Boiler Sectioning

[GWRdriver]

I've spent some time the last few days hacksawing a Maid of Kent boiler in half and I thought it might be of passing interest. The reason for the sectioning is that this is one of the worst boiler jobs I've ever seen and I'm doing the world a favor by putting this hound out of commission. Without going into detail this is a textbook for how NOT to do it. Dispite its appearance I seriously doubt it has been steamed and if it had it would not have held pressure (which is perhaps a very good thing.)

So as not to have this completely go to waste, sections of the platework will be retrieved, flattened, and reformed as the bottom pans and other odd bits in the water tanks for my 2X TICH, now under construction.

[spurley]

Hi GWR

Can you elucidate further on the faults with this boiler please? The picture, on the face of it, looks OK. I know you have said in your post you'd prefer not to go into detail but, unless the 'perpetrator' is likely to sue or worse, I think that it is a very useful part of the learning process to pass on what can go wrong.

I, for one, think it is more than a passing interest.

Cheers

Brian

[GWRdriver]

Brian,
It's not that I'd prefer not to go into detail, it was late last night and I didn't want to take the time to write it out, . . . . and then I wasn't sure that it would be of all that much interest. Legal action by the builder, if his identity was ever known, if he is still among the living, is a non-issue as what I would have to say about the boiler is a demonstrable truth.

I've posted essentially the same message on a US live steam board and someone there has asked me for permission to include it in their club newsletter but that will deserved more detail, at least to the extent that I'm able to provide it, and I proposed to write an expanded report. I'll post that description here when I have it done, in a few days perhaps. It will involve all the usual suspects, lack of bushings, badly done fitting and soldering, etc.

[havoc]

Yes please, more detail about this. If possible with pictures. This because from those pics I can only see 1 (possibly 2) problems and those not really that horrible as you suggest. So please go into more detail when you can.

[abby]

Could you put some close up detail photos of the faults ? and some arrows ( especially if you think the builder is a cowboy )
Abby.

[paul]

abby said:

... ( especially if you think the builder is a cowboy )
Abby.

If so it's probably a Great WESTERN engine. Boom boom!

[GWRdriver]

Abby,
I have no idea who the builder was and it's my guess this boiler has passed through a number of hands, three including my own that I know of, and no doubt more before that, so this cannot be about a person we need worry about now.

The question one might ask me is, if you know so much about boilers how come YOU got stuck with it? The reason I got stuck with it is because it came mounted on a Maid of Kent chassis that was superbly done in every respect, (and with the tender castings) for a price that could justify tossing out the boiler if necessary. It's apparent from the disparity in workmanship that the boiler and chassis were done by different individuals and it's possible the two components were united by a third (or 4th or 5th) unsuspecting or uncaring owner. This we will never know.

[steam4ian]

G'day Harry.
To a novice boiler maker (me) the photos do not make clear obvious deficiencies in workmanship. Some stays appear to be missing but this may simply be due to where the boiler was sectioned and the camera not being able to see into the cavity.
I take it there were shortcomings in the soldering, brazing and seams.

More detail would be most helpful and instructional.

BTW, what did you cut the boiler with?

One good turn deserves another.
Regards.
Ian

[GWRdriver]

Ian,
A 12" hacksaw with an 18t HSS blade. The next couple of days will be very busy for me but I'll respond with more detail in due time.

[Nexuas]

My suggestions for errors...

1. No stays between the front tube plate and the throat plate.
2. A butt joint, rather than a flanged joint on the front throat plate/barrel.
3. No stays above the fire hole door between the fire box back plate and the back head.
4. Central crown stay is considerably shorter than the crown sheet, leaving the front section unsupported.
5. No bushes for the safety valves.
6. no bush for regulator and probably guage glasses.
7. No blow down valve? This is a guess as they maybe on the side of the firebox, or off centre on the front or rear.
8. Dome bush looks a little under engineered in flange thickness.
9. Boiler tubes look a little thin in the wall

Do I win a prize or have I missed somthing?

[stantheman]

Just reading the last entry I wondered what could be seen if the picture was enlarged. I wonder if the fact that it has been cut apart has lost some of the things that appear missing. On closer examination, albeit a bit fuzzy due to the resolution, there is possibly visual evidence of stays in the front plant to throat plate area, heads are just visible at the lower end of the front plate with what could be 'half holes' on the throat plate. The comment about the crown stay made me wonder if the piece lurking in the background is in fact the right hand crown stay and the piece in the foreground is a shorter girder stay, sometimes used in boilers, LBSC's Pansy, for one, I feel had this arrangement originally. Gauge of tubes are again difficult to imagine with the resolution but they do look a bit on the thin side.
Oh and before I sign off, is that a butt strap lurking inside the barrel joint, if it is then this would be a satisfactory joint providing it had been completed in a proper manner.

Just friendly comments you understand, I expect there will be a full and comprehensive account once the writer has the time. Deal or No Deal?

Stan.

[havoc]

Well, I noticed some of these also, but they don't look that important to me.
1: like the previous poster I do see some heads of stays there
2: the butt joint: most boilers are that way these days. Since it is in compression then it isn't a problem if the front of the firebox sits before the barrel
3: likewise I think there are stays (but not as sure about it than point 1)
4: crown stay is a problem. But the biggest one is that there is a plate-stay between the top of the barrel and the firebox. That I consider bad practise. Not enough flexibility.
5,6: bushes depend on the plate thickness. Hard to say but it would be better with them since this plate doesn't look very thick
7: don't know. (Maybe intended to run on distilled water?)
8: might be, but I consider the rules to be as badly overengineered
9: looks like that, but hard to tell on a pic

I would add
10: to sharply flanged at places.
11: too thin crown sheet

[Shawki Shlemon]

"The rules to be as badly over engineered" yes they are but there is a reason for that and that is,this is a hobby and a lot of boilers are built by people who are not boiler makers and therefore there is room for imperfection . I know that the OZ boiler code is over engineered by a great amount but it does give everyone peace of mind and I am happy with that . I am a boiler inspector and see a lot of boilers and if the code was what is needed only ,large percentage of boilers will be rejected and the hobby will not survive .I know there are people there who can build boilers appropriately designed and safe ,but they are the minority.This hobby is for everyone .On the practical side over engineering will make boilers heavier and help in improving traction .That of course is only a side effect may be good or bad !!!

[havoc]

es they are but there is a reason for that and that is,this is a hobby and a lot of boilers are built by people who are not boiler makers and therefore there is room for imperfection .

You are right of course, but it goes straight into my feeling as an engineer.

[chameleonrob]

for the dome, I understand that all material that is removed for the hole must be replaced, I think it should be replaced within 2 1/2 times plate thickness although I can't remember where I heard that, soldering in the tube for the dome actually makes thinks worse according to martin evans, all of which makes sense, it therefor surprised me to see a reputable model engineer in ME to solder in a tube for the dome with only a optional reenforcement plate rather than a proper bush. suddenly over engineering looks very attractive.

btw when GWRdriver posted this picture on another forum he stated that it had been braised (ie brass spelter) and had almost zero joint penetration, look at the bottom of the front tube plate.

rob

[havoc]

for the dome, I understand that all material that is removed for the hole must be replaced, I think it should be replaced within 2 1/2 times plate thickness

According to KN Harris a ring of 125% the plate thickness. That looks sensible to me. But he doesn't say anything about the width.

soldering in the tube for the dome actually makes thinks worse according to martin evans, all of which makes sense,

It doesn't make sense to me. If you have a reference to those reasons I would like to know it. Curious why this should be a problem. Only thin I can think of is corrosion in the inside edge.

regarding the stays: I looked at the rules I have here, and they show if 3 stays on the crown are used then middle should be lower and not touch the top of the barrel.

The quality of the soldering isn't judgable from the pic.

[Shawki Shlemon]

Hi Havoc
I am sorry if I offended you that was not intended , in my reply I also said that there are people who can build a boiler appropriately designed and built safe.You will be included in that minority in a large population of the hobby . My point was in brief it is better to be safe than sorry .The boiler above is a good indication of what sort of workmanship can be employed in building boilers and this is the reason why we have a strict over engineered code . We should happily accept that .

[Lurkio]

Shawki,

Your comments in your previous post about 'over-engineering' make a lot of sense.

Regards,
Lurkio.

[havoc]

You didn't offend me at all Shawki. My fear is that if it becomes so over the top a certain laisser-faire attitude steps in. You know where people don't care anymore "because it is so safe". Once you make things soo thick that you need to take care that the large parts are hot enough and the thin ones not overheated you are making it harder, not safer.

Once you overdo it so much that even non-technical people start to see that it is too much you are asking for trouble.

[Shawki Shlemon]

Hi Havoc
I fully understand what you are saying ,like yourself I am an engineer and a boiler inspector and have built 25 copper boilers .
The adherence to the code by boiler inspectors and keeping the records of all boilers and retesting them periodically will hopefully guarantee safety . So far it has worked fine . I hope that this will continue .