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Coldman
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Had to turn a 1/2" x 90 degree butt weld ammonia stop valve into an in-line screwed valve. Here are the parts given:
V1.jpg
V1.jpg (72.87 KiB) Viewed 790 times
Ist step prep all vees and root weld toe nipple to elbow:
v2.jpg
v2.jpg (135.37 KiB) Viewed 790 times
Step 2, cut elbow in half, prep vees and tack onto valve body:
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V4.jpg
V4.jpg (109.66 KiB) Viewed 790 times
Then fully weld out with two passes:
root pass 80amps x 3/32" ER70S-4
Cap 70amps x 1/16" ER70S-2
V7.jpg
V7.jpg (69.31 KiB) Viewed 790 times
Clean up inside, assemble valve and pressure test
V5.jpg
V5.jpg (102.04 KiB) Viewed 790 times
Job done.
Flat out like a lizard drinkin'
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First I've seen a 90° elbow used to make a straight in line fitting...great job!
Richard
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That's one I've never seen. Well done!
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Poland308
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I had forgotten how much of a pain small pipe was till I did some 1/8 npt half couplings today. Went quick and fine but I know I'm out of practice. Nice work on the valve.
I have more questions than answers

Josh
Rudy Ray
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That was clever using the 2 45's to make that valve into a straight run. I like it.
Coldman
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Thanks fellas.

@Josh
We definitely don't do the spaghetti stuff often enough. Things happen real quick.
Gotta keep up with rapidly changing torch angle
easy to overheat
easy to over penetrate and fill up the pipe
easy to over re-enforce cap
Secret is to go fast and manage all the above.

I'll be getting more practice in the next couple of weeks. Job coming up to chop out and replace rusty 1/2" and 3/4" pipes. I'll try and sneak in some pics - no photos site.
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Nice work - you done good, Coldie!
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Clever and nicely done :)
Dave J.

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noddybrian
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Excellent work as always & kudos for managing small pipe in short bit's that well - I know how bad it sucks - but is it just me that thinks it was a retarded job in the first place ? I get Apollo 13 - times like that you give people a pile of what bits you have to hand & lock them in a room till someone figures it out - but this ? did someone buy the last straight valve on earth ? is the lead time on production 6months ? - are they like 6figures ? -it's presumably a paying job not something your building with bit's in your shed so how was it not cheaper to get the correct orientation valve rather than the number of hours it must have took to do ? or do they pay you that little an hour ? ( I hope not - your a skilled craftsman )
Coldman
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Screwed gauge valves for ammonia in 1/4" and 3/8" are common but after that they get rare and mostly not stocked as industry standard is mostly welded or flanged. In-line valves are also avoided in flow lines because the fluid changes direction three times so pressure drop is much higher than one right angle valve. In this case another refrigeration contractor needed the inline screwed valve in hurry, had the parts on his shelf and was prepared to pay me to do it. Small stuff is not my favourite work it can be hard to set up you can't use clamps and the other problems already mentioned. I actually enjoyed this little job for the set up problem solving and I didn't have any rework.


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noddybrian
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Thanks for the info - I never worked fridge stuff so it made no sense - I like the fact you're going to try to take pics on a no photo site ! I did the same years back on Channel Tunnel project - got a few of CF's they really did'nt want shared ! - all on 35mm though.
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