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Post by runner42 on Feb 21, 2021 5:01:56 GMT
The BI OK'd the barrel but advised that silver solder joints should have a good fillet on both sides. Better spending time at this stage than later, but my opinion is that excessive silver solder will run away on subsequent heat ups if gravity is working against you. Also he said to scallop the steam dome because if it is not done then the steaming space is reduced. At first I didn't understand the relevance of this but apparently if not scalloped the water is sucked up into the steaming space, so to prevent this water levels have to be reduced. He added that he was guilty of not doing it on his last locomotive.
Brian
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Post by runner42 on Feb 22, 2021 2:54:06 GMT
I have attached the drawing of the regulator bits that are associated with the sealing of the regulator rod as it exits the backhead. I am unsure of the sequence of assembly, the regulator flange and gland are obvious but the neck ring and any sealing material to be used are not so obvious. Can anyone clarify the sequence of assembly and indicate how sealing is achieved. Is it gland packing material or an O ring? Brian  regulator bits by Brian Leach, on Flickr |
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Post by coniston on Feb 22, 2021 11:30:33 GMT
Not 100% sure without seeing the whole assembly with regulator rod, but my assumption would be the flange is silver soldered into the boiler (I'm sure you know this). After the regulator rod is passed through then the neck ring is slipped onto the rod followed by the gland with a few wraps of graphite gland packing in between. There will be studs on the flange for the gland to slip over with nuts to tighten the gland. The gland should only be tightened just enough to compress the packing to create a seal, not too tight. No11 is clearance for 3/16 so I assume the regulator rod is 3/16", is there something on the regulator rod that needs the 1/4" hole in the flange for clearance? or maybe DY just preferred to have a 'floating' neck ring for the packing to compress against?
Hopefully someone who has a B5 can confirm more for you.
Chris D
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mbrown
Elder Statesman
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Post by mbrown on Feb 22, 2021 12:29:21 GMT
I think DY proposed a collar on the regulator rod so that, once the neck ring and gland had been assembled, the rod was held longitudinally. In other words, the collar is 1/4" dia and passes through the bush on the boiler, and the neck ring and gland seal the regulator rod and prevent it coming out. At any rate, that's how I have done it on two locos, copying DY's instructions as I understood them, and it works fine.
Malcolm
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Post by runner42 on Feb 22, 2021 22:23:23 GMT
Thanks Chris and Malcolm. Yes there is a 1/4" collar on the 3/16" dia regulator rod, the 1/4" dia hole in the regulator flange allows this collar to pass through and the neck ring then prevents this from moving longitudinally back. I assume there is packing of some sort between the neck ring and gland and this is held in slight compression by the gland.
I should have studied the regulator rod drawing and it would have been obvious for the reason for the neck ring, but it was on another sheet (that's my excuse).
Brian
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Post by runner42 on Feb 26, 2021 6:27:57 GMT
A small milestone, but a significant one none-the-less. The boiler barrel with the outer wrapper, somokebox tubeplate and backhead screwed together just so I can stick it in the chassis and verify that the major measurements are OK. Everything appears OK, except that the 24 3/4" measurement is short by 1/4". This was caused by the backhead flanges being only sufficient to meet the AMBSC Code Part 1 requirements, however DY's boiler drawing shows the backhead flanges to be wider but not specified by measurement or indicated by drawing note. This wider flange enable the backhead to sit further out from the outer wrapper.  boiler in locomotive by Brian Leach, on Flickr This shortfall in flange depth also caused the manifold connection to the boiler to sit at the junction of the backhead and outer wrapper, shown in the photograph instead of on the top curve of the backhead. Pitfalls for the unwary. This is no big deal as far as I am concerned.  boiler in locomotive1 by Brian Leach, on Flickr I shall have to re-think the position of the top feed assembly, initially wanting it to be close to the steam dome like the Black 5 locomotives I saw. However DY positioned it close to the smokebox because its size is such that it overpowers the steam dome. I'll wait and see.  boiler in locomotive2 by Brian Leach, on Flickr Brian |
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mbrown
Elder Statesman
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Post by mbrown on Feb 26, 2021 8:59:32 GMT
The position of the top feed varied on Black 5s - some had a top feed combined with what appeared to be a small dome (in reality there was no dome). Later ones had a dome and top feed just in front of it, and later still (under Ivatt) the boilers had the top feed mounted a lot further forward.
So you have some choices!
Malcolm
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choochooenthusiast
Involved Member
Building a 3D printed Crab 13065. A wagon (or a few) in the works.
Posts: 70
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Post by choochooenthusiast on Feb 27, 2021 2:19:43 GMT
So you have some choices! Indeed, just limits the amount of numbers to choose from. |
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Post by runner42 on Mar 8, 2021 6:54:07 GMT
On the smokebox tubeplate, DY requires that the blower tube threaded end be screwed directly into the smokebox tubeplate, using a 5/16" x 40 tpi thread. However, the AMBSC Code Part 1 requires that all threaded connections to the boiler be made with a threaded bush. The threaded bush is T shaped and when affixed to the boiler will protrude by the thickness of the top part of the T. The code requires that for a 5/16" dia the thickness shall be 3mm. If I attempt this there is going to be an interference issue with the wet header and the blower union. In the photo you can see the blower union both in the machining drawing and in the red circled area on the smokebox tubeplate. The latter is turned 90 deg so the threaded connection taking the connection to the blast nozzle is pointing away. My question is there any way in which this interference can be overcome? My only thoughts are to reverse the bush so that the 3mm section is inside the smokebox tubeplate. Brian  blower tube issue by Brian Leach, on Flickr |
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peteh
Statesman
Still making mistakes!
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Post by peteh on Mar 8, 2021 7:06:50 GMT
On the smokebox tubeplate, DY requires that the blower tube threaded end be screwed directly into the smokebox tubeplate, using a 5/16" x 40 tpi thread. However, the AMBSC Code Part 1 requires that all threaded connections to the boiler be made with a threaded bush. The threaded bush is T shaped and when affixed to the boiler will protrude by the thickness of the top part of the T. The code requires that for a 5/16" dia the thickness shall be 3mm. If I attempt this there is going to be an interference issue with the wet header and the blower union. In the photo you can see the blower union both in the machining drawing and in the red circled area on the smokebox tubeplate. The latter is turned 90 deg so the threaded connection taking the connection to the blast nozzle is pointing away. My question is there any way in which this interference can be overcome? My only thoughts are to reverse the bush so that the 3mm section is inside the smokebox tubeplate. Brian Need to run this one by your boiler inspector but as the union flange is greater than 3mm (5/32) then could you use the union instead of a bush, still silver soldered onto the tubeplate. You will of course have to see how that works for the connection at the other end of the union. |
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Post by runner42 on Mar 8, 2021 7:17:52 GMT
On the smokebox tubeplate, DY requires that the blower tube threaded end be screwed directly into the smokebox tubeplate, using a 5/16" x 40 tpi thread. However, the AMBSC Code Part 1 requires that all threaded connections to the boiler be made with a threaded bush. The threaded bush is T shaped and when affixed to the boiler will protrude by the thickness of the top part of the T. The code requires that for a 5/16" dia the thickness shall be 3mm. If I attempt this there is going to be an interference issue with the wet header and the blower union. In the photo you can see the blower union both in the machining drawing and in the red circled area on the smokebox tubeplate. The latter is turned 90 deg so the threaded connection taking the connection to the blast nozzle is pointing away. My question is there any way in which this interference can be overcome? My only thoughts are to reverse the bush so that the 3mm section is inside the smokebox tubeplate. Brian Need to run this one by your boiler inspector but as the union flange is greater than 3mm (5/32) then could you use the union instead of a bush, still silver soldered onto the tubeplate. You will of course have to see how that works for the connection at the other end of the union. Thanks Pete, but the blower union cannot be permanently connected to the smokebox tubeplate. As you see from the blower union drawing that there is a 3/16" x 40 tpi thread that is used to screw the union into the blower pipe that in assembly is first screwed into a collector union silver soldered to the backhead. With the blower pipe just protruding past the smokebox tubeplate the blower union is then screwed both the pipe and smokebox tubeplate. Brian |
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Post by John Baguley on Mar 8, 2021 12:17:40 GMT
Hi Brian,
If you are not allowed to put the flange of the bush inside the boiler could you move the wet header assembly forwards by 3mm to regain the clearance i.e. make the steam pipe flange 3mm thicker or make the wet header 3mm longer ?
John
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Post by runner42 on Mar 8, 2021 22:26:22 GMT
Hi Brian,
If you are not allowed to put the flange of the bush inside the boiler could you move the wet header assembly forwards by 3mm to regain the clearance i.e. make the steam pipe flange 3mm thicker or make the wet header 3mm longer ?
John
Hi John, it is an idea, but unfortunately I have already made the parts so it will require some rework. If I proceed as you recommend I will have to make adjustments to the superheater. I will see if the BI would entertain reversing the flange first. The code doesn't specifically indicate that reversing the flange is not allowed as you would expect, so it will be up to the BI to make the judgement. Brian |
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Post by coniston on Mar 8, 2021 22:54:11 GMT
Or maybe if you have made the wet header you could add a 3mm spacer between it and the boiler bush?
Chris D
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Post by runner42 on Mar 9, 2021 6:21:59 GMT
Or maybe if you have made the wet header you could add a 3mm spacer between it and the boiler bush? Chris D Chris I have done a bit of a compromise. I have reduced the blower bush thickness to 3/32" (2.38mm), this is a deviation from the AMBSC Code Part 1, but I was forced to take this action, because the spacer I produced to bring the wet header out further could only be 3/32" thick because a greater thickness would not allow sufficient penetration of the regulator bush into the smokebox tubeplate. I couldn't reverse the blower bush because in the reversed position the threaded section would extend beyond the smokebox tubeplate so nothing was gained. Have to see if it passes the pub test. This is an Aussie saying used often to indicate an evaluation, it isn't suggesting that I ply the BI with beer to get the right result LOL. Brian  blower wet header by Brian Leach, on Flickr  blower wet header1 by Brian Leach, on Flickr PS The BI generally conducts a visual inspection at first and if it looks right then it is right, so there is little chance that a thickness measurement would be done. |
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Gary L
Elder Statesman
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Post by Gary L on Mar 9, 2021 12:11:35 GMT
Hi Brian, If you are not allowed to put the flange of the bush inside the boiler could you move the wet header assembly forwards by 3mm to regain the clearance i.e. make the steam pipe flange 3mm thicker or make the wet header 3mm longer ?
John
I’m trying to think of a good reason for not putting the flange inside the boiler, and I can’t. It is actually mechanically stronger that way. I imagine the habit of putting the flanges outside is a matter of convenience in construction more than anything. But ICBW. Gary |
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Post by coniston on Mar 9, 2021 21:39:06 GMT
Or maybe if you have made the wet header you could add a 3mm spacer between it and the boiler bush? Chris D Chris I have done a bit of a compromise. I have reduced the blower bush thickness to 3/32" (2.38mm), this is a deviation from the AMBSC Code Part 1, but I was forced to take this action, because the spacer I produced to bring the wet header out further could only be 3/32" thick because a greater thickness would not allow sufficient penetration of the regulator bush into the smokebox tubeplate. I couldn't reverse the blower bush because in the reversed position the threaded section would extend beyond the smokebox tubeplate so nothing was gained. Have to see if it passes the pub test. This is an Aussie saying used often to indicate an evaluation, it isn't suggesting that I ply the BI with beer to get the right result LOL. Brian blower wet header by Brian Leach, on Flickr blower wet header1 by Brian Leach, on Flickr PS The BI generally conducts a visual inspection at first and if it looks right then it is right, so there is little chance that a thickness measurement would be done. Hopefully your solution will be accepted, yes even I can understand your 'pub test' great phrase which may now be used over here  I was thinking that you may be able to leave the bush silver soldered into the boiler as designed but place a spacer between the bush and the we header, that would not affect the boiler design and it would only mean another gasketed joint or us an O ring seal? Hope your work gets approved so you don't have to make anything again, Chris |
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Post by coniston on Mar 9, 2021 21:42:42 GMT
Hi Brian, If you are not allowed to put the flange of the bush inside the boiler could you move the wet header assembly forwards by 3mm to regain the clearance i.e. make the steam pipe flange 3mm thicker or make the wet header 3mm longer ?
John
I’m trying to think of a good reason for not putting the flange inside the boiler, and I can’t. It is actually mechanically stronger that way. I imagine the habit of putting the flanges outside is a matter of convenience in construction more than anything. But ICBW. Gary Hi Gary, you are right that the strength is actually improved but most bushes also form a face for sealing so the increased area provided by the flange is beneficial, particularly where gaskets or seal washers are used. You could of course make the bush bigger so the small end diameter coming through the plate is big enough for a face seal but then all the bushes would need to be made of larger more expensive material, so I guess that is the most likely reason for the outside flange design being continued? Chris D |
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Mar 9, 2021 23:49:09 GMT
I’m trying to think of a good reason for not putting the flange inside the boiler, and I can’t. It is actually mechanically stronger that way. I imagine the habit of putting the flanges outside is a matter of convenience in construction more than anything. But ICBW. Gary Hi Gary, you are right that the strength is actually improved but most bushes also form a face for sealing so the increased area provided by the flange is beneficial, particularly where gaskets or seal washers are used. You could of course make the bush bigger so the small end diameter coming through the plate is big enough for a face seal but then all the bushes would need to be made of larger more expensive material, so I guess that is the most likely reason for the outside flange design being continued? Chris D Yes Chris, very true. Probably academic now that the job’s done, but the extra cost of bushing material wouldn’t be an issue for a one-off. And I can’t see it catching on as a general practice because all the bushes would have to be fitted before the boiler was assembled. (I presume they aren’t- I’ve never built a boiler and don’t plan to!) But as you say, it is stronger (i n extremis) so I don’t see any grounds why a BI could object to it. Gary |
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Post by britannia on Mar 12, 2021 16:22:38 GMT
I have attached the drawing of the regulator bits that are associated with the sealing of the regulator rod as it exits the backhead. I am unsure of the sequence of assembly, the regulator flange and gland are obvious but the neck ring and any sealing material to be used are not so obvious. Can anyone clarify the sequence of assembly and indicate how sealing is achieved. Is it gland packing material or an O ring? Brian regulator bits by Brian Leach, on Flickr |
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