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londonrain
10-20-2007, 11:08 AM
Call on leaking 1 1/2" back-flow on inlet MA...After further review we suggested the entire assembly be reworked. Cracked MA and compression fittings on both ends= reworked.


http://webpages.charter.net/nixdiecast/bf1.jpg
1 1/2" compression fitting...
http://webpages.charter.net/nixdiecast/bf2.jpg
replaced the compression fitting on the galvanized 1-1/2" with a 1-1/2" union...
http://webpages.charter.net/nixdiecast/bf3.jpg
from the top view you can see how misaligned the inlet side was and caused the MA to crack at the treads...
http://webpages.charter.net/nixdiecast/bf4.jpg

Wet_Boots
10-20-2007, 11:49 AM
Just curious, couldn't the original compression fitting still work on a stub of sch 40 pipe? (if the elimination of a dissimilar-metals connection was worth pursuing, and said compression fitting a good one)

londonrain
10-20-2007, 12:06 PM
Just curious, couldn't the original compression fitting still work on a stub of sch 40 pipe? (if the elimination of a dissimilar-metals connection was worth pursuing, and said compression fitting a good one)Since the BF was misaligned and the only way I could see to straighten the inlet side was with four 90's. Then the compression fitting, IMO, would be subject to less lateral support thus the pipe would more than likely come out of the compression fitting under the 100+psi's. Not a big fan of compression fittings on a main line unless there is no way the pipe can move at all..Last thing I wanted was get it all back connected and watch the pipe come out of the compression fitting or a few day later have a 90 with a crack because of movement....been there done that....:hammerhead:

Wet_Boots
10-20-2007, 12:45 PM
I became a fan of 'waterworks' compression fittings when the utility pressure-tested my POC (Ford pack joint) connection, and I suddenly realized I'd forgotten to tighten the outer pipe-clamp screw. Still held fine at about 100 psi.

(I'd have still opted for a sch 80 union, or even brass - what the hey, it's only {customer} money :))

londonrain
10-20-2007, 12:53 PM
(I'd have still opted for a sch 80 union, or even brass - what the hey, it's only {customer} money :))
I went against a sch80 union because if it leaked at the 20 year old galvanized 1 1/2" pipe, I figured I could crank down on a galvanized union greater than a plastic union and have a failure because of a crack. Had a hard time even finding a galvanized union let alone a brass(which was my original plan)....

Dirty Water
10-20-2007, 01:01 PM
A 1 1/2 brass union would run you about 15-20 bucks. they are not cheap.

looks good, i would had just used a coupler instead of a union and used the glue 90's as my last glue point.

Wet_Boots
10-20-2007, 01:08 PM
{......if it leaked at the 20 year old galvanized 1 1/2" pipe}

Maybe if I adjusted the gamma on some of these pictures, I'd see things like the galvanized main. (and aren't they a bunch of fun to play with) - galvanized is certainly the way to go, and as for previous comments....

http://tbn0.google.com/images?q=tbn:lmx96pMXVzMsoM:http://images.usatoday.com/life/_photos/2005/02/18/inside-snl-radner.jpg
"Never Mind"

londonrain
10-20-2007, 01:11 PM
A 1 1/2 brass union would run you about 15-20 bucks. they are not cheap.

looks good, i would had just used a coupler instead of a union and used the glue 90's as my last glue point.
The only place I was worried about a drip was at the 1 1/2" old galvanized pipe which only had about 2 1/2 good threads left. I was worried about a drip at this point, if I used a coupling and had a drip then complete rework for 1 drip. With a union if I had a drip then I would loosen union, crank on end and re tighten union.

londonrain
10-20-2007, 02:54 PM
A tip : If you have a threaded PVC fitting break off inside a metal fitting (IE: backflow preventer) , the easiest way of getting it out is with a torch. Heat the broken fitting and pry it out with a screw driver......WARNING - Watch out for the fumes...

BrandonV
10-20-2007, 04:01 PM
fire good, me like

Wet_Boots
10-20-2007, 04:50 PM
A tip : If you have a threaded PVC fitting break off inside a metal fitting (IE: backflow preventer) , the easiest way of getting it out is with a torch. Heat the broken fitting and pry it out with a screw driver......WARNING - Watch out for the fumes...It's all about the fumes - you can even do the torch trick for a broken nipple in a plastic spray head, but the margin for error is slim

Mike Leary
10-20-2007, 05:36 PM
A 1 1/2 brass union would run you about 15-20 bucks. they are not cheap.
looks good, i would had just used a coupler instead of a union and used the glue 90's as my last glue point.

The plumbers (for once), taught me a neat trick about brass unions....
in the shop, take the biggest wrenches you have & tighten the hell out of
them...it "blends" the flanges..never had one leak after that.

Dirty Water
10-20-2007, 05:51 PM
The plumbers (for once), taught me a neat trick about brass unions....
in the shop, take the biggest wrenches you have & tighten the hell out of
them...it "blends" the flanges..never had one leak after that.

lol.

you have to have them perfectly clean or you'll never get a seal. thats the biggest trick.

as far as using a torch to remove broken pvc....ever heard of a nipple extractor/

Mike Leary
10-20-2007, 05:53 PM
as far as using a torch to remove broken pvc....ever heard of a nipple extractor/

I don't think nipple extractors got much farther than Portland.

londonrain
10-20-2007, 06:50 PM
lol.

you have to have them perfectly clean or you'll never get a seal. thats the biggest trick.

as far as using a torch to remove broken pvc....ever heard of a nipple extractor/I have a few nipple extractors and they work great on 3/4" and 1/2" barbs but not so great on 1" and larger MA....on many occasions the nipple extractor will not grab the pvc or just spin ......:clapping:

Mike Leary
10-20-2007, 07:11 PM
I have a few nipple extractors and they work great on 3/4" and 1/2" barbs but not so great on 1" and larger MA....on many occasions the nipple extractor will not grab the pvc or just spin ......:clapping:

Nipple extractors should be replaced every season 'cause they lose the sharp
edge needed....:from actual experience::

londonrain
10-20-2007, 07:32 PM
Nipple extractors should be replaced every season 'cause they lose the sharp
edge needed....:from actual experience::
That's why I use a torch on anything 1" and up plus I only use the torch on broken PVC inside metal......easier and cheaper...:drinkup:

Mike Leary
10-20-2007, 07:40 PM
That's why I use a torch on anything 1" and up plus I only use the torch on broken PVC inside metal......easier and cheaper...:drinkup:

And we are carefull burning m.p.t. adapters out of ball valves when melting
could occur?:nono::drinkup:

FIMCO-MEISTER
10-20-2007, 07:55 PM
Nipple extractors should be replaced every season 'cause they lose the sharp
edge needed....:from actual experience::

Not a problem for us. We lose 2-3/year:dizzy: i do torch heat in desperation. Try to avoid if I can. Had to resort to something I've criticized on this site but it saved my tush yesterday. Tying in some pots that the pool people had run 1/2" copper into we couldn't reach a couple with the torch because they didn't run them out far enough under some steps. Got some copper glue and it worked like a champ. The stuff really impressed me. Runs 22.00 for a small elmers glue bottle size.