Wet header / regulator

[russell]

Thought I'd make a start on the boiler bushes while waiting for some drills to arrive.

Came to the bush for the wet header and looking at the drawing it is tapped 5/8 x 26 and the end of the regulator steam pipe is tapped 7/16 x 26. A second bush screws into the bush and at the same time screws onto the steam pipe. This will mean adjusting packing at the other end of the regulator to get the threads to start at the same point. The wet header is then held onto this assembly by screws tapped into the two bushes.

This looks unnecessarily complicated and tricky to assemble. I am thinking of leaving the steam pipe plain at the end, reaming the bush to a sliding fit, slipping a 7/16 O-ring over the pipe and clamping it within a groove machined in the wet header itself.

Is this reasonable or have I missed something?

Russell.

[baggo]

Hi Russell,

Martin Evans did a similar thing for Super Simplex. The O ring sits in a recess in the tube plate bush and is retained by a corresponding spigot on the wet header. I can send you the details if you like.

I came up with the same idea for Helen Longish even though I hadn't seen Martin's method at the time. It works very well and beats fiddling about with screw threads!

John

[russell]

Thanks John,

Doh! Didn't think to look at the Super Simplex articles. I have scans of them all.

The Super Simplex arrangement looks much better but I think the "Hallite" washers are superfluous. I see that he has also reduced the number of screws from seven to four which I'm sure will have more than adequate strength.

Russell.

[baggo]

Hi Russell,

No, I don't see the point of the washers. The O ring will seal perfectly well on it's own.

John

[bonsia500]

Hi Russel,
Way to go. Sounds good to me I have been building this heap of junk on and off for 30 years. often I wish I had not started. Unfortunately I have built it just as it is shown on the drawings. Suprise Suprise this joint starts leaking at about 25 PSI, even though I sealed the thread with some supery duper 260 Deg C thread sealant. So after three unsuccessful steam tests, its ended up buffers down in the waste bin!! Anybody have any clever ideas on how to seal this thread ?

[baggo]

Hi Bonsai500,

I think I would be tempted to machine up a new steam pipe flange with a groove in it to incorporate an O ring to seal against the tube plate bush.

I've not had a lot of luck with some of the gasket goos on boilers but have found PTFE tape to be quite effective. One sealer I have found good is Rocol Pipeseal which is a liquid PTFE but it's very expensive and needs to be left for at least 24 hours before steaming the boiler. A lot of people seem to use Loctite 242 (I think) with good results although I haven't tried it myself. Never had any luck at all with Foliac!

John

[bonsia500]

Hi John,
Thanks for the info, will have to have a look at the super simplex wet end.

Clive

Bonsia500