I'm hearing through the grapevine that the FRA has been reviewing submitted Form 4's in Washington. And that one operator has been told to operate at a lower pressure as a result of this review. I have talked to our regional MP&E inspector and he knows nothing about this. Does anyone have any first hand knowledge of this? Or is this typical rumor mill stuff?

Thanks,

G. Mark Ray - TVRM

TVRM Shop Updates
aw90h@cs.com

Dear Mark:
Of course all of the new Form 4s are being reviewed. It would be rather pointless for the FRA to have us do all of these measurements, analisis and calculations and not check our work.
One of the main purposes of requiring a brand new, real time, complete analisis of our boilers was to determine whether or not they are safe to operate. The boiler's operating pressure is determined by the person signing the form. Since it is not a requirement that this person be an M.E. (although most people use one), it is logical for someone to check the calulations. That someone is an M.E. at the FRA named Gary Fairbanks (occationally assisted by other M.E.s).
If, for example, a Form 4 is submitted which shows the stress on a staybolt to be in excess of 7500 psi (49CFR part 230.25), then of course the Form 4 will be returned. The operator can make a repair or lower the pressure at his option. When we "ran the numbers" on our No. 40, we found that when the locomotive was constructed in 1920, no allowance was made for wastage of the door sheet. In other words, as soon as the door sheet wasted .001" you no longer had a safety margin of 4. Well, when we did the ultra-sonic measurements and calculations I was not too pleased. The sheet had wasted over the years and to meet the criteria of the new rules we were going to have to change out the door sheet or reduce the operation pressure. We chose the later to stay in business and plan to make and install a new door sheet (3/8" rather than 5/16") this winter. We will also install half side sheets, not because of wastage, but because we have had cracking out of staybolt holes: the side sheets are telling us that they are tired and want renewal. (Sorry, I digress).
The point is: having someone else look over our calculations is a good thing. It insures that they were done correctly (proper formula, accurate math, completely filled out form)and nothing overlooked.
J. David

jdconrad@snet.net

I've often wondered if renewed firebox and boiler segments would be better if made out of thicker steel. Say, if the original was 3/8" thick, would 3/4" be better, or would that place undue stress on the original segments that were still original thickness?

Minature live steamers, whose boilers would often scale out to 3" thick if made to 1:1 proportions, seldom have boiler explosions, even though they often run out of water.



ryarger@rypn.org

>The point is: having someone else look over
> our calculations is a good thing. It insures
> that they were done correctly (proper
> formula, accurate math, completely filled
> out form)and nothing overlooked.
> J. David

Absolutely. Due to the volume of applications and submissions, FRA now has 2 M.E.'s reviewing all submissions. As one might expect, nearly all submissions are complete and the numbers check out. There have been a few, however (and FRA, correctly, won't say who they are), that were incomplete (not all the numbers filled in or the numbers didn't add up; no UT survey was done; no interior and exterior inspection was done; an old Form 4 was copied and submitted as new, etc.), or other problems.

From what I can determine from my contacts at FRA, the agency is working with the operators to get problems corrected so they can operate, except in the cases where it's obvious that the UT survey and/or calculation work wasn't done properly or wasn't done at all. In those cases, the engine won't run until things are right.

And there will probably be one or two that will try to put something over on the Feds.

A few months back, the Federal Register contained a formal waiver request by a railroad which had missed the deadline for filing a request for special consideration (grandfathering) by more than a year. According to the waiver request and the supporting material submitted with it (it's in the FR), they had not done any of the work required to receive the special consideration, and they did not submit a new Form 4; they submitted a copy of the locomotive's original Form 4.

AFAIK, this waiver request is still pending (I have not seen any notice in the FR of it being either granted or denied, but I might have missed it), but personally, based on the info in the waiver request as published in the FR, I don't see how it could be granted.

Anyway, things like this are why FRA is going over each one thoroughly, as they should, IMO.

> I've often wondered if renewed firebox and
> boiler segments would be better if made out
> of thicker steel. Say, if the original was
> 3/8" thick, would 3/4" be better,
> or would that place undue stress on the
> original segments that were still original
> thickness?

> Minature live steamers, whose boilers would
> often scale out to 3" thick if made to
> 1:1 proportions, seldom have boiler
> explosions, even though they often run out
> of water.

You answered your own question, Bob. Steel thicknesses for boilers and fireboxes were not chosen randomly, and usually, thicker is not better. In some of the 300-pound boilers, if you run the numbers, a mere 1/32" increase in firebox sheet thickness changes the stresses in other parts of the firebox and the staybolts by around 20%.

In large engines, they were also using the thinner steels to save weight, and during the war, to save steel. but suffice it to say that beyond a certain point, heavier steel creates new problems rather than solving older ones.

Everything is a compromise.

> Minature live steamers, whose boilers would
> often scale out to 3" thick if made to
> 1:1 proportions, seldom have boiler
> explosions, even though they often run out
> of water.

Don't kid yourself, minature engines, if not properly cared for, can go POW as easily as their full sized brothers. At a garden scale convention I attended a number of years ago, I heard a bang coming from the area of the demonstration tracks. I looked over just in time to see someones pride and joy making a graceful arch toward the 20 foot ceiling of the convention center.

ironbartom@aol.com

Older locomotives, like the bridges and other structures built in the 'teens and twenties, tended to be a little bit overdesigned and overbuilt. If you run the numbers of some engines of that era, you find they left the factory with a factor of safety of 4.8 or even 5. That left a lot of allowance for corrosion and wastage over the years.

More modern engines, especially those with high-pressure boilers, were designed and built much closer to the margin. There were locomotives that left the factory in the 1930's and 1940's with a factor of safety of 4.2 or even 4.1; that means there was very little, if any allowance for corrosion or wastage before the FS fell below 4.
I've heard stories that Baldwin and Santa Fe locked horns over some of the 4-8-4's because the roof sheet thicknesses were right on the line for a FS of 3.99 or 4.0, with no allowance at all for corrosion and/or wastage, so Baldwin refused to sign the Form 4's for those engines; the Railroad signed them themselves.

Back then, a locomotive never had to be resurveyed and recalculated as they do now, and that probably resulted in many locomotives operating at an FS 3.9 or maybe even less during their service lives.

Today, if one finds oneself with such a boiler, the choices are to fix it, derate it (which, within reason, is an acceptable fix), or park it.

> Dear Earl:

An interesting aspect of the application for waiver is that they stated that they were unaware of the new rules.

While they might not have ever recieved an engraved invitation to comply (no one did, not even me), I spoke to them at length on the subject on two occations. They felt that they shouldn't have to comply because it was a new locomotive and that they couldn't afford to do the work. This same group tried to get a waiver from doing a flexible staybolt inspection (old rule 23). When they did the inspection they found several flexis that were loose (not carrying their load), I am told that these were replaced.

When we were working on the new rules, we discussed the fact that there were several new boilers (some complete new locomotives) and decided that it was better to have the rules apply to everyone than to set a precident making new boilers somehow "special".

J. David

jdconrad@snet.net

> Minature live steamers, whose boilers would
> often scale out to 3" thick if made to
> 1:1 proportions, seldom have boiler
> explosions, even though they often run out
> of water.

Having built a fair number of boilers for live steam locomotives, I have several comments to make. First off, I build Small boilers, not miniature boilers. While many builders try to duplicate the external appearance as close to scale as possible, live steam boilers are not built to scale internally. We do not use scale coal or water. If the typical live steam boiler has the equivalent of a 3" thick plate, it is also running a pressure equal to a full size pressure of 1,000 PSI. All the tubes would be the equal of Superheater flues, 5" diameter. A typical 1 1/2" scale locomotive boiler that I build has 1/4" thick side sheets, 3/8" thick tube and crown sheets, 1/2" diameter stays on 2 1/2" centers, and 25 5/8" OD tubes. I use Pressure Vessel Quality Plate, either A285 GrC, or 516 Gr70. Welding is usually done with E6010 electrodes for the root pass, and E7018 for the filler and cap passes. I run the stress calculations on the shell, the stays, and stayed surfaces. While some may say these are overbuilt, I am comfortable running them at 125 PSI. Plus, most National Board Inspectors are comfortable with them because they are familiar with the materials and construction. Many live steamers install fusible plugs.
Picture the way live steamers usually ride behind their locomotives - don't you think we have a lot of incentive to have a safe boiler?

Martyhuck@aol.com

One of the other factors, not really mentioned, is that beyond a certain thickness the metal will begin to inhibit rapid thermal transfer, creating internal stresses in the sheet itself.

BUT, if what was originally used was minimum thickness, then new sheets with an additional 1/16 or even 1/8th MIGHT not be a totally bad idea. Especially if you are replacing an entire crown or firebox, just crunch the numbers first.