Hello All,

Just a point of interest, please....................

When using ultrasonic thickness testing machines for measuring boiler plate to support a 1,472 day inspection, what criteria, procedures, practices, etc. are used to conduct the examination ?

Thank you.

Respectfully,

Dave Griner

One of the things that I see several folks make a mistake on is firebox sheets. I see the UT reading taken between staybolts. The UT reading should be taken immediately adjacent to the staybolt head, as close as possible with the transducer. The area around the stays will corrode due to stress corrosion cracking, and may be much thinner than the sheet between the stays. Here is a photo of a cross section of a crown sheet and staybolt taken out of a traction engine, which was operating at 150psi until a leak was noticed.

Bottom of firebox just above mud ring. Boiler barrel at water line. Bottom of front tube sheet. Anywhere things were hung on the exterior of the boiler, you'll probably see the rust pit patches. Places around the firebox and barrel that are difficult to clean well during washouts...... all areas I've found trouble.

Kelly, if you have the time, can you walk him through how to set up and execute a proper 'death ray' analysis?

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I figured that somebody who knows more than I do would step up on this one...

Much as I hate to say this, the discussion board has slowed down considerably since the mods have (justifiably) tried to throttle down the trolling a few notches.

I’m mostly a diesel guy so I have nothing to add but I find technical discussions on steam fascinating. Hope this thread picks up.

The CFR requires inspection but doesn't tell you HOW to do it. Do you just want the numbers to equal the values which will pencil out well when calculating your Form 4 or do you want to know the truth? Nothing you prevents you from checking next to staybolts, just above the mudring, around blowdowns, or even arch tubes.
https://www.ecfr.gov/current/title-49/s ... I/part-230
It also requires the owner/operator to inspect tenders. Large shops had an entire department dedicated to maintenance and repair of tenders. Although I've never seen a tender come "unzipped", it could happen and it would never be at a convenient time or place. I've seen a lot of leaking slope sheets and weeping tanks though the years. 'T' iron and rods thin? Sides rotten at the bottom? Might want to use the UT while it's out of the box. Ever see a grid on a smokebox? You won't find much about them in NBIC or ASME documents because it's not part of the pressure vessel - but it is the only thing holding the pressure vessel to the rest of the locomotive. The owner/operator is responsible for a locomotive and tender which is safe and suitable for service. Lots of good reading here: https://www.govinfo.gov/content/pkg/GOV ... 1ee412.pdf

I’m with Kelly on this. Mr. Griner is someone I would consult if I had questions on the subject.
So I’ll add a question; does FRA require all tubes and flues to be removed at the 1472 day inspection, as I assumed, or is there an allowance for superheater flues to be left in and UT’d for thickness? I’ve recently heard some discussion of this.
Thanks.

Per part 230.31(b), as long as you can enter the boiler to thoroughly clean and inspect the interior and it can be proven that the flues are safe and suitable for service using an appropriate NDE testing method, then the superheater flues do not need to be removed. However, they do have to be removed if the FRA inspector or owner/operator considers it necessary due to identifiable safety concerns.

How many operations have been able to utilize this exception?

Ed

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I don't think Dave Griner would be asking at all if he weren't interested in other people's 'detail design' and methodology for this kind of NDT.

I have no experience in it other than from the armchair, so have nothing of any practical value to contribute.

"I would advise going with the truth, no matter how much more it costs."

Exactly! It's the right thing to do and nobody wins when something bad happens whether it is due to ignorance or willful noncompliance.

I've personally never done an ultrasound, but learning the right way to do it is what I am interested in.