Revised boiler test code

I notice that the new revised boiler test code available on the Northern Fed web site calls for the superheater to be included in the repeat hydraulic test, "If Practical".

Please can someone explain the rationale behind this and what exactly is meant by "If Practical"?

I think that it should be possible to blank off the superheater but the amount of dismantling needed could be substantial.

Also when a superheater fails forward motion tends to cease fairly quickly but surely this is not normally a safety issue?

Anyone seen or heard of a superheater explosion....

Every now and again I read something here and my first reaction is to jump in with a comment. On this particular thread I have to be better than careful, due to my previous life as a committee member of what is said to be the premier organisation looking after the welfare of many of our clubs/societies. So in reply to 'fizzy's' question, no, but I did have a superheater let me down on my Pannier locomotive several years ago. All that happened was a decided lack of forward power, clouds of steam and a rapidly degrading fire. Oh, and a lot of laughs from fellow club members.

Well I assume the "if practical" bit will be up to the Boiler Tester to interpret & decide.

If you have four or five engines to test of a morning, it's one thing to hydralic test them by whipping out the safety valves and screwing in your test rig (together with a quick visual) and another thing altogether to try and remove (and blank) off the superheater.

But as this matter seems to rely on the discretion of the Boiler Tester, I supect that in practice it will not therefore be an issue for most people. I hope not, as unscrewing mine is a pain at the best of times and there would not be too much room to fit a blanking plug (at least whilst the boiler is still in-situ).

So I don't think it will be "practical" in most caes....and I very much doubt many BT's will want to do it. I'm not going to worry too much about this (nor debate the neccessity of it) until I actually get asked to do it by my friendly local BT!

Regards,

IanT

Must say that is the interpretation that hopefully many will put on the topic. Sleeping dogs and all that comes to mind. Plus of course the majority of club boiler testers are sensible people and do appreciate what is practical and what is not. Many if not all superheaters would require a good time preparing for this capping off, would make it even worse if the intention on the day was to follow up with a steam test straight after the hydraulic had been completed.

I agree with all this but it still doesn't provide the logic of why the test is included in the first place?

John B

I did question this during the consultation process, the reply I was given was that at the time of re-writing these codes the decision was taken to get the whole thing up to a standard that incorporated more of the PSSR 2000 regulations/guidance. The experts (x1) reckoned that the superheaters were to be included as they form part of the pressure system. They quickly found a reasonable/large number of club members throughout the hobby were set against this due to the comments listed above, so the term 'If practical' was included as a way forward. Surely it could have been worse, when it may have been considered that the entire pipework from the regulator, through the superheaters and continuing down to the steam chests and cylinder sets are, in theory and maybe in practice, part of this same 'pressue system'.

My own comment is, for what it is worth, let common sense prevail while it can, surely non of us are such idiots when it comes to the safety of others and particulalry ourselves! Perhaps when the next re-write takes place some of these high and mighty ideas can be struck out and a return to a more 'hobby' based attitude taken.

Edited By Heronsgate on 14/02/2013 11:17:09

Just noticed there is this that you can view to get a broader picture of what is behind this reasoning (?) however impracticable it may seem to many of us.

12/2/2013 Information sheet 'Safe Operation of Pressure Systems for the Model Engineer' added, see 'Information Sheets' Menu

This sheet appears on this website www.sfmes.co.uk