What is the best solution for a Boiler

[withnail]

I have a project in mind to build a narrowbaot powered by a small steam unit if i can find the engine plans.

the engine i had in mind was 4" diameter radial steam and if remember correctly the unit worked of fairly low pressure.

Would it be safe to construct a boiler, with saftey valve etc. from brass plate and brase the endssimilar to a mammod or to buy a prefabricated boiler. I presume these are pressure tested.

If i need to buy a boiler does anyone have any suggestion.s

Tanks

[crash93]

Try http://www.maccsteam.com/they make some nice boilers that seem to work well and will build to your dimensions. i would think twice about trying to build your own boiler until you know what you are doing and you are aware of the hazards.

Peter

[bogstandard]

I hate to piddle on peoples dreams, but sometimes it has to be done.

You mention things like 'small steam plant', '4" radial engine' and 'brass boiler'.

I suspect you were brought up with, or are interested in what the collectors call 'Toy engines'. Mamod, Jenson and Wilesco spring to mind.

Operating steam plants in a public place, rather than in the confines of you own home, opens up a minefield, where legislation and pitfalls abound.

There is a great difference between the brass boilered 'toy' steam plants, and the specialised 'model' engines and boilers that are used in model boats by todays enthusiasts.

People will help as much as you want, if you are willing to take advice on what you really require, rather than what you think you need.

I will give you the first main bit of advice. Totally forget about the brass boiler concept. The material is just too unstable for public use.

John

[andy]

What is the best solution for a Boiler?

Mine!

I somewhere made a short description in this forum.

Andreas

[kno3]

...
I will give you the first main bit of advice. Totally forget about the brass boiler concept. The material is just too unstable for public use.

John

Come on, there are several steam engine makers (German: Regner, Wilesco; Japanese: Saito; and maybe others) who use brass boilers and they are perfectly safe AND legal.
I understand if one argues that copper has certain advantages over brass in certain applications, but dismissing brass completely as a boiler material is an unnecessary exaggeration.

Brass boilers can usually be made lighter than most copper boilers, which is important if you want to build a small model boat. That's why I like Saito boilers, for instance: they are very light for their size.
Besides, they even mix brass and copper, using copper for parts like fire tubes, which are subjected to the highest temperatures, and brass for less stressed parts.

If one designs a boiler well and uses it within it's specified pressure range, with adequate safety valves, the probability of something going wrong is remote.

[bogstandard]

Kno3,

I gather you are from the Continent, where it seems that the safety of others is taken with little regard.

If you got your metallurgy correct, you would soon find that brass is a totally unsuitable material for boilers OR their fittings. Unless of course you go for the expensive non-dezincing brass. I which case, it would be cheaper going for copper any way.

Here in the UK, the home of the Industrial Revolution, we came to the conclusion that copper was the ideal material for small boiler making well over a century ago. It is such a shame that the rest of the Continent, and other worldwide countries are taking such a long time to catch up. Being a hundred years behind in model boiler technology must be very frustrating for you.

there are several steam engine makers (German: Regner, Wilesco; Japanese: Saito; and maybe others) who use brass boilers

If these people went into making nuclear reactors, would you let them put one at the bottom of your garden. Just because they have a household name doesn't mean it is correct. They are in it for making money, and if brass boilers can be made cheaper, that is the way they will go.

brass and copper, using copper for parts like fire tubes

That is even worse than an all brass boiler. Not only do you have the de-zincing problems, you now introduce electrolytic action as well. Who the hell thinks up the marketing ideas for that lot.

'Roll up, roll up, come and buy the only steam powered self leaking battery in the world. When steaming, just stick a wire to each end of the boiler and get free lighting for your model. After a while, your boiler will turn into a nice hot water fountain, with little plumes coming from every orifice. Only 150 Euros Extra'

the probability of something going wrong is remote.

Probability is not a word you remember when you have a facefull of brass.


John 

[kno3]

Kno3,

I gather you are from the Continent, where it seems that the safety of others is taken with little regard.

If you got your metallurgy correct, you would soon find that brass is a totally unsuitable material for boilers OR their fittings. Unless of course you go for the expensive non-dezincing brass. I which case, it would be cheaper going for copper any way.

Here in the UK, the home of the Industrial Revolution, we came to the conclusion that copper was the ideal material for small boiler making well over a century ago. It is such a shame that the rest of the Continent, and other worldwide countries are taking such a long time to catch up. Being a hundred years behind in model boiler technology must be very frustrating for you.

there are several steam engine makers (German: Regner, Wilesco; Japanese: Saito; and maybe others) who use brass boilers

If these people went into making nuclear reactors, would you let them put one at the bottom of your garden. Just because they have a household name doesn't mean it is correct. They are in it for making money, and if brass boilers can be made cheaper, that is the way they will go.

brass and copper, using copper for parts like fire tubes

That is even worse than an all brass boiler. Not only do you have the de-zincing problems, you now introduce electrolytic action as well. Who the hell thinks up the marketing ideas for that lot.

'Roll up, roll up, come and buy the only steam powered self leaking battery in the world. When steaming, just stick a wire to each end of the boiler and get free lighting for your model. After a while, your boiler will turn into a nice hot water fountain, with little plumes coming from every orifice. Only 150 Euros Extra'

the probability of something going wrong is remote.

Probability is not a word you remember when you have a facefull of brass.


John 

I don't know if you're trying to be funny when you say that the safety of others is not a concern in Europe, but I can assure you that in an over-regulated country such as Germany, it really is. I am not going to engage in a game of "who was first and who is better" and I agree that brass can have problems if it's not handled the right way.
However, the brass model boilers made by the companies mentioned earlier undergo strict testing and are made according to the specific EU and national safety regulations, which I have no reason to doubt. They function well and I have never heard of one exploding and injuring people.
Remember, we are talking about model boilers, using low pressures, not full-size ones. Nobody says you are not right pointing out the advantages of copper over brass, but please allow room for other people's opinion too. If brass boilers were as hazardous as you portray them to be, they would have long banned them.

By the way, model steam engines are a source of great fun, not frustrating at all and I hope we can keep the tone of this conversation friendly and civil.

[bogstandard]

I was being deadly serious, but trying to keep it light hearted.

I was a first hand user of a supposedly safe brass boiler from Wilesco. If I came across another one being used, I would stay well away.

Remember, we are talking about model boilers, using low pressures

That is honestly the sort of reply I expected.

I gather you started off on your crusade with the 'toy' engine brigade as well, who seem to have no understanding of safety at all, because they think their boilers are just low pressure vessels, and as such think they are immune from injury.

Low or high pressures mean nothing, it is a pressure vessel, and as such has to be treated that way.

You can make your boilers from whatever you want, be it chocolate or titanium, but you should NEVER advocate the use of any suspect material to any other member, here or anywhere else.

You are leaving yourself wide open to litigation if the person you gave the go ahead to has any sort of accident.

Hence my reply to Withnail, where I told him not to use brass.

You came along and have now told him, in your eyes, brass is perfectly safe as a boiler material.

So whoever reads this post now, now has your say so that brass is safe.

If I was you, you should be praying no one has an accident because of your recommendation to use brass as a boiler material.

That is all theoretical, but could easily turn into reality.

Now that is serious.

John

[kno3]

I don't know what bad experiences you had with brass boilers, perhaps you'd like to tell me. Until then, I don't see why I should consider brass boilers unsafe.

Why don't you write a letter to your local authority competent for pressure vessel safety and ask them to ban brass steam boilers? If your arguments and evidence are correct, I'm sure they will listen.

[bogstandard]

Until then, I don't see why I should consider brass boilers unsafe

'I' is the most appropriate comment you have made yet. You are willing to go down the route of brass boilers, I would suggest you don't send people down your route until you have a lot more experience under your belt.
 
Rebuilding a couple of other peoples products, doesn't give you the insight or knowledge to recommend anything to anyone. Anything can be made to look pretty, but it doesn't mean it is safe.

I have no need to do anything at all, and certainly won't do, to satisfy someone like yourself. We have enough knowledge and legislation in our boiler restrictions and insurance legislation to cover our boiler builds, and if those are followed, you will end up with a perfectly safe boiler.

I would suggest you come back in a few years when you have gained experience in building engines and boilers yourself, and share your new found wisdom with us. Until then, I would suggest you sit quietly in the background, and learn something useful, rather than contradicting known issues, of which it seems you know little or nothing about.

A little knowledge is sometimes more dangerous than no knowledge at all.

Just to qualify my statements, I have built many dozens of boilers to my own and other peoples designs, and hundreds of steam engines, and have never had a single safety issue with any of them. Unfortunately I don't have the facilities to make boilers any more, but if I did, I would confidently make safe boilers again.

How many have you made?

Come on, don't be shy.

[kno3]

Until then, I don't see why I should consider brass boilers unsafe

'I' is the most appropriate comment you have made yet. You are willing to go down the route of brass boilers, I would suggest you don't send people down your route until you have a lot more experience under your belt.
 
Rebuilding a couple of other peoples products, doesn't give you the insight or knowledge to recommend anything to anyone. Anything can be made to look pretty, but it doesn't mean it is safe.

I have no need to do anything at all, and certainly won't do, to satisfy someone like yourself. We have enough knowledge and legislation in our boiler restrictions and insurance legislation to cover our boiler builds, and if those are followed, you will end up with a perfectly safe boiler.

I would suggest you come back in a few years when you have gained experience in building engines and boilers yourself, and share your new found wisdom with us. Until then, I would suggest you sit quietly in the background, and learn something useful, rather than contradicting known issues, of which it seems you know little or nothing about.

A little knowledge is sometimes more dangerous than no knowledge at all.

Just to qualify my statements, I have built many dozens of boilers to my own and other peoples designs, and hundreds of steam engines, and have never had a single safety issue with any of them. Unfortunately I don't have the facilities to make boilers any more, but if I did, I would confidently make safe boilers again.

How many have you made?

Come on, don't be shy.

I you don't want to satisfy my curiosity, then please allow me to have an opinion, even if you don't agree with it.
Until you are going to prove your statements, I have no reason to take your opinion on boilers for a fact. Aggressive blanket-statements and an arrogant attitude are not the right way to convince me. However, I don't want you to believe that I'm only trying to contradict you no matter what: I am willing to change my opinion if you can provide evidence. I have nothing to loose, and could even learn something new in the process.

To answer your question: I haven't made any boilers, but I am running enough of them, both brass and copper, to know that they are safe if used within the designed parameters. They are made by respected companies who design them according to current regulations and I haven't had any safety problems with them, nor did I hear of safety issues from anyone else: in other words, no brass boiler exploded or otherwise malfunctioned in a way that would be hazardous.

By the way, brass boilers are legally being sold even in your country...

[Stuart Badger]

Let me just put in my two-pennorth here!

I think Kno3 that you are maybe not completely sure of the regulations. There are NO tests or regulations for boilers/pressure vessels OF ANY KIND that are below 1.5 bar-litres.

Bar-litres

This is the water/steam volume of the boiler (in litres) multiplied by the working pressure in bars (1 bar = 14.5 psi). This must be stated on the Test Certificate.

Boilers below 1.5 bar-litres do not need to be tested . We will normally test up to 500 bar-litres and, exceptionally, up to 1100 bar-litres.

So small toy boilers working at low pressure are considered safe even if made of brass BUT this assumes that the boiler is HARD (silver) soldered, and is NOT heated by gas. Brass is a hard and relatively non-ductile material unsuited for a TRUE pressure vessel. I think you will find that ALL of the brass boilers sold are well below 1.5 Bar-Litres and are heated with solid fuel tablets or methylated spirits. I HAVE HAD A WILESCO BOILER EXPLODE and an old Mamod boiler split whilst under a relatively low pressure (the safety vlave had NOT lifted as both boilers were not up to full pressure (thankfully).

Frequency of Examination

The hydraulic test is required every four years for copper boilers, one year for steel boilers.

You will notice that the statement above taken from the CURRENT EU LAWS on pressure vessels does not mention Brass boilers - this is because under the regulations for pressure vessels ABOVE 1.5 Bar-Litres BRASS IS A BANNED MATERIAL and is considered totally unsuitable and dangerous for pressure vessel construction.

Please do not assume that because you don't know differently - that you are right. The advice offered here is for yours, and others safety. By all means use brass for a very small, low pressure boiler (if you must) but you must take care to stay WELL within the limits. In any case copper is an easier to work and safer material. And please remember what I have stated here IS FACT - NOT opinion. You can search the internet in your country and download the regulations.

Stuart Badger

[derekwarner_decoy]

Hi PD's & thanks Stuart for the clarification....Derek

The pressure vessel (boiler) supplied has been manufactured in accordance with the legislation; PRESSURE EQUIPMENT REGULATIONS 1999 SI No 1999/2001 (“PER”) P.E.D. 97/23/EC".

This subject [boiler strength & alternate materials] is not new....the forum history will confirm we discussed utra thin stainless steel shelled boilers with a compentent member some time back......... ......

[Eddy Matthews]

Also remember that brass is an alloy of copper and zinc, and it's a known fact that steam will slowly leech the zinc out of the brass, causing loss of structural integrity and in extreme cases the metal can even become porous!

I'm afraid those are statements of fact, determined by much cleverer people than me! So I'm certainly not going to argue about them....

Regards
Eddy

[derekwarner_decoy]

OK PD's .....just try this one  ...Sandy form ACS told us about this years ago...... .............Derek

http://books.google.com.au/books?id=lazmQb9aG6kC&pg=PA295&lpg=PA295&dq=steam+leaching+zinc+from+brass&source=bl&ots=BW8-5t2eIg&sig=WJTWwKwZAqqTnxqvQpUaTOi3oGQ&hl=en&ei=8JTDSZP2HYmMsAPxs-HlBg&sa=X&oi=book_result&resnum=3&ct=result

PS....K&S metals do not offer a chemical or metallurgical comment in their product range....but I think their brass will outlast me by many years