taking mains apart

ChrisJ

I need to take this apart so I can build my new 3" drop header and am curious what everyone thinks will be the easiest route.  I am assuming trying to get the two unions apart will be my best bet?  Should I soak anything in WD40 or other penetrating lube?



Problem is, even if I get the union on the right apart I still need that nipple out of the 90 elbow so I can install my king valve.

lchmb

Heat

I like to warm them up with my torch, give them a little tap and then try and remove them...

ChrisJ

Cutting

What do you think the chances are of me actually getting these pipes apart?  As far as heating them goes, will a MAPP torch be enough or will I need more?

Paul Fredricks_3

.

I usually attack these pipes with a sawzall. I'd cut them just under the upper elbows, leaving about 1/4" of nipple sticking out. Once the pipes are out of the way I stick the sawzall blade into the fitting and cut flat and perpendicular against the remainder of the nipple inside the pipe, being careful to keep the blade as flat against the pipe as possible and trying not to cut so deep that I damage the threads. I make 2 cuts, about 1/2" apart, take a punch and knock out the chip, then bang the rest of the nipple in on itself to loosen it, then spin it out.



I have always found this easier than trying to spin everything out, only to resort to this method anyway. If there is any damage on the threads, wicking, teflon and dope usually take care of any leak potential. Hopefully you can follow what I'm talking about.

lchmb

heat

I use my mapp gas and heat around the fitting. Dont go to fast and allow the heat to work into the fittings (you dont need to blast them cherry red just get them toasty warm). I use 24" pipe wrench's and keep cheater bars on hand in case but have only had a couple over the years I couldnt get apart...Good luck either way you go.

Of course, be careful with the torch, dont burn anything..

Hap_Hazzard

I'm with lchmb

Heat the fittings with a MAPP torch. Keep a spray bottle of water on hand and quench the pipe before you start to wrench it. (It also comes in handy if you set anything on fire.)



Don't bother trying to use WD40 or CRC or Liquid Wrench. It just makes a bad smell when you put the torch to it. Those joints have pipe joint compound in them, and that won't let anything into the threads.



One problem I've run into is that the pipe can get deformed by the wrench jaws in such a way that it makes the wrench slip around, and it doesn't grip until you've run out of room to keep turning. If you can find them, a couple of angled pipe wrenches in different sizes can come in really handy, as they grab at different angles.



Beating on the fittings can help or hurt, depending on whether the fittings are cast or malleable. Malleable means able to be deformed by hammering, so if you hit it hard enough, you can make it out-of-round, and out-of-round pipes don't turn too well in out-of-round fittings. If it's cast, you might manage to crack it with a hard, well-placed hammer blow, but sometimes breaking the fittings is the only way these things come apart.



When I use the heat it and beat it approach, I use an air hammer, because it lets me control how hard I'm hitting it, and it can deliver a hell of a lot more blows in a minute than I can. I try to rattle all the way around the joint so it doesn't distort the fitting too much. I'm still not convinced that it really does any good, but it helps to get my frustrations out.

ChrisJ

cast

While emptying the dehumidifier this morning I took a look at the elbows and noticed they have a seam.  I have to assume this means they are cast iron?

I'll be draining the boiler over the next few nights and then I'm going to start tearing the boiler down.   For some reason taking the old one apart seems like a lot less fun then putting the new one together.  All well.

Hap_Hazzard

Seams aren't a good indication

MI fittings, as I understand it, are just CI fittings that have been heat-treated to make them less brittle. Maybe some of the pros here know of a better way to tell them apart, but I've always gone by whether you can leave a mark if you whack it on the edge with a hammer or if it shows wrench marks.

crash2009

Whack em,

I watched the guy take mine apart.  I am just guessing that my elbows were cast iron.  Pat whacked the elbows with a hammer.  He sometimes had to whack them a few times.  I beleive he was aiming for a certain spot, that once hit, would cause the elbow to explode.  My guess is he was aiming for the seam.  Get a good pair of foam sealed safety glasses before you try to bust em.  When they explode they fly everywhere, you might want to tarp your self in to minimise the cleanup.



We had to use the existing boiler so we had to be gentle with the fittings close to the boiler.  The nipples coming out of the boiler were sprayed generously with PB-Blaster, several times during the day.  Twenty four hours later, the nipples just backed right out.  If the nipples had not co-operated at that point, we were prepared to use the torch. 

ChrisJ

header removed

It took a bit of effort and I realize I only busted the unions apart which is probably a lot easier than elbows will be, but its a start.



Well now its definately official.  I have to get the new boiler installed before it gets cold out.

moneypitfeeder

glad to see

That you've made progress. We are in the middle of doing the same thing. (installing a header where there wasn't one etc). The only thing I can recommend is a second body to help you out. I had to come upstairs and admit defeat to my husband when I inadvertently moved the boiler by trying to turn the riser out of it,  and ask that he come down and back me up. That and for every break I have to make, I beat on the fitting with a framing hammer, not hard enough to break a fitting but enough to loosen rust, heat with a torch, and then break with the biggest wrench and breaker bar I can find. Good Luck with your wrenching!!

Long Beach Ed

Beware

Where we can, we break the elbows with a big lump hammer.  Beat them two ro three times with all you've got and they do explode off the pipe. 



Of course that can break other stuff, so generally we try not to use too much force or shake things up too much.   We've made lots of extra work for ourselves by letting a helper use the hammer.



With the proper tools you cut the piping with a Sawzall and thread it in place using a Ridgid 700 threader.  This way there's minimal stress on the pipe and you get your cut exactly where you want it.  



The post about cutting through the threads into the fitting is right on too.  That works, though it's usually hard to angle you saw up there and you don't want to hack up the threads too bad.