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[Seacommander]

Hello,

 Advice and suggestions welcome....

 I have been approached and asked for advice on a French Anton steam plant. The unit was fitted in a model boat and went for the  boiler test, to enable it to run at the local lake, the boiler test failed. (brand new plant)

 I am advised that one of the tests completed, is that the boiler has to be allow to boil up until it blows off. At this point, the gauge on the boiler has to read the same pressure as the test rig and then show a rapid decline in pressure. On this occasion the boiler failed to do this the pressure either still rising or certainly not seeing the decline that the inspector required.

 I know despite all the jibes and jokes, we have to be safe, however in this case this was a 75 Birthday present for this chap. He has built it up and installed it into a krick Alexander and made a very nice job. His work is exceptional, after this episode he went home and shelved it. His wife has asked if I could shed any light.

 I know it's likely to be a bit of muck in the SV or something like that but has anyone else had problems..

 Appreciate any advice or help

 Cheers

 Mark

[derekwarner]

Seacommander......I find it surprising that the inspector did not offer constructive comment on a resolution to the issue

Steam relief valves are safety devices, if the 75YO owner or you are not sure how to hydrostatically set relief valve with water, the best bet is to discuss this with the same boiler inspector or for the owner to join a model club that has a number of members with steam vessels....

World wide....the model steam fraternity are helpful people with a common love...... steam.....Derek

[Seacommander]

Hi Derek,

Yes, my thoughts exactly. However I don't know exactly has gone off, I was not at the testing and was asked by the family for help, which I don't feel very well able to give, as I'm more into toy steam. However, I want to remain neutral at the lake but also help this chap. My feelings at this time are that I will suggest that he looks to get a new valve from Anton that is factory calibrated and that he also looks to wash the boiler out, then he fires it several times, before getting a re-test to ensure that it is working well. Just also wondered if it could be over gassed ?

Thanks for very helpful reply

Cheers

Mark   

[Jerry C]

Mark, there is a set of "regulations" that club testers are meant to adhere to with regard to model steam boilers. These are not the law of the land but are sensible safe procedures that have been worked out over many years which clubs and insurance companys have deemed to be a standard that will keep people safe.
  I don't have a copy to hand but from memory a safety valve should lift at a psi figure specified by the maker and, with the burner full on and the steam outlet valve shut, the boiler pressure should not rise more than 10% of the designed working pressure. eg., for a 60psi working pressure, the pressure should rise after safety lifts to no more than 66psi.
   I find it strange that a tester would say the pressure should drop. It may do so but doesn't, according to the rules, have to. I think maybe your friend has misunderstood the testers comments.
    Safety valves have been known not to perform correctly but not usually from new.
   I suggests he takes it back off the shelf and gets in touch with the supplier and give him a chance to rectify the problem.
Jerry.

[steam up]

I would advise that a re test is requested which he attends in person (he will learn a lot more this way).
The boiler pressure is not required to drop just not to rise 10% over the max pressure.

[Seacommander]

Hello,

Some very useful replies, all of which make sense and are constructive.

I now have a copy of the regulations, together with these posts, I'm that we can find a solution.   

Thanks to you all for you time and efforts in reply.

Cheers

Mark

Kind regards

Mark

[Klunk]

http://www.mpba.org.uk/PDF%20Files/Corrected%20Steam%20Rules%20Leaflet.pdf


If I remember correctly, all boilers are tested under air pressure up to twice the standard psi required with a blanking plug where the pressure release should be. it is then retested exactly the same with the pressure relief valve in, where it should blow at pressure plus 10%. depending on said pressure for the boiler. If the pressure valve has failed, it is normally only a few things, ie o ring failure, spring failure or incorrect spring setting for the pressure failure.
As opposed to a set of rules regulating steam, I could open up a can of worms here, but there are no regulations that actually state you need a boiler test! Even as said earlier that insurance and or clubs require this is tosh. there are no legal reasons to actually have the boiler tested! As most of the boilers that are used in model boats are low pressure. I would also say that as I have a steam boat I do have it tested every year as I have no idea what sort of damage could have been done inside the boiler whilst in storage!! As also mentioned safety is paramount and I FIRMLY BELIEVE IN THE VOLUNTARY CODE ADOPTED BY MOST CLUBS!! The above link, whilst a guide, is not fully up to date as I know they changed the rules again in testing boilers again!

[BarryM]

Testing pneumatically rather than hydraulically is asking for trouble.

Barry M

[ooyah/2]

http://www.mpba.org.uk/PDF%20Files/Corrected%20Steam%20Rules%20Leaflet.pdf


If I remember correctly, all boilers are tested under air pressure up to twice the standard psi required with a blanking plug where the pressure release should be. it is then retested exactly the same with the pressure relief valve in, where it should blow at pressure plus 10%. depending on said pressure for the boiler. If the pressure valve has failed, it is normally only a few things, ie o ring failure, spring failure or incorrect spring setting for the pressure failure.
As opposed to a set of rules regulating steam, I could open up a can of worms here, but there are no regulations that actually state you need a boiler test! Even as said earlier that insurance and or clubs require this is tosh. there are no legal reasons to actually have the boiler tested! As most of the boilers that are used in model boats are low pressure. I would also say that as I have a steam boat I do have it tested every year as I have no idea what sort of damage could have been done inside the boiler whilst in storage!! As also mentioned safety is paramount and I FIRMLY BELIEVE IN THE VOLUNTARY CODE ADOPTED BY MOST CLUBS!! The above link, whilst a guide, is not fully up to date as I know they changed the rules again in testing boilers again!

Klunk,
I suggest that you read the M.P.B.A regulations closely.

No where does it say that you have to test boilers or pressure vessels with air, they must be tested Hydraulically,
I.E. all air must be evacuated by water and then the test for a new boiler shall be 2 x W.P.

As Barry says you are in very dangerous ground testing by air.
For new comers to steam if under hydraulic test pressure a leak is found all that would happen is a jet of water would come out, with air the boiler can fracture causing damage to life and limb, so don't do it.

Klunk  if you think that test pressure are tosh just go to any insurance company and ask for cover and the first thing that they will ask for is a test certificate.
Clubs and associations require boilers to be tested in order to get cover for any accidents that may happen.

If you are not a member of any club you can go and sail on open water without a test certificate but any accidents are down to you for any claims against you.

George.

[Klunk]

I never read the actual document, I give mine to a proper tester who has worked on proper steam boilers all his life. If he says I need something doing to my boiler it happens. It was my understanding that they were tested under air pressure.
And at the end of the day it is a volutary code

[Klunk]

ps my boiler failed its first test for a small weep. I glad it was found as when we both inspected it we found several minor faults that would not have made the boiler fail, but would have over a period of time made the boiler impractical to run. I still have problems coming from a hard water area with scale, and getting clean water is a big problem! Any suggestions would help!!! At present im putting tap water through a britta water filter 3 times before I trust it!! And still i get scale!

[Netleyned]

Might be a voluntary code but if your insurer says 'Test Certificate'
then it needs to be tested.
A boiler doing a nasty on a well attended show (Wicky for instance)
could cause untold problems to the owner of the model, the organisers.
the lake owners not to mention the injured party.


Ned

[Klunk]

George please do not paraphrase me about my tosh comment. read the text and see that I firmly believe  in the the voluntary code. I preceeded that the comment by saying that 'I could open up a can of worms here' [/size].

[sparkey]

  I know some guys in our club distil their own,that way you have pure water,can't be be hard to knock up a little unit from copper pipe and an old kettle there again I don't know much about it,or maybe be able to buy some from a chemists,Ray.  

[SteamboatPhil]

I would like to point out that the testing of pressure vessels as defined by the MPBA are up to date and are addopted as regulations, you must have a test certificate to enter any MPBA event.
As has been stated, the first test on a new boiler must be to twice working pressure, then following tests (every two years) is to 1  1/2 x working pressure, and are hydraulic tests.
The southern federation rules on boiler testing are slightly different, as they have a steam test as well (but they are mainly for the Loco chaps) although some clubs have addopted them.

[Geoff]

Just to add my opinion:
 
1) If you belong to a club or the MPBA they typically require a test certificate as when you enroll with the club you accept and agree to abide by their rules. This also ensures insurance coverage if something should go wrong.
 
2) There is the 3 bar litre rule which effectivley means small boilers are not legally required to have a boiler test certificate. This means you can run on any public facility/park that you want to without a certificate. Believe this is European law which overides UK law.
 
3) Private facilities/shows can do what ever they want and would typically require a test certificate if you want to sail as part of the show.
 
4) Most household insurance covers you for hobbies provided the boats/planes are not over a certain size. There are no qualifications to this if I recall correctly as European Law applies per the 3 bar liter rule. If it is not excluded it is covered and there is case law to support this.
 
5) In practice this means even if you are a club member and sail on a local park lake you will need a boiler test certificate if sailing as a member, but if sailing as a private individual, you do not!
 
6) I have done Google searches on model boiler accidents and there is very little if any information on model boat boilers. Steam traction engines and train engines are in a different catagory alltogether due to the higher pressures utilised. Having said this I am aware of two boat accidents - one where the owner fitted the wrong safety valve (wrong thread) so it blew out but no great harm done and the other was a gas leak which set fire to the boat and burned out the steering servo. It stopped at my feat so was very simple to put out the small fire.
 
7) There are many people who seem to think a small boiler is like a bomb. It is not. Cheddar models once tested one of their boilers to destruction on steam and all that happened was some buldging and then a water tube leaked steam onto the burner and put it out. No explosion.
 
I think they are very much less dangerous than people think but neverthe less it is good practice to look after them and have them tested from time to time as no one wants any accidents.
 
9) I await the ungodley to pounce!
 
Cheers
 
Geoff
 
 

[KBIO]

Hello!
Do I dare??
Geoff, I agree >100% on your 9 points!
We have the same on this side, concerning the regualtion. Although, we are not so much "intoxicated" with test certificates.
Our only "Strictly forbiden" is concerning the use of Propane. This is a "NO-No", but........
Always heard of danger of explosion, but this is like the Lockness monster, we never seen it (Exept Ooyah maybe! Or me when I get back late, from the pub! )
Same with the use of the water. A lot of blabla,, when simply filing up a can with rain water is the ideal.
Still, I've heard some people scaring acid rains! We'll never change some!
The best water is at the spring, when it is cristal clear and there is no bug in it.

9) I await the ungodley to pounce!  Let's wait together.
Cheers.

[SteamboatPhil]

Opps the ungodly gets close.
Geoff is correct in all except the 3 bar litre rule, this maybe the case in Europe, but it is not the case in the UK and does not exceed certain guidelines (and some would say rules ) that we have in this country.

As has been said it is what the clubs rules advise that you have to adhere to, the MPBA does not at present work with the bar litre chart, so as has been mentioned you would need a boiler certificate to enter their events.

Also as Geoff has said there has been no accidents involving model boat boilers that have ever caused injury, just as has been said a few simple failings (which is all they really are) I have seen the odd gauge glass go (happened to me, quick bit of steam, flame put out,)
I test all my boilers to 400 psi as for me there is no point in messing about (working pressure is 120) and have never had a problem, my grandfathers and my fathers boilers are tested to the same (its the way they taught me) and all are still going strong, and 2 of them are over 60 years old.
Its is important to point out that most "failings" pond side are fittings, so not only should you test your boiler, you should check it and your fittings regularly

Onward chaps 

   

[Geoff]

From my reading the 3 bar litre rule does apply in England but many, if not most clubs, and associations choose not to subscribe to this, which is their right, so as a club member or association member you need to comply with the rules, but if sailing in a private capacity you are fine if under 3 bar litres.
 
This of course does not touch on wheter this is adviseable or not, and/or deemed not to be good practice.
 
I guess the point being if challenged on a public lake you do not need a boiler test certificate if under 3 bar litres.
 
I Googled this before I replied and everything seemed to confirm my findings but would be interested to know if this has been overidden in some way when sailing as a private individual.
 
On a sader note I think England is part of Europe so we have to obey their laws unless we leave !
 
Cheers
 
Geoff
 
 

[GAZOU]

Except for of the puppet theatres which fill the tank with gas the cigarette in the mouth I have never seen problems here in EUROPE.
And I have never heard about boiler which explodes.
Boilers deformed yes, but which explode not.

SteamboatPhil can you say to me in which continent is the UK ?

[SteamboatPhil]

Silly me, should have said the continent...   .just cannot get the hang of this Europe thing