Yarrow boiler

[NilochParticipant @niloch]

The construction of this boiler commences in ME 4366 and in alternate issues to 4389. His specification for the tubes to connect the steam drum to the mud drums is as follows.

 

These are 12mm dia. with a wall thickness of 1mm (S.W.P. about 500psi!) and this size of copper water pipe is freely (!) available from DIY centres etc.

A single 15mm dia. tube is also required for the balance pipe joining the rear of the two mud drums.

 

I am, of course, familiar with 15mm dia. copper water/central heating pipe as well as 8mm dia. for micro-bore and 10mm dia. for mini-bore cedntral heating systems.

 

I have yet to find any 12mm dia. as specified, here in the UK.

 

I can easily source 12mm dia. copper pipe but it has a much thicker wall so that swaging the pipe as described for location purposes might be much more challenging.

 

Mr Holland resides in Spain so 12mm might be common place there. Does anyone know of a source of supply of the 12mm as specified above?

 

Thank you.

 

Edited By Niloch on 13/03/2011 18:37:15

[NilochParticipant @niloch]

Mr Terence Holland’s recent design

[JasonBModerator @jasonb]

1/2″ x 20g tube thats just a tad under 1.0mm may do the job

 

http://www.m-machine-metals.co.uk/

 

So do College

http://www.collegeengineering.co.uk/Materials/coppertube.htm

 

12mm OD is readily available here in coils but I assume you would prefer it in straight lengths

 

Jason

Edited By JasonB on 13/03/2011 18:58:01

[TerrydParticipant @terryd72465]

Hi Niloch,

 

12mm by 1mm wall copper is used in France as a standard plumbing tube it is available in 1m, 2m and 2m lengths. Out of interest the plumbing tubes there are all 1mm thick and increase in size by 2mm so that they telescope. It makes it easy to change diameter without adaptors, but not so handy given the cost of copper now.

 

I am off to my house over there for Easter (and to avoid a certain wedding hype) and if you really need any, and get stuck, I can get straight lengths and arrange to get it to you when i return after Easter. PM me if you need help.

 

Best regards

 

Terry

[NilochParticipant @niloch]

p { margin-bottom: 0.21cm; }

Jason:

Resourceful and helpful as always. Thank you very much indeed but please read on.

Terence Holland sold me the Yarrow seed well over a year ago, despite the fact that this was no ordinary Achillea Millefolium I planted it in a shady cerebral border where it wouldn’t be forgotten. As sometimes happens germination followed some good luck. I was able to secure at never to be repeated prices a steam drum 305mm long x 134.27mm o/d with a 3.19mm wall weighing in at 3.57kg. Similarly, two mud drums were acquired also 305mm long x 66.8mm o/d with a 2.49mm wall weighing in at 1.29kg each. All three solid drawn copper tubes are slightly longer than those specified by Mr Holland and the mud drums are also larger in diameter . I was not over enamoured by those longitudinal strapped, riveted and silver soldered seams resulting from rolled tubes so solid drawn seemed the way to go.

Jason: Holland warns of the danger of melting one of the thin walled tubes that connect the steam drum to the mud drums because of the considerable difference in wall thickness when silver soldering, I am reluctant, therefore, to use anything less than the 1mm specified.

Terry:

So your invitation embossed in gold with the Prince of Wales’ feathers has not landed on your doormat yet! Still, I suppose a new hat for your good lady might set you back the price of a Chiwanese mill!! Allin all, best to go to France for my copper!!

Thank you too very much indeed for your kind offer. I have spent a little time on the LeRoy Merlin web site as well as the Kingfisher (B&Q) owned Castorama site, I found the former more helpful than the latter. Tube de cuivre is listed but I am puzzled by the nomenclature. 8 x 10, 10 x 12, 12 x 14 hard copper tube is listed. Do you think that should be 8 x 1.0, 10 x 1.2, 12 x 1.4 etc? It seems unlikely, because there is also 38 x 40, surely that can’t be 38mm o/d x 4.0mm wall thickness as I’m suggesting by my earlier question. Am I missing something exceedingly obvious? Annealed Copper Crown (coiled) is also listed in a similar way, 5, 15, 25 metre coils etc.

My wife and I have spent far too much time in French bricolage most recently in Avignon where my wife took a fancy to some 1.2 metre long tubular curtain rails which were duly purchased but necessitated a visit to another bricolage for a sizeable roll of bubble wrap and, yes, you guessed it we had to pay excess baggage.

There are 42 boiler tubes in total, 22 at 135mm long and 20 curved tubes at 160mm long. In round figures I would need 7 x 1 metre lengths. However, as I’ve already mentioned my drums are longer by about 30mm so I may be able to squeeze in a few more. I think I would be foolish to buy fewer than 10 x 1 metre lengths. Are you flying or driving? I have some Euros left from a recent outing to Basilicata!

If you can help further with the previously mentioned nomenclature issues, I would be most grateful. Perhaps we should spare others any further postings on this ‘plant’ and correspond through pm.

[JasonBModerator @jasonb]

8 x 10, 10 x 12, 12 x 14

 

8mm bore x 10mm OD, 10mm bore x 12mm OD, 12mm bore x 14mm OD

 

The suppliers I listed also do 18swg which is a little over 1mm so a bit less likely to melt.

 

J

Edited By JasonB on 14/03/2011 20:22:03

[NilochParticipant @niloch]

I knew that !!!!!!!!!!!!!!!!!

Very many thanks, yet again, Jason.

Terry: it makes common sense to buy from a British supplier in case of problems.

 

 

Edited By Niloch on 14/03/2011 20:32:27

[JasonBModerator @jasonb]

Just another thought, as most of the tubes are bent anyway whats the point in buying the harder straight tube, the coiled stuff will be easier to bend.

 

Though I’m not sure if these plumbing coppers contain more lead which you don’t want for boiler work.

 

Jason

[NilochParticipant @niloch]

About half are straight Jason. There must be a British Standard somewhere that applies to plumbing copper and as you say lead content would not be welcome. I daresay m-machine-metals and CES would have specifications for the copper that they supply.

Thank you.

[TerrydParticipant @terryd72465]

Hi Niloch.

 

I was going to confirm internal x external diameter as the basis for dimensions of cu tube en Francais but Jason got there first.  I’m not sure about lead in plumbing grade copper. surely it could leach out in hard water.  I thought that problem was the reason for the use of non lead bearing solder? perhaps we will go the way of the Roman empire!

 

The Norme Francais conforms at least to EU standards as does BS I believe. I do think that the copper tube is pure cu but Jason may know better. I drive over in my 3.5 tonne van so that I may bring back more liquid refreshment. If you would like a few metres let me know.  As it is a few weeks before I go perhaps you could check on the specification of the stuff (copper tube that is).

 

The envelope did drop on the mat but the allure of French cheese, wine, venison and good company is lust too great.

 

Best regards

 

Terry

 

 

Edited By Terryd on 14/03/2011 21:45:59

[NilochParticipant @niloch]

Posted by Terryd on 14/03/2011 21:41:33:

…………………..is lust too great.

You naughty boy!!

[TerrydParticipant @terryd72465]

Hi Niloch,

 

As far as I can find from research, plumbing copper tubing is made from very high purity copper and is solid drawn. I did not think that lead would be allowed in plumbing quality tubing. Apparently even when using scrap copper, reverberatory techniques are used to remove tin and zinc from the melt to refine the copper to 99.9% purity.

 

Hi Jason,

 

I thought that you would have known that given your building qualifications?

 

Regards

 

Terry

Edited By Terryd on 14/03/2011 21:55:31

[TerrydParticipant @terryd72465]

Posted by Niloch on 14/03/2011 21:52:19:

Posted by Terryd on 14/03/2011 21:41:33:

…………………..is lust too great.

You naughty boy!!

Another Freudian typo perhaps

 

Terry

[Ian S CParticipant @iansc]

he main thing with domestic copper tube is that it is low arsenic, Arsnic being a major contaminant of copper, this tends to up the price a bit, but with copper the price it is, the percentage is getting less. Ian S C

[JasonBModerator @jasonb]

Terry I’m not sure if its all plumbing copper or just certain ones (maybe the softer coils?) The last couple of paragraphs on this page of CuP Alloys has a few notes on copper spec for boilers though some applies more to oxy as the heat source.

 

http://www.cupalloys.co.uk/brazing-of-copper-c99.html

 

J

[TerrydParticipant @terryd72465]

Hi Jason,

 

I don’t know where Cupalloys get their data from. As you know lead is soluble in soft water and is poisonous. As the their page says, the lead is not dissolved in the copper but is in the form of discrete particles which could dissolve where there is soft water.

 

That is the reason why lead based solders are now not allowed in plumbing systems. There should be no lead in copper pipes used for potable water systems. You quotation says that lead is added to improve machinabilty, I don’t know of any need to machine copper tube used in plumbing?

 

The Relevant British standards state:

 

“Copper Tubes to BS (British Standard) 2871 – Dimensions and Working Pressures

The copper used in the manufacture of tubes is phosphorus deoxidized copper Cu-DHP defined by British Standard BS. 6017: 1981. This also corresponds to the ISO denomination Cu-DHP.

The minimum copper content is 99.85% and the residual phosphorus content is between 0.013 and 0.050%. This deoxidized copper is not affected by reducing atmospheres and consequently is well suited to welding and brazing. The density of copper is 8.9 g/cm³. its melting point is 1083 ^oC and its coefficient of linear expansion is 16.8 x 10^-6 per ^oC (ranging 20 ^oC – 100 ^oC)”

 

If there were lead in the material the ISO denomination would include the letters ‘Pb’ to designate lead in the alloy.

 

Further, the max safe working pressure under the standards for 10 x 12 would be around 7N/mm which equates to just over 1000 psi.

 

Hope this helps,

 

Terry

Edited By Terryd on 15/03/2011 09:36:44

[NilochParticipant @niloch]

Towards the end of his construction serial Holland writes about feed-pumps, specifically:

The Tinker pump is quite easy to build compared with the direct-acting donkey pump concept. Castings are available for this pump and I find that it is operationally more reliable than the direct acting types………..

I have been unable to find the Tinker castings listed neither on the Reeves 2000 nor on the Blackgates sites. Any suggestions please?

[Ian S CParticipant @iansc]

Terry you mentioned that maching would proberbly not be needed, my data sheet for copper (8 different alloys) rates PD copper as 20 compared to free maching brass at 100, so no its not the best. One thing that is not listed as an alloy or impurity is Lead  Ian S C

Edited By Ian S C on 15/03/2011 12:23:00

[JasonBModerator @jasonb]

Tinker pump

[NilochParticipant @niloch]

I knew you’d know! Thank you.

[NilochParticipant @niloch]

Tinker – a slide crank boiler feed pump. A six part series by J.P.Bertinat starting in ME for 05/01/1996. Would anyone be able to help with the words and music please?

[Rod AshtonParticipant @rodashton53132]

Recently acquired the " innards" of a Yarrow boiler. Looking for inspiration on the cladding, chimney and insulation.

Have been shown an ME article Vol 157 page 40 and another continuation page (which I do not have the reference.) This describes things very well. Sadly the means to obtain a copy are not available. Would anyone help please? Or the ME 4366 and in alternate issues to 4389 as mentioned above if at all possible.

[Ady1Participant @ady1]

I've plonked most of the 3780 and 3782 articles into my album

only taken me 1 and a half hours so far to upload it… I'm rapidly losing interest in the internet nowadays…

[Rod AshtonParticipant @rodashton53132]

Ady – Many thanks. Most appreciated.

[Author]

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