ASME BPVC Section I Power Boilers

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pat1027
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Re: ASME BPVC Section I Power Boilers

Post by pat1027 »

Miniature in ASME parlance is not the same as the live steam hobby would use miniature. ASME for example requires miniature boilers to be equipped with a minimum 1/2" NPS sealed safety valve and 1/2" blow offs. Applicable to a small or "miniature" boiler installed in a building but who would want to put 1/2" safeties and blow offs on a Clishay or 1" American? "Miniature" in the ASME code is on a different tier than a hobby locomotive boiler. The ASME has useful information but I would cringe at the thought of trying to apply it in whole to the live steam hobby.

Michigan's boiler agency also researched model boiler accidents and could find no record of explosion or injury. The boiler board of rules met with a group from the hobby who presented typical club inspection procedures, inspection records going back decades and an example of stress calculations for a model boiler. The chief inspector can out to a run day to observe club inspections. In the end the head of board of rules said the hobby was doing a fine job and to "keep doing what you are doing". We ended up with exempt from the main boiler code and with a small set of rules that pretty much mirrored what the hobby was already doing.
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gwrdriver
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Re: ASME BPVC Section I Power Boilers

Post by gwrdriver »

Covered.
gwrdriver wrote: Wed May 24, 2023 7:47 pmDick,
My recollection is that when referred to in code editions of the past, a "miniature" boiler was a different category of boiler, and the term didn't mean a model/hobby boiler.
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INGE
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Re: ASME BPVC Section I Power Boilers

Post by INGE »

I did send an email to ASME asking if hobby boilers, such as live steam locomotives, less that 12" ID, less than 125 psig, are governed by ASME Boiler and Pressure Vessel Code. They sent me a interpretation request form which is impossible fill out with out the Code to refer to. I called them by phone and was advised my question sounds like a consulting question, thus they cannot provide an answer.
steamingon
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Re: ASME BPVC Section I Power Boilers

Post by steamingon »

INGE wrote "I did send an email to ASME asking if hobby boilers, such as live steam locomotives, less that 12" ID, less than 125 psig, are governed by ASME Boiler and Pressure Vessel Code.

YES they are! This is found in the PREAMBLE Note 1, which states "Power hoiler - a boiler in which steam or other vapor is generated
at a pressure of more than 15 psi (100 kPa) for use external to itself.

There is no size limitation in this description.
steamingon
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Re: ASME BPVC Section I Power Boilers

Post by steamingon »

The only purpose of the Part in Section I of the code called "Miniature Boilers" is for the required inspection openings and piping connection diameters to be proportional to the size of the small "Power Boiler". Almost everybody thinks "Miniature Boilers" has to do with "hobby boilers . IT DOES NOT!
A "Miniature Boiler" is still a "Power Boiler" in which the limits specified in PMB-2 are not exceeded.
A "Power Boiler" is a boiler in which steam is generated at a pressure greater than 15 Psi
Marty_Knox
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Re: ASME BPVC Section I Power Boilers

Post by Marty_Knox »

The ASME code is a construction code. It is up to each jurisdiction, usually the state, to decide whether to adopt in all or part.
The miniature designation is for what I call 'laboratory' boilers, small boilers for experimental or test work.
Some states have exemptions for hobby boilers below a certain size. Alaska, Illinois, New York, and Texas all have exemptions. Some states will inspect non-code boiler - Maryland, Michigan, and Washington are 3 states that do. Some states simply ignore the hobby.
Rich_Carlstedt
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Re: ASME BPVC Section I Power Boilers

Post by Rich_Carlstedt »

From Marty
"Some states have exemptions for hobby boilers below a certain size."

yes, as an example, When I moved to Wisconsin 30 years ago, I was told the boiler code
did not apply to boilers with a Firebox grate area of 144 square inches or less ( 12" x 12' ie)

Rich
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Dick_Morris
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Re: ASME BPVC Section I Power Boilers

Post by Dick_Morris »

Some states have exemptions for hobby boilers below a certain size.
And in Alaska and other states with similar exemption language, a pressure of under 100 psi.

As my late lawyer friend said, "The law givith and the regulation takith away." My recollection is that the law in Alaska exempts hobby boilers, but the regulation defines them using the ASME definition for size and pressure for miniature boilers.
Last edited by Dick_Morris on Tue Jun 20, 2023 9:28 pm, edited 2 times in total.
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Bill Shields
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Re: ASME BPVC Section I Power Boilers

Post by Bill Shields »

Beat me to it :mrgreen:
Too many things going on to bother listing them.
James Powell
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Re: ASME BPVC Section I Power Boilers

Post by James Powell »

Thank goodness I live in BC. 22 sq ft and under exempt, unlimited pressure. :)
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NP317
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Re: ASME BPVC Section I Power Boilers

Post by NP317 »

Canadians are smarter...
RussN
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Bill Shields
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Re: ASME BPVC Section I Power Boilers

Post by Bill Shields »

have fewer lawyers per capita?
Too many things going on to bother listing them.
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