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1297 views
09:30 Feb-24-2006
ugdas
high temp thickness gauge

Dear All ,

We want to do refinery equipment inspection having temp range 350 to 400 deg centigrade. We aould like to share your experince in terms of
1) machines make type 2) probe type3)couplant4) safety condition and other factor

thanks for the support


 
09:37 Mar-02-2006
Scott
Re: high temp thickness gauge Typically in refinery inspection there are plugs (holes) drilled into the insulation with caps that can be removed to access area where reading is to be taken (if part of erosion program). It is difficult to clean the pipe through these small holes. The surafces of pipe is uaually rusted and external pitting. At the temp you suggest the couplant with melt and run off fairly quickly. You can only have the probe (high temp probe) touching the pipe for somewhere between 2-5 sec I believe. Then it must cool for about a minute before taking another reading. It is hard to get good contact with an acceptable backwall signal from the pipe in such a short time frame. They companys also make probe extensions but I dont like these very well. It does give you good access but you lose the dexterity and feeling you have by holding the probe with your fingers. It is possible but results can sometimes be questionable. You have to also be careful to compensate for the temperature variation of the cal block and hot pipe (unless you have a d-meter that does it for you, or you heat your cal block to the same temp as the piping).

----------- Start Original Message -----------
: Dear All ,
: We want to do refinery equipment inspection having temp range 350 to 400 deg centigrade. We aould like to share your experince in terms of
: 1) machines make type 2) probe type3)couplant4) safety condition and other factor
: thanks for the support
------------ End Original Message ------------




 
06:20 Mar-04-2006

Floyd Atkinson

NDT Inspector
American Inspection Society, Inc.,
USA,
Joined Jun 2004
10
Re: high temp thickness gauge
----------- Start Original Message -----------
: Typically in refinery inspection there are plugs (holes) drilled into the insulation with caps that can be removed to access area where reading is to be taken (if part of erosion program). It is difficult to clean the pipe through these small holes. The surafces of pipe is uaually rusted and external pitting. At the temp you suggest the couplant with melt and run off fairly quickly. You can only have the probe (high temp probe) touching the pipe for somewhere between 2-5 sec I believe. Then it must cool for about a minute before taking another reading. It is hard to get good contact with an acceptable backwall signal from the pipe in such a short time frame. They companys also make probe extensions but I dont like these very well. It does give you good access but you lose the dexterity and feeling you have by holding the probe with your fingers. It is possible but results can sometimes be questionable. You have to also be careful to compensatefor the temperature variation of the cal block and hot pipe (unless you have a d-meter that does it for you, or you heat your cal block to the same temp as the piping).
: : Dear All ,
: : We want to do refinery equipment inspection having temp range 350 to 400 deg centigrade. We aould like to share your experince in terms of
: : 1) machines make type 2) probe type3)couplant4) safety condition and other factor
: : thanks for the support
------------ End Original Message ------------
______________________________________________________


_________________BEGIN Response_______________________

I have experience using the Krautkramer "t" mike and the 1/2" diameter probe using GE brand high temp couplant grease 350-500 degrees farenheit temp rating. The results were fairly accurate utlizing the thickness wedge available at pre-calibration.The temperature variance is often difficult because you actually have to have a temp probe also with to detemine this information. I also have over come the surface rough ness problem by having the standard eqipment of a chisel point carbon steel file with handle to remove rust.Use every precaution when using this as it is often easy to loose in the pipe rack maze. Use a rugged leather lanyard from your favorite boot supply outlet. This must never be used on stainless steel piping because of the damages which may occur to the customer's piping. Stainless steel to stainless steel scraping only. Remember that a hand magnet make be a useful tool to detemine if you are dealing with carbon steel piping or stainless steel piping. Keep the hand compass in a separate location as you don't want to mix the magnets up and demag one or the other.
The use of an extended compass will help in determining the directions of your piping directions because of the maze during orientation for your mapping information and tracing information. Calibrate with the same grease as used in the field at the dispatch trailer. Beacause of the standards availability you may not be allowed to take the standad with you. Get a very accurate calibration. atteries strength may affect meter readings. If you are in doubt verify batteries are full strength before inspection operations.

________________END RESPONSE__________________________


 
06:27 Mar-04-2006
Floyd Atkinson
Re: high temp thickness gauge/Spell check corrected ----------- Start Original Message -----------
:
: : Typically in refinery inspection there are plugs (holes) drilled into the insulation with caps that can be removed to access area where reading is to be taken (if part of erosion program). It is difficult to clean the pipe through these small holes. The surafces of pipe is uaually rusted and external pitting. At the temp you suggest the couplant with melt and run off fairly quickly. You can only have the probe (high temp probe) touching the pipe for somewhere between 2-5 sec I believe. Then it must cool for about a minute before taking another reading. It is hard to get good contact with an acceptable backwall signal from the pipe in such a short time frame. They companys also make probe extensions but I dont like these very well. It does give you good access but you lose the dexterity and feeling you have by holding the probe with your fingers. It is possible but results can sometimes be questionable. You have to also be careful to compensate for the temperature variation of the cal block and hot pipe (unless you have a d-meter that does it for you, or you heat your cal block to the same temp as the piping).
: : : Dear All ,
: : : We want to do refinery equipment inspection having temp range 350 to 400 deg centigrade. We aould like to share your experince in terms of
: : : 1) machines make type 2) probe type3)couplant4) safety condition and other factor
: : : thanks for the support
: ______________________________________________________
:
: _________________BEGIN Response_______________________
: I have experience using the Krautkramer "t" mike and the 1/2" diameter probe using GE brand high temp couplant grease 350-500 degrees farenheit temp rating. The results were fairly accurate utlizing the thickness wedge available at pre-calibration.The temperature variance is often difficult because you actually have to have a temp probe also with to detemine this information. I also have over come the surface rough ness problem by having the standard eqipment of a chisel point carbon steel file with handle to remove rust.Use every precaution when using this as it is often easy to loose in the pipe rack maze. Use a rugged leather lanyard from your favorite boot supply outlet. This must never be used on stainless steel piping because of the damages which may occur to the customer's piping. Stainless steel to stainless steel scraping only. Remember that a hand magnet make be a useful tool to detemine if you are dealing with carbon steel piping or stainless steel piping. Keep the hand compass in a separate location as you don't want to mix the magnets up and demag one or the other.
The use of an extended compass will help in determining the directions of your piping directions because of the maze during orientation for your mapping information and tracing information. Calibrate with the same grease as used in the field at the dispatch trailer. Because of the standards availability you may not be allowed to take the standard with you. Get a very accurate calibration. Batteries strength may affect meter readings. If you are in doubt verify batteries are full strength before inspection operations. Thanks.
: ________________END RESPONSE__________________________
------------ End Original Message ------------




 
04:45 Mar-05-2006

David Hermanutz

Consultant,
Hbndt.com,
China,
Joined Jul 2012
85
Re: high temp thickness gauge/Spell check corrected Hi,

I have previously used a portable drill with a wire brush attachment to preclean dirty holes. Also try and wipe up the grease after as it can get cooked into place and interfere with the next measurement.

The 37dl from Panametrics has a good hightemp option that corrects for velocity issues on High temperature piping, take an Infrared temp gun or some temp sticks to see what the temperature really is.

Echo to Echo measurements are also a must due to thermal expansion of the delay line in the calibration block. This affects the sound both by physical expansion and velocity shift in the delay material.

I also made a water-cooled jacket probe for continous B-Scan work that allowed for full contact. Make sure that the material you're on isn't affected by the loose water or chlorides.

Regards,

David Hermanutz
Senior Technician
www.westerninspection.com

----------- Start Original Message -----------
: :
: : : Typically in refinery inspection there are plugs (holes) drilledinto the insulation with caps that can be removed to access area where reading is to be taken (if part of erosion program). It is difficult to clean the pipe through these small holes. The surafces of pipe is uaually rusted and external pitting. At the temp you suggest the couplant with melt and run off fairly quickly. You can only have the probe (high temp probe) touching the pipe for somewhere between 2-5 sec I believe. Then it must cool for about a minute before taking another reading. It is hard to get good contact with an acceptable backwall signal from the pipe in such a short time frame. They companys also make probe extensions but I dont like these very well. It does give you good access but you lose the dexterity and feeling you have by holding the probe with your fingers. It is possible but results can sometimes be questionable. You have to also be careful to compensate for the temperature variation of the cal block and hot pipe (unless you have a d-meter that does it for you, or you heatyour cal block to the same temp as the piping).
: : : : Dear All ,
: : : : We want to do refinery equipment inspection having temp range 350 to 400 deg centigrade. We aould like to share your experince in terms of
: : : : 1) machines make type 2) probe type3)couplant4) safety condition and other factor
: : : : thanks for the support
: : ______________________________________________________
: :
: : _________________BEGIN Response_______________________
: : I have experience using the Krautkramer "t" mike and the 1/2" diameter probe using GE brand high temp couplant grease 350-500 degrees farenheit temp rating. The results were fairly accurate utlizing the thickness wedge available at pre-calibration.The temperature variance is often difficult because you actually have to have a temp probe also with to detemine this information. I also have over come the surface rough ness problem by having the standard eqipment of a chisel point carbon steel file with handle to remove rust.Use everyprecaution when using this as it is often easy to loose in the pipe rack maze. Use a rugged leather lanyard from your favorite boot supply outlet. This must never be used on stainless steel piping because of the damages which may occur to the customer's piping. Stainless steel to stainless steel scraping only. Remember that a hand magnet make be a useful tool to detemine if you are dealing with carbon steel piping or stainless steel piping. Keep the hand compass in a separate location as you don't want to mix the magnets up and demag one or the other.
: The use of an extended compass will help in determining the directions of your piping directions because of the maze during orientation for your mapping information and tracing information. Calibrate with the same grease as used in the field at the dispatch trailer. Because of the standards availability you may not be allowed to take the standard with you. Get a very accurate calibration. Batteries strength may affect meter readings. If you are in doubtverify batteries are full strength before inspection operations. Thanks.
: : ________________END RESPONSE__________________________
------------ End Original Message ------------




 
06:02 Mar-07-2006

Zahir

Engineering
Universiti Kebangsaan Malaysia,,
Malaysia,
Joined Jan 2001
5
Re: high temp thickness gauge/Spell check corrected Hi,
There's another method of detecting General Wall Loss under insulation / high temp up to 500 degree.
Probably you may try apply Pulsed Eddy Current.
But you must be aware of its limitation & capability.
I've done this survey myself but the accuracy is about 5%. You can check RTD website or ShellGlobalSolution Website for more info.
The best part about the technique is you can used it without removal off insulation (thinkness insulation less than 250mm).

Good Luck
Rgds
Zahir

P/s :- How can i find a company that can fabricate the water cooling probe? Anyone?


----------- Start Original Message -----------
: Hi,
: I have previously used a portable drill with a wire brush attachment to preclean dirty holes. Also try and wipe up the grease after as it can get cooked into place and interfere with the next measurement.
: The 37dl from Panametrics has a good hightemp option that corrects for velocity issues on High temperature piping, take an Infrared temp gun or some temp sticks to see what the temperature really is.
: Echo to Echo measurements are also a must due to thermal expansion of the delay line in the calibration block. This affects the sound both by physical expansion and velocity shift in the delay material.
: I also made a water-cooled jacket probe for continous B-Scan work that allowed for full contact. Make sure that the material you're on isn't affected by the loose water or chlorides.
: Regards,
: David Hermanutz
: Senior Technician
: www.westerninspection.com
: : :
: : : : Typically in refinery inspection there are plugs (holes) drilled into the insulation with caps that can be removed to access area where reading is to be taken (if part of erosion program). It is difficult to clean the pipe through these small holes. The surafces of pipe is uaually rusted and external pitting. At the temp you suggest the couplant with melt and run off fairly quickly. You can only have the probe (high temp probe) touching the pipe for somewhere between 2-5 sec I believe. Then it must cool for about a minute before taking another reading. It is hard to get good contact with an acceptable backwall signal from the pipe in such a short time frame. They companys also make probe extensions but I dont like these very well. It does give you good access but you lose the dexterity and feeling you have by holding the probe with your fingers. It is possible but results can sometimes be questionable. You have to also be careful to compensate for the temperature variation of the cal block and hot pipe (unless you have a d-meter that does it for you, or you heat your cal block to the same temp as the piping).
: : : : : Dear All ,
: : : : : We want to do refinery equipment inspection having temp range 350 to 400 deg centigrade. We aould like to share your experince in terms of
: : : : : 1) machines make type 2) probe type3)couplant4) safety condition and other factor
: : : : : thanks for the support
: : : ______________________________________________________
: : :
: : : _________________BEGIN Response_______________________
: : : I have experience using the Krautkramer "t" mike and the 1/2" diameter probe using GE brand high temp couplant grease 350-500 degrees farenheit temp rating. The results were fairly accurate utlizing the thickness wedge available at pre-calibration.The temperature variance is often difficult because you actually have to have a temp probe also with to detemine this information. I also have over come the surface rough ness problem by having the standard eqipment of a chisel point carbon steel file with handle to remove rust.Use every precaution when using this as it is often easy to loose in the pipe rack maze. Use a rugged leather lanyard from your favorite boot supply outlet. This must never be used on stainless steel piping because of the damages which may occur to the customer's piping. Stainless steel to stainless steel scraping only. Remember that a hand magnet make be a useful tool to detemine if you are dealing with carbon steel piping or stainless steel piping. Keep the hand compass in a separate location as you don't want to mix the magnets up and demag one or the other.
: : The use of an extended compass will help in determining the directions of your piping directions because of the maze during orientation for your mapping information and tracing information. Calibrate with the same grease as used in the field at the dispatch trailer. Because of the standards availability you may not be allowed to take the standard with you. Get a very accurate calibration. Batteries strength may affect meter readings. If you are in doubt verify batteries are full strength before inspection operations. Thanks.
: : : ________________END RESPONSE__________________________
------------ End Original Message ------------




 
01:14 Jan-18-2007
Jamar
Bryant 5e6a9d3147aa


 


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