NDT for Reformer Heater Tubes 1

[0707]

I would like to know from forum experience about some up dated inspection techniques to help us to estimate the remaining life of the reformer heater tubes. We have a heater 10 years old and we are going to have a shut down and we would like to prepare a NDT planning so that we can collect some data to estimate de remaining life of the heater tubes.

Thank you for your empathy

Best regards

Luis Marques

 

[metengr]

What is the tube material(s)?

You might be better off removing tube samples from targeted locations in the reformer for metallurgical analysis in addition to determining tube wall thickness.

 

[stanweld]

We tried magnetic techniques to determine the percent of the wall subject to carburization on HP modified pipe. It didn't work. Some of the modern EC test methods may now work. I advise that you contact a provider and make some measurement on tube samples where the carburized layer is known materials.

When replacing tubes, we measure the carburized layer and remove additional tubing until an acceptable remaining non-carburized wall is found.

 

[sk10009]

I'd like to recommednd ECT or sample.
Sample is best way to check the microstrcture.

 

[0707]

Tubes material is centricasted tubes 25Cr35NiNb.

Have you eared about the techniques bellow?

• LOTIS® Laser-based Internal Inspection Technology

• MANTIS™ External Crawler Inspection Technology with Eddy Current

• LifeQuest™ Reformer Remaining Life Assessment Solution

I Google and I found the site bellow from Quest

http://www.questintegrity.com/

Let me know your opinion.

Lm

 

[rustbuster]

Quest does have some good EC tools, there are others as well.

 

[0707]

Hi

rustbuster please share!

Thank you

lm

 

[rustbuster]

Here are some links

http://new.api.org/meetings/proceedings/upload/Reformer_Tubes_Tim_Hill.pdf

http://www.ndt.net/article/mendt03/shannon/shannon.htm

 

[0707]

Thank you rustbuster!

I already knew your links anyway I give you a star for the emphaty

regards


lm

 

[moseley]

0707,
I am a Welding Engineer for the largest and oldest Exchanger company and we routinely use IRIS inspection techniques for our inspections. Copy and paste this link to your Internet Expolorer bar for more information. I would highly recommend this method for your application, you will be very happy with what information you get in return. Hope this helps, good luck.

http://www.techcorr.com/services/Inspection-and-Testing/IRIS-Tubular-Testing.cfm

 

[AdrianoPL]

0707,
During the last turnaround maintenance (TM) we had performed LOTIS Ins. by Quest.
As far as I know Quest is performing this kind of inspection only during catalyst exchange by Johnson Matthey.
We also ordered LifeQuest remaining life assessment. Quest performed this raport 2 months after LOTIS Inspection (it was according to schedule).
The assessment was done professional, and right now according to it I'm ordering few reformer tubes for the exchange in the next TM; the ones that will be removed will go on for the destructive tests.

From my experience I can tell you that LOTIS inspection and Life ass. by Quest Group was very satisfying for me.
But you have to remember about one thing - the best way to know the condition of reformer tubes is to do LOTIS inspection starting from the tubes installation and during each TM (or when you change catalyst).

Regards.

 

[Metaljon]

Using the Quest system you would need to coordinate this with the Catalyst removal as it requires internal access for the scanning probe. Removing samples would be nice but probably not practical without scrapping some of the tubes.

We normally do a diameter survey of all the tubes using a pi tape at 1 m spacing. Pi tape measurement allow accurate measurement provided tubes are reasonably clean on the exterior. This gives an indication of how much strain has accumulated in the tubes and distribution along the length provided you know the original dimensions. Also from the distribution of strain it is possible to see where the hottest parts of the reformer tubes. With repeat strain measurement at subsequent outages it is possible to use this data to do a remaining life predictive model. Combine this with the LOTIS system results at a future outage should give you a reasonable life prediction. I would recommend that replication on the pigtails and outlet header is also undertaken.

Eventually when the tubes get replaced destructive examination is recommended to verify level of damage through wall.

http://nz.linkedin.com/pub/jonathan-smith/39/25/589

 

[Mally65]

HI, Quest have MANTIS as well for when the catalyst does not need removing. This also has eddy current device on.