where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -

1206 views
Technical Discussions
Poena van Staden
Poena van Staden
00:04 Jul-16-2008
Online UTWT acceptable tolerences

We have a project on the go @ Engen Refinery, Durban, South Africa for online piping inspections in accordance with API570. Recently, we incorporated an audit system to verify the acurateness of the UTWT results. The idea behind the audit is not to target the qaulified NDE technicians, but rather to find better ways of repeating TML's (thickness monitoring locations) and surface preparation. Now the big question: What would be a acceptable tolerence on a repeat reading the day later? We all know that it is very difficult (if not impossible) to repeat the exact reading on old piping. Are there a paper available for guidance?
Regards
Poena (HPIA Site Manager)



    
 
 
Navita
Navita
08:09 Jul-17-2008
Re: Online UTWT acceptable tolerences
Probably Mr. Dinesh Gupta, an ASNT Level-III in 7 methods could help you out. Mr. Gupta is based in India, but travels globally for such problems. You can contact him on guptadinesh1966@yahoo.com

----------- Start Original Message -----------
: We have a project on the go @ Engen Refinery, Durban, South Africa for online piping inspections in accordance with API570. Recently, we incorporated an audit system to verify the acurateness of the UTWT results. The idea behind the audit is not to target the qaulified NDE technicians, but rather to find better ways of repeating TML's (thickness monitoring locations) and surface preparation. Now the big question: What would be a acceptable tolerence on a repeat reading the day later? We all know that it is very difficult (if not impossible) to repeat the exact reading on old piping. Are there a paper available for guidance?
: Regards
: Poena (HPIA Site Manager)
------------ End Original Message ------------




    
 
 
Rohit Bafna
,
TCR Engineering Services, India, Joined Sep 2007, 18

Rohit Bafna

,
TCR Engineering Services,
India,
Joined Sep 2007
18
00:58 Jul-19-2008
Re: Online UTWT acceptable tolerences
You should look at Credo Soft which has a product for wall thickness measurement and recording. Visit http://www.credosoft.com/download/Wall%20Thickness%20and%20Anomalies.pdf

Look at the Credo PRO software at http://www.credosoft.com/products.htm

Our company, TCR Engineeeing (www.tcreng.com) can help you define an acceptable tolerence guideline based on your corrosion rates and material specifications.

Please note we at TCR work with PP SIMTECH to design and deliver RBI solutions to clients as well.


    
 
 
Ryan Burns
Ryan Burns
01:59 Jul-19-2008
Re: Online UTWT acceptable tolerences
----------- Start Original Message -----------
: We have a project on the go @ Engen Refinery, Durban, South Africa for online piping inspections in accordance with API570. Recently, we incorporated an audit system to verify the acurateness of the UTWT results. The idea behind the audit is not to target the qaulified NDE technicians, but rather to find better ways of repeating TML's (thickness monitoring locations) and surface preparation. Now the big question: What would be a acceptable tolerence on a repeat reading the day later? We all know that it is very difficult (if not impossible) to repeat the exact reading on old piping. Are there a paper available for guidance?
: Regards
: Poena (HPIA Site Manager)
------------ End Original Message ------------

Hello Poena,

I have never come across a paper on this, but I would be surprised if one did not exist. I believe the most practical approach is the one I was taught years ago by a very smart man and pioneer in corrosion survey development.We were able to go back to a vessel or piping component years later and, in a very low corrosion service, repeat the reading exactly, or +/- 2 mils. Some obvious things to consider are;
1- Use the same instrumentation between all UT data collection crews.
2 - Att techs should use the same exact calbration wedge and always do a two point calibration within the range to be measured.
3 - Use the same make of probe (dual element) with acceptable wear between crews. Use the probe within manufacturers specs, most say aove 120 deg F, a high temp transducer and/or delay line is required.
4 - Mark the TML points with indeliable paint. If you do a minimum scan along, say the extrados of an elbow, mark the exact scan area.
5 - Check the calibration frequently, especially if scanning as opposed to single point readings.
6 - Use a proper couplant, not grease or the like, as each tech will have different transducer application pressure.
7 - Record the temperature of the component at time of inspection. Proceduralize how elevated temp components are handled, either heating cal block, temp compensation, or standard ambiant cal with repeat UT done when vessel is always on or off line with a consistant temperature.

As I write this, I realize I could go on for a while....hope some of this helps, and if you do come across a technical paper on this please let us (the forum) know.

PS - Most sowftware (not just CredoPRO) with upload interfaces have a built in QA function of % to last reading. This is good, but proper procedures and trained techs is paramount.

Regards,

Ryan.


    
 
 
Arun
Arun
05:52 Jul-20-2008
Re: Online UTWT acceptable tolerences
We can do consultancy for this situation since I worked In brunei Shell facility for 5 years for doing TML UT wall thickness doing corrosion monitoring-Arunachlam.NDT level 3 , contact me at arun@cutechinspection.com-
---------- Start Original Message -----------
: Probably Mr. Dinesh Gupta, an ASNT Level-III in 7 methods could help you out. Mr. Gupta is based in India, but travels globally for such problems. You can contact him on guptadinesh1966@yahoo.com
: : We have a project on the go @ Engen Refinery, Durban, South Africa for online piping inspections in accordance with API570. Recently, we incorporated an audit system to verify the acurateness of the UTWT results. The idea behind the audit is not to target the qaulified NDE technicians, but rather to find better ways of repeating TML's (thickness monitoring locations) and surface preparation. Now the big question: What would be a acceptable tolerence on a repeat reading the day later? We all know that it is very difficult (if not impossible)to repeat the exact reading on old piping. Are there a paper available for guidance?
: : Regards
: : Poena (HPIA Site Manager)
------------ End Original Message ------------




    
 
 

Product Spotlight

Varex Imaging Large Field of View (FOV) Digital Detector Arrays (DDAs)

A larger FOV DDA can reduce the space and volume of the X-ray inspection system on the factory floor
...
, enable faster scanning times, better throughput and better resolution images at a lower dose. Customers can also save time and money. With these benefits in mind, Varex Imaging has designed a family of large FOV detectors (4343HE, XRD 1611, 4343DX-I, 4343CT) for our industrial imaging customers.
>

ISAFE3 Intrinsically Safe Sensor System

ISAFE3 intrinsically safe sensor system of Vallen Systeme is especially targeted at the petrochemica
...
l - as well as oil and gas transportation industry. The sensor system is designed for permanent monitoring or periodic inspection tasks. Sensors are available for different AE-frequency ranges optimized for corrosion and fatigue crack detection and other applications. The ISAFE 3 sensor system consists of an AE-sensor (model ISAS3) certified according to ATEX/IEC for installation in zone 0, gas group IIC, IP68, 20 to +60 °C, and a signal isolator (model SISO3) certified for installation in zone 2. An ISAS3 sensor can be mounted in atmosphere or submerged, e.g. in water or crude oil. It is supported by mounting tools for temporary (magnets) or permanent (welded) installation. ISAFE3 supports automatic sensor coupling test and can be used with any AE signal processor supporting 28V supply at 90 mA peak, e.g. Vallen Systeme ASIP-2/A.
>

SONOAIR - air-coupled Phased Array Ultrasonic Inspection System

For highly attenuating materials, the performance of the system is critical. The ultrasonic sensors,
...
the scanning area and the system settings should be flexibly adapted to the test task and the material. These high expectations are met with the new and modular testing system SONOAIR. With the world’s first air-coupled phased-array UT inspection system SONOAIR we developed a technology that works with up to 4 transmitter and receiver channels with freely configurable square wave burst transmitters as wells as low noise receiving amplifiers.
>

IRIS 9000Plus - Introducing the next generation of heat exchanger inspection.

Representing the seventh generation of the IRIS system, the IRIS 9000 Plus has nearly 200 years of c
...
ombined field inspection experience incorporated in its design. This experience combined with a strong commitment to quality and a history of innovation has made Iris Inspection Services® the undisputed leader in IRIS technology.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window