I can't figure out how to mount this with everything that is supposed to be in there and not have it way off the boiler like it is in this pic. The glass is 12" overall 1/2" pipe. And the spacing of the threadboss is 13.5" on centers. I tried to screw the fittings in far enough to get the spacing, but I was afraid I was going to break the body of the gauge they are so tight, it still lacks about 3/8" bringing them in to center spacing. Any ideas on this?
I think it was Ron Fossum who suggested using a gauge glass valves with packing glands, but have the gland seal around a half-nipple coming out of the reflex gauge top and bottom (though I guess you could just do one end that way and thread the other). That way you can infinitely adjust the length of the half-nipple at very little effort or cost. I have not yet mounted my ebay find reflex glass, so I can't say I've tried it yet. I'm guessing you'd want to start with a piece of 1/4" nominal blackpipe and clean up the OD on a lathe to fit the packing.
That would also get rid of the bulky valves and the unions.
If anybody else is looking for reflex gauges, I have found these suppliers on the web, but I have not purchased from them, so I don't know if they're good to work with:
You might want to consider a water column to mount the sight gauge onto, as the picture shows, the sight glass has different centers than the boiler connection.
Another option is to come out of the boiler with 90 degree street elbows, unions and isolation valves in straight runs from the street elbows, then two 90 degree streets into the sight gauge. The bottom union/valve run is horizontal, the top one is sloped upward toward the gauge. Piping should be all 1/2 inch NPT.
I use a 300 psi rated solid bronze reflex glass. After some thought, I eliminated the shut-off valves between the boiler and the reflex gage as not materially making the setup any safer or stronger. This approach may not appeal to you, but it did allow me to mount the heavy gage glass much closer to the boiler.
I think this will work. It will eliminate four fittings on top and bottom. This is machined from 12L14. Should be strong enough. The factory unit pictured is rated for 300 psi steam. They need gaskets still. I'll hydrotest it before usage. The Reflex gauge is rated for 1100 psi at 600 degrees F. The nipples in the boiler to the valves are high strength 5000 psi hydraulic fitting, heavy wall.
I'm so used to being able to blow down my gauge that not having valves makes me nervous. I guess with large diameter passages you will be O.K. I don't think it is likely that you will have any sort of catastrophic glass or piping failure with everything so over built.
And with our little boats we can rock the boat and see if the level changes. I still like a water column and proper valves best. I should talk. I have an unshielded tubular gauge and no water column. A high priority for me is a plastic shield and then later a column and reflex gauge with shutoff valves and blow down valve.
I am told that there are steel hydraulic unions that are better built than the 1/2" plumbing unions I have now. More compact, stronger and rated for high pressure. Does anyone have a link and/or a part number? I have no hydraulic shop here on the island.
Mike
If you think you are too small to make a difference, try sleeping with a mosquito.
Dalai Lama
Custom machining of a special flange, works every time! Nice work.
Just earlier this month is a discussion about blowdown, including gauge blowdown, I assume you have followed that thread. Being able to blow/clean the gauge glass while underway is necessary.
BTW, Mike, I too have a bare circular glass, and also need the plexiglass shield, but to get that fitted, I need to get a roundtuit, anyone know where to get one of these??
Here is the result and I think this will work just fine, still have to hydrotest it.
Plan D involving the old tube glass was to add a piece of clear acrylic tube, 1.5" OD 1/8" wall. Cut it long enough to cover both gland nuts. Then cut a longways slot on the table saw so it could be slid over the pyrex tube and then clamped around the gland nuts with hose clamps or something similar. That would help protect it and direct the steam and water out the backside at least if the glass were to fail. Looks like the reflex gauge is going to work out ok now. I considered omitting the isolation valves and then I looked back over my life.. I decided to keep the valves.
