[Steam-engine] lap seam calculations

[Dan Donaldson]

    I am new to this mailing list and I am glad that this topic has come up.
I am thinking about buying a traction engine (my first) and I am trying to
determine what I may need to do to make it acceptable to run at shows. I
know that I will have to replace a portion of the wrapper and I would like
to also replace the front tube sheet. My question is, if I replace the front
tube sheet should I go ahead and replace the lap seam barrel with a full
penetration, butt welded 3/8" thk barrel? Would I then be able to operate
the engine at 150 psi in states like Maryland assuming the rest of the
boiler is in good shape? In other words does a new, butt welded barrel
eliminate the problem of the lap seam?

Dan Donaldson


----- Original Message ----- 
From: "Ken Majeski" <fuller_johnson1 at msn.com>
To: <steam-engine at lists.stationary-engine.com>
Sent: Monday, July 12, 2004 6:03 PM
Subject: RE: [Steam-engine] lap seam calculations


> Well.... You are asking for calculations on the Barrel while giving us
> firebox measurements. If I run you firebox thickneses and staybolt pitch I
> come up with about 111 psi with a safety factor of 4. This will depend if
> the .310 reading is just a localised pit I can see where you could get 125
> psi.
>
> Now a lot of states have adopted the NBIC appendix C and they allow a
joint
> efficiency of .74 for a double riveted lap and .58 for a single. Wisconsin
> never did penilise a small lap seam but we currently have a rule limeting
> lap seams over 36 inches in dia to 15 psi. Butt strap seams are allowed a
> joint efficiency of .82 for a double riveted butt and .88 for a triple.
If
> you have good material thickness on your barrel I see no reason to be
afraid
> of 125 PSI.
>
> Minnesota did have the 100 PSI lap seam limet but due the the efforts of
the
> Minnesota Steam Engine assoc they got that changed and also can run lap
> seams over 36 inches now...
>
> I would recomend that you and your friends form or join a group as they
will
> listen to many people where just one or two will get no results. So far
the
> groups in Wisconsin and Minnesota seem to have a good working relationship
> with the inspection dept.... But lets Face It... If you have a Bad Boiler
> you are in Trouble...
>
> I am in the middle of this now as I am doing UT on my 24 Minnie and doing
> the calculations on it. What a Pain trying to lay out the grid and miss
all
> the castings ect as much as I can. Of course all this has to be reviewed
by
> the state inspector.....
>
> Ken Majeski, Ellsworth Wis. Case Steam Engine, Minneapolis Steam Engine,
> Rumely Oilpulls H, F, & R. Website, Http://www.pressenter.com/~kmajeski/
>
>
>
>
>
> >From: <steamman at ptdprolog.net>
> >Reply-To: Steam-engine mailing list
> ><steam-engine at lists.stationary-engine.com>
> >To: <steam-engine at lists.stationary-engine.com>
> >Subject: [Steam-engine] lap seam calculations
> >Date: Mon, 12 Jul 2004 12:05:28 -0000
> >
> >Engine friends,
> >
> >I just came from a show in Maryland. Spent 2 hours with the Chief
Inspector
> >and his inspectors going over the interpretation of their antique boiler
> >code. I was limited to 100 lbs. operating pressure because of my lap seam
> >boiler. In PA I'm allowed 125 lbs.  They refer back to the 1971 code for
> >new
> >construction of lap seam boilers. They will not even do any calculations
> >for
> >a lap seam boiler, they flat out say 100 lbs.
> >
> >I'd like to know if anyone can calculate the difference from 125 lbs to
100
> >lbs for a double riveted lap seam, What I'm really after is just how safe
> >is
> >100 lbs vs 125 lbs.  My last ultra sound on my crown sheet last year was
> >.365
> >around the fusible plug and found the lowest to be .310 in the rear left
> >corner of the crown sheet. My stays are 4 15/16"x 5". It's a 1909 Frick 8
x
> >10 and I very rarely work the engine. I ran a sawmill, thresher and a
rock
> >crusher once. I run a baker fan every so often for 15 minutes or so.
Other
> >than that I pull a sled just for show.
> >
> >Lets here everyone's thoughts and comments
> >_______________________________________________
> >Steam-engine mailing list
> >http://www.stationary-engine.com/mailman/listinfo/steam-engine
>
> _________________________________________________________________
> Is your PC infected? Get a FREE online computer virus scan from McAfee®
> Security. http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
>
> _______________________________________________
> Steam-engine mailing list
> http://www.stationary-engine.com/mailman/listinfo/steam-engine
>