Oregon boiler code

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Mar 22, 2013
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Having read the state boiler code topic, I just had to e-mail one of Oregon's boiler inspectors. I will let you know the reply. Here is the text of my e-mail:

Hi Susan:
I chose you among the listed Boiler inspection staff because you were the only one with a 541 phone prefix, and I am in the Rogue Valley. I am just getting started with hobby machining, and intend to build very small toy steam engines using a mini lathe to machine parts from brass, bronze and steel. We're talking pistons .375 inch in diameter here, and engines powered by simple copper pipe "pot boilers" of 3 inches in diameter or less, fueled by a denatured alcohol burner.
In discussing engine making on one of several forums dedicated to the hobby, the question has come about state statutory requirements for hobby boilers.
Looking at ORS 918-225-0390 (1) (d), it seems even the tiniest hobby boiler needs an ASME-approved safety valve (to my knowledge tiny valves for hobby boilers running at, say, 30 psi and approved by ASME do not even exist), water level indicator and pressure gauge, and under (1)(e) must be inspected and approved prior to operation.
Knowing the public interest in promoting safety, this still seems like a lot for the state to ask of a hobbyist building a toy steam vessel not much larger than two D-cell batteries.
Have you or any of your colleagues actually inspected such boilers? Frequently? Are you aware of an ASME approved safety valve of a size proportional to such small vessels?
Sorry you had to be the one to get this question; my sense is that boilers this small most often just go ignored and no one is the worse for it. Sometimes statutes written in legislative chambers fail to consider just how far they might reach.
I would appreciate any wisdom you may have on this.
Bill Powell
Been using Kunkle safety relief valves. Visit their site .Model 30 may do.
The lowest is 60psig set pressure. Resetting to 30 psig voids ASME/UL or NB approval.
Design bolier to 60 psig may be good idea.

In Australia,we have approved voluntary inspectors to check design drawings,inspect boiler prior to hydro test. With their approval,model steam trains are permit to operate at all train clubs.

As for my own,I satisfy myself with hydrotest of mini boiler and safety valve. Model Steam Plants are operated at home.

TubalCain,Wisconsin,USA may have good advice to offer.

Before retirement,I ran a plant making ASME code receivers and Non-code receivers too for twenty years with no accidents.I take no short cuts.

Gus Teng.
The applicable Oregon boiler code section is "Rule 918-225-0390 - Hobby Miniature Steam Boilers."
Here's the reply I got today:


Your little steam boilers are EXEMPT!

Rule: 918-225-0390:

(a) hobby only
(b) inside dismeter less than 12"
(c) working pressure less than 100 psi

Life is good.

Susan E. Brown

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