Russo Loco Wrote:
> So where did the 15 Year rule come
> from?
First of all, remember that the requirement to remove the tubes has nothing to do with the condition of the tubes, it is to allow an inspection of the interior of the boiler barrel, much of which can’t be seen or cleaned with the tubes in place, and is something you really, really, really don’t want to have fail.
I understand that it was a compromise reached after long discussion within the “Engineering Standards Committee” a.k.a. “The Gods of Steam” consisting of several CMO’s of steam operations, and representatives from the FRA, NBIC, insurance, and engineering companies, who wrote the current steam rules in the 1990’s.
Under the old rule, your flues had 48 months of service life to be used within a maximum of 60 months’ time before they had to be removed, unless a one year extension was granted by the FRA. This rule was written when steam railroading was a year around business.
Operations today are seasonal to occasional as a rule, and the Gods wanted to allow for that, and also allow for heavier year around use. So, if you run your engine 7/365, the current 1,472 day limit will allow to have a tube life of 48 months just like the old rule, however, if you steam your engine 98 days per year or less, the previous limit was changed from five years to fifteen years to give the operators much relief compared to the old system.
Why fifteen years? As I said that was a compromise reached to try to balance economic relief with the consensus that fifteen years was the limit that was felt that the boiler barrel should go without being inspected. As much as anything, this was a result of the lack of control over various operators habits and practices, in that you can have an operator that only operates occasionally, but he leaves the boiler full of water in between operating days, so the boiler can be rusting away even though it is not being used. It was felt that it would be impossible to enforce any standards regarding storage and water treatment among the many operators out there, so the result was an absolute limit on the amount of time that the barrel could go without being inspected.
When in doubt the safe course must be taken.
