increases in the sound level with "rough" or "scratchy" components indicate a rolling
element hitting a "flat" spot and sliding on the bearing surfaces rather than rotating. If this condition is detected,
morefrequentexaminationsshouldbescheduled.
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DETECTING BEARING FAILURE
COMPARATIVE TESTING. The comparative method involves testing two or more similar bearings and "com-
paring"potentialdifferences.
FOR COMPARATIVE TEST
1. Usecontact(stethoscope)module.
2. Select a "test spot" on the bearing housing. Touch that spot with the contact module. In ultrasonic sensing,
the more mediums or materials ultrasound has to travel through, the less accurate the reading will be.
Therefore, be sure the contact probe is actually touching the bearing housing. If this is difficult, touch a
greasefittingortouchasclosetothebearingaspossible.
3. Approachthebearingsatthesameangle,touchingthesameareaonthebearinghousing.
4. Reduce sensitivity (if unsure of this procedure, refer to SENSITIVITY SELECTION DIAL)
5. Listen to bearing sound through headphones to hear the "quality" of the signal for proper interpretation.
6. Selectsametypebearings undersimilarloadconditionsandsamerotationalspeed.
7. Comparedifferencesofmeterreadingandsoundquality.
It is important to consider two elements of potential failure. One is lack of lubrication while the other is over
lubrication.
Normalbearingloadscausesanelasticdeformationoftheelementsinthecontactareawhichgiveasmooth
ellipticalstressdistribution. Butbearingsurfacesarenotperfectlysmooth. Forthisreason, theactualstress
distribution in the contact area will be affected by a random surface roughness. In the presence of a lubricant film
on abearingsurface, thereisadampeningeffectonthestressdistributionandtheacousticenergyproducedwillbe
low. Should lubrication be reduced to a point where the stress distribution is no longer present, the normal rough
spotswillmakecontactwiththeracesurfacesandincreasetheacousticenergy. Thesenormalmicroscopic
disuniformities will begin to produce wear and the possibilities of small fissures may develop which contributes to
the "Pre-Failure" condition. Therefore, aside from normal wear, the fatigue or service life of a bearing is strongly
influenced by the relative film thickness provided by an appropriate lubricant.
SLOW SPEED BEARINGS
Monitoring slow speed bearings is possible with the Ultraprobe 100. Due to the sensitivity range, it is quite
possible to listen to the acoustic quality of bearings. In extremely slow bearings (less than 25 RPM), it is often
necessarytodisregardthemeterandlistentothesoundofthebearing. Intheseextremesituations, thebearings
are usually large (1"-2" and up) and greased with high viscosity lubricant. Most often no sound will be heard as the
greasewillabsorbmostoftheacousticenergy. Ifasoundisheard, usuallyacracklingsound, thereissomeindica-
tion of deformity occurring.
4. GENERAL MECHANICAL TROUBLE SHOOTING
As operating equipment begins to fail due to component wear, breakage or misalignment , sonic and more
importantly, ultrasonicshiftsoccur. Theaccompanyingsoundpatternchangescansavetimeandguessworkin
diagnosingproblemsiftheyareadequatelymonitored. Therefore, anultrasonichistoryofkeycomponentscan
prevent unplanned down-time. And just as important, if equipment should begin to fail in the field, the
ULTRAPROBE can be extremely useful in trouble shooting problems.
TROUBLE SHOOTING:
1. Usethecontact(stethoscope)module.
2. Touchtestarea(s):listenthroughheadphonesandobservethemeter.
3. Adjust sensitivity until mechanical operation of the equipment is heard clearly.
4. Probeequipmentbytouchingvarioussuspectareas.
5. To focus in on problem sounds, while probing, reduce sensitivity gradually to assist in locating the prob-
lem sound at its' loudest point. (This procedure is similar to the method outlined in LEAK LOCATION, i.e.,
follow the sound to its loudest point.)
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5. LOCATING FAULTY STEAM TRAPS
An ultrasonic test of steam traps is a positive test. The main advantage to ultrasonic testing is that it isolates the
areabeingtestedbyeliminatingconfusingbackgroundnoises. Ausercanquicklyadjusttorecognizingdifferences
amongvarioussteamtraps, ofwhichtherearethreebasictypes: mechanical, thermostaticandthermodynamic.
Whentestingsteamtrapsultrasonically:
1. Determine what type of trap is on the line. Be familiar with the operation of the trap. Is it intermittent or
continousdrain?
2. Try to check whether the trap is in operation (is it hot or cold? Put your hand near, but do not touch the trap,
or, better yet, use a non-contact infrared thermometer).
3. Usethecontact(stethoscope)module.
4. Try to touch the contact probe towards the discharge side of the trap. Press the trigger and listen.
5. Listen for the intermittent or continuous flow operation of the trap. Intermittent traps are usually the inverted
bucket, thermodynamic (disc) and thermostatic (under light loads). Continuous flow: include the float, float
and thermostatic and (usually) thermostatic traps. While testing intermittent traps, listen long enough to gauge
the true cycle. In some cases, this may be longer than 30 seconds. Bear in mind that the greater the load that
comes to it, the longer period of time it will stay open.
In checking a trap ultrasonically, a continuous rushing sound will often be the key indicator of live steam passing
through. There are subtleties for each type of trap that can be noted.
Use the sensitivity levels of the Sensitivity Selection Dial to assist your test. If a low pressure system is to be
checked, adjust thesensitivity UPtoward8;ifahighpressuresystem(above100psi)istobechecked, reduce the
sensitivitylevel. (Someexperimentationmaybenecessarytoarriveatthemostdesirableleveltobetested.) Check
upstream and reduce the sensitivity so that the meter reads about 50% or lower, then touch the trap body down-
streamandcomparereadings.
GENERAL STEAM/CONDENSATE/FLASH STEAM CONFIRMATION
In instances where it may be difficult to determine the sound of steam, flash steam or condensate,
1. touch at the immediate downstream side of the trap and reduce the sensitivity to get a mid-line
reading on the meter (about 50%).
2. move6-12inches(15.2-30.5cm)downstream andlisten. Flashingsteamwillshowalargedrop
off in intensity while leaking steam will show little drop off in intensity.
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INVERTED BUCKET TRAPS normally fail in the open position because the trap loses its prime. This condition
means a complete blow-through, not a partial loss. The trap will no longer operate intermittently. Aside from a
continuous rushing sound, another clue for steam blow-through is the sound of the bucket clanging against the side
of the trap.
A FLOAT AND THERMOSTATIC trap normally fails in the "closed" position. A pinhole leak produced in the
ball float will cause the float to be weighted down or water hammer will collapse the ball float. Since the trap is
totally closed - no sound will be heard. In addition, check the thermostatic element in the float and thermostatic
trap. If the trap is operating correctly, this element is usually quiet; if a rushing sound is heard, this will indicate
either steam or gas is blowing through the air vent. This indicates that the vent has failed in the open position and
iswastingenergy.
THERMODYNAMIC (DISC) traps work on the difference in dynamic reponse to velocity change in the flow of
compressibleandincompressiblefluids. Assteamenters,staticpressureabovethediscforcesthediscagainstthe
valveseat. Thestaticpressureoveralargeareaovercomesthehighinletpressureofthesteam. Asthesteamstarts
tocondense, thepressureagainstthedisclessensandthetrapcycles. Agooddisctrapshouldcycle(hold-dis-
charge-hold) 4-10 times per minute. When it fails, it usually fails in the open position, allowing continuous blow-
throughofsteam.
THERMOSTATIC TRAPS (bellows & bimetallic) operate on a difference in temperature between condensate and
steam. They build up condensate so that the temperature of condensate drops down to a certain level below
saturation temperature in order for the trap to open. By backing up condensate, the trap will tend to modulate
openorcloseddependingonload.
In a bellows trap, should the bellows become compressed by water hammer, it will not function properly. The
occurrenceofaleakwillpreventthebalancedpressureactionofthesetraps. Wheneitherconditionoccurs, thetrap
will fail in its natural position either opened or closed. If the trap fails closed, condensate will back up and no
sound will be heard. If the trap fails open, a continous rushing of live steam will be heard.
With bimetallic traps, as the bimetallic plates set due to the heat they sense and the cooling effect on the plates, they
may not set properly which will prevent the plates from closing completely and allow steam to pass through. This
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