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Post by Deleted on Dec 15, 2009 22:22:48 GMT
Marco has kindly sent me a progress update on my Brit boiler. I thought you all might like to see what a boiler looks like without flanged plates! I just love the way the whole thing has been simplified.... Neat!
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Post by Shawki Shlemon on Dec 16, 2009 6:46:17 GMT
I haven't seen one like that before , very interesting , good luck .
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steam4ian
Elder Statesman
One good turn deserves another
Posts: 2,069
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Post by steam4ian on Dec 16, 2009 6:54:18 GMT
G'day Shawki.
Does the AMBSC Code allow TIG like that? It looks good.
JB Maybe you can get him to TIG you wayward throat plate.
Regards Ian
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Post by Shawki Shlemon on Dec 16, 2009 7:05:49 GMT
Ian the answer is yes but with conditions , the person is qualified and test piece is required to be submitted to the boiler inspector before welding commence .I haven't got the code here to quote exact words and location but it should be in Joint design and procedures.
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Post by mutley on Dec 16, 2009 10:05:13 GMT
what are the failure modes and pre-warning signs for a copper TIG welded boiler? Speaking as a club boiler inspector and not being fully familiar with the technology and the ins and outs means I personally wouldnt test one.
Andy
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isc
Statesman
Posts: 708
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Post by isc on Dec 16, 2009 10:19:49 GMT
Ludite-isc
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Post by Deleted on Dec 16, 2009 10:45:09 GMT
what are the failure modes and pre-warning signs for a copper TIG welded boiler? Speaking as a club boiler inspector and not being fully familiar with the technology and the ins and outs means I personally wouldnt test one. Andy Andy, nothing personal, but don't you really mean that you wouldn't be allowed to test one under the Regs? This one is being supplied with all test certs and CE marks, and it has been produced by a coded welder working within a professional boiler making Company. I have no worries about meeting the requirements of our Club inspectors! JB
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Post by havoc on Dec 16, 2009 11:20:51 GMT
Very interesting piece of work. It looks like the best of both copper and steel: the conductivity and being able to shape copper and the ease of working of welding. Sadly welded copper boilers are here also VERBOTEN.
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Post by parker3 on Dec 16, 2009 12:05:56 GMT
Being new to the hobby could some one please tell me how any one could be classed as a certified welder when in some cases the person making the boiler may have retired. In the passed I have taken many welding tests, when working and in order to qualify one had to have an inspector watch and record the welding of a test piece after which he would stamp and then send it for a destructive test. If it passed, then they would issue a certificate. This certificate would only cover one type of welding, material, welding position ( flat, vertical, or overhead) and a thickness range. A record of all the welds made under this qualification was then kept (by the employer) and provided they could show that the welder had performed this type of weld, on a regular basis, then a re-test was not required unless there was some change, eg. material grade. From this you will gather that the cost involved runs to hundreds of pounds and far beyond what we can afford for the odd boiler we may make for our hobby. There are other issues which I could go into but for the present I would be interested to read what comments others on this forum think.
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Post by mutley on Dec 16, 2009 12:39:56 GMT
Hi JB, your first hydraulic is covered by the manufacture and so a ticket can be issued for 4 years. When you come to retest in 4 years time and need a 1.5X hydraulic test what failure points should I be looking for with a copper TIG welded boiler? Now if your saying I'm not allowed to test one under the regs how are you going to renew your boiler test cert.? Not trying to be difficult but these are issues that need looking at.
Andy
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Post by Deleted on Dec 16, 2009 14:21:38 GMT
Some controversy already.
ALAN, do you want to move this thread to Boiler Design and Construction? JB
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Post by mutley on Dec 16, 2009 14:45:10 GMT
another thought what are the mounting bushes for the boiler fittings made from?
Andy
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Post by klendo on Dec 16, 2009 15:03:51 GMT
Andy,
Whilst I have some sympathy with boiler inspectors, as at the end of the day should anything go wrong its your backside or potentially your backside on the line as you are the one who signed the ticket..
However Regarding Copper welded boilers or indeed steel welded boilers, this debate has been had in the past surely. As boilers for steam engines were previously riveted flange plates and at some point technology dictated that welding is a quicker and less labour hardy option, whilst still a safe alternative. So what is the difference of failure mode of a copper weld to a steel weld? forgive my ignorance but the failure mode is the same isnt it?
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Post by Deleted on Dec 16, 2009 15:14:04 GMT
another thought what are the mounting bushes for the boiler fittings made from? Andy Andy, the bushes for the Brit are bronze, silver soldered. JB
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Post by mutley on Dec 16, 2009 15:43:42 GMT
Klendo,
Is it? That was the point of my asking the question? TIG welded copper boilers are relativley new to us ME's , they certainly are to me, and whilst I look for modern methods of working and are quite happy to adopt and use new technology, as you rightly say as a boiler inspector my ass is on the line. So what are the failure modes, are they the same as steel what should I be looking for? We have enough trouble with peopel being hesitant about testing steel boilers without adding a subset to copper.
Andy
Andy
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Post by klendo on Dec 16, 2009 16:04:43 GMT
Andy
Thats actually my point..
Why are people hesitant of testing a steel boiler? This has been full sized practice for years and is certainly an area to which I was always brought up on ( Full sized practice I may add )
Generally speaking ( This is my opinion ) a failure mode for a welded steel boiler is that if the weld has not penetrated correctly then you will indeed get a leak at this point and at an extreme case could cause catastrophic failure as this maybe a stress point. the mere fact that the substrate is copper over steel surely is no difference, a filler rod is used of similar composite to make the join. As mentioned in a previous thread if a steel boiler becomes thin it will not explode it will cause a leak, you will only explode a boiler should pressure meet critical mass. The thing that no-one ever mentions are the fittings them selves as these are seldom checked, yet the most lethal part of any boiler should the thread be half stripped or something as pressure behind a fitting is just like firing a gun.
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Post by klendo on Dec 16, 2009 16:10:28 GMT
Andy,
One more addition.
One could always argue the fact of a silver soldered boiler. how do you know that you have a full penetration of silver solder in a said joint just because its a commercial boiler isnt a gaurentee Take model works boilers as an example? you simply pressure test it on a hydraulic and see if she holds pressure. should it pass then all well and good.
The only difference of that of a steel boiler over copper is that steel rusts. This is why in full sized practice we have an NDT test. If full sized insurers will insure a model with a steel boiler should it pass all the criteria why is the southern fed or some of its member so terrified?
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Post by Deleted on Dec 16, 2009 19:22:32 GMT
If you're not suitably impressed by these pictures received this evening then perhaps you should consider giving up Model Engineering! I think it's great that Marco is giving us all the opportunity to view (and possibly criticise) the production process. It just doesn't have the 'Weather Beaten' look that mine had aquired by this stage..... JB
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Post by havoc on Dec 16, 2009 19:27:18 GMT
Because insurers have full-time qualified, permanently up-to-date staff and technology for this. While a ME boiler inspector is a knowledgable amateur. The insurer's tester signs for the insurer, not his person: if the boiler fails in the former case the insurer is the first in line (unless they can proof carelessness), in the latter case the boiler tester is the first in line.
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marco
Active Member
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Post by marco on Dec 16, 2009 19:39:59 GMT
My name is Marco (Steam Technology) and I am the person who is building the boiler for Mr Barret. I can see that there are a lot of enquiries and doubts about TIG Welded boilers. For the welding of the boilers we hold the following certificates. * Welders qualification by BS EN 287 & ASME IX. We are covered to weld copper up to 12 mm thick tube, with no restrictions on positions of welds. * Welding procedures by BS EN 288. Witnessed and certified by an independent body. * All our welding tubes and plates are tested for the following. X ray NDT Vickers & Rockwell HAZ Hardness test. Atomic picture to see any internal structural alterations to the copper as a result of the heat action. In addition we hold the Pressure vessels certificate 97/23 EC valid for the build and pressure test of pressure vessels for submarines (British Navy MOD). This also covers the boilers that we build. All comments and constructive criticism are welcome. I know that this is a different process but we are very careful to keep the old tradition and finishing of the boilers. I wonder what comments I will receive next year when we will be putting on the market Nickel- Duplex and Super Duplex boilers that are already in use in other European countries with the CE stamp. Our intention is to be innovative and to be of help to people in the model engineering world by introducing new techniques so we are not left behind in technology. This country was the forerunner in train technology and if we are sceptical about new processes we run the risk of other countries overtaking us. Any comments or enquiries gratefully received. Marco www.steam-technology.co.uk
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