ASME BPVC Section I Power Boilers

[steamingon]

Hello,

The ASME code has to be adopted by each state in order to become law. Once it becomes law it shall be available to the public. Hence With the age of the internet it is now available on line and you can download a copy. However all the information you need (other sections of the code) is not available yet.

Addition information required such as;

Allowable Stresses are found in Section II part D

Material Specifications are found in Section II part A Note, some piping requires a manufacturing tolerance to be deducted from the nominal thickness
before using it in calculations.

Section I Power Boilers can be downloaded here; https://archive.org/details/gov.law.asme.bpvc.i.2010

[INGE]

I believe the ASME has elected to not govern miniature boilers by the code. The threshold for many states is greater than 12" id for the code to be applicable, and state inspections be required.
ASME does not provide the code for free, current copies must be purchased. Older versions might be out there for free.

[Bill Shields]

There are quite a few States that inspect our boilers.

MD (where I live but do not run my steamers) is one of them.

[Dick_Morris]

The last time I looked into it, miniature boilers were covered by ASME, but in a different section than power boilers.

The reference above isn't to the current edition. Per a quick web search, "The current effective version of ASME Boiler, Pressure & Vessel Code (BPVC) is the 2021 Edition. However, the 2023 Edition is already available for pre-order."

[gwrdriver]

Dick,
My recollection is that when referred to code editions of the past, a "miniature" boiler was a different category of boiler, and the term didn't mean a model/hobby boiler.

[Dick_Morris]

The image shows coverage in "Part PMB, Requirements for Miniature Boilers" in the 1995 edition.

Although part PMB applies (or did apply) to boilers in the size range suitable for a 1-1/2" or 2-1/2" scale locomotive, the code isn't that practical for those at the smaller end of the 1-1/2" range. It requires 1/2" NPT safety and blowdown valves and either two or three (depending on boiler size) 1" threaded brass plugs for cleanout.

Where a code boiler is required by the state or local authority, I believe it would either need to be covered by the miniature or power section, depending more on the pressure than the size.

Several states exempt boilers meeting these dimensions from being covered by the ASME code, but in at least some states, even the exempt boilers require a 1/2" NPT safety valve and limit pressure to 100 PSI. Other states are more lenient.

My recollection is there is also an issue with the stubby Kunkle 1/2" ASME code safety valves that we all know and love. The are actually only approved for unfired vessels. ( I understand that at one time the same valve was approved for fired vessels, but that was before my time, and I've been around for quite a while.)

[Bill Shields]

All of which is why I do not run in MD
.
A friend who is a NIB inspector there commented to me on year that all of the Gauge 1 locos running at a show were in violation...only 1 safety and an illegal one at that.

He makes sure that he never visits the gauge 1 operation area for fear that someone will get a picture of him observing that might get back to the people he works for and be forced to call for compliance.

If he "never sees" the gauge 1 stuff, then he can plead ignorance.

Come right down to it, how many 2.5" and 3.5" gauge locos have 2 safety valves? Many of the smaller British designs have only one ..and are therefore technically illegal to operate.

[gwrdriver]

Early in our club's history Tennessee had a really hard-nosed, by-the-book inspector. He would never accept that a few amateur builders could produce and operate safe boilers, of any size. A generation later the inspectors would occasionally come to our meets, but not to inspect boilers. They wanted to see the trains run! They said we aren't worried about you guys, we have much larger fish to fry.

Now we have code exclusions, but as old inspectors move out and new ones come in the attitude toward inspection and compliance is bound to change to some degree. I don't know what our current inspector's attitude is, but I think PontiacGuy will know.

[Bill Shields]

I like the miniature boiler pressure limit of 100 psi

How many times do I see our model boilers with the safety valves set at 125psi in complete ignorance of the rules.

I have tried talking to folks about it, but gave up decades ago.

My point is that if someone were to get hurt and the club accepted inspection of a 125 psi operation boiler, some lawyer would have a field day with it.

[INGE]

I sent an email to ASME asking about code applicability to hobby boilers. If they respond, I will advise.

[Marty_Knox]

I sent an email to ASME asking about code applicability to hobby boilers. If they respond, I will advise.

Each jurisdiction, usually the state, decides what rules apply. In Illinois, New York, and Texas there are exemptions for Hobby Boilers based on size.
Maryland, Michigan, and Washington will inspect non-code boilers.

[Pontiacguy1]

I don't know what our current inspector's attitude is, but I think PontiacGuy will know.

I also deal with pressure vessels in the state of TN in industrial applications for my last 2 employers. You want to know a secret? I have Never met a State of Tennessee Boiler/pressure vessel inspector. Not one. The way the state of TN now handles their pressure vessel inspections, at least for the last 15-18 years I've been dealing with them in industrial applications, is to let your Insurance Company do the once-every-two-years required inspection. Your insurance carrier is the one on the hook monetarily if a failure occurs, so they have a vested interest in your pressure vessels being safe. Thus the state will accept their inspection.

Your insurance carrier will have a certified pressure vessel inspector who will come to your site, look at your pressure vessels, note that they are still in original condition and have the original builders plates on them, and sometimes they will manually pop the safety valve on them to insure they are not stuck. They will check your operating pressure and make note that both it and the safety valve relief pressure are at or lower than the max pressure rating of your vessel. They will ask you about blowing down or draining the water out of tanks, and may ask a little about your PM program. They will then submit their inspection report, however brief, to the State of TN, who will then issue you an invoice for each of your pressure vessels. Upon payment of the invoice, the state will send you your Certificate of Boiler Inspection. Man I love Tennessee.

The inspector, who happened to be here just this week, in conversation told me that states are all VERY different in what they want and how frequently you have to inspect. Some states are 3 years, some are annually, some are 2 years, etc... He covered most of the Southern states (Tennessee, Alabama, Mississippi, Georgia, Kentucky, Arkansas, maybe the Carolinas too).