Socket weld question

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Got a job coming up & I have a few questions to throw out to you folks.  Been welding for 20+ yrs and this is the first time I've had to use socket weld fittings.  It's a steam pressure reducing station that will be getting close to 200psi on the high-side.  Just a few pieces are socket welds; couple of 2" and 1 1/2" pieces.  The majority of them are going on the drip legs, all 3/4". All carbon fittings and using SCH-80 pipe.   From what I gather, we should not be butting up the pipe all the way in to the fittings/valves. A 1/16th or 8th of an inch gap sound right?  They've really killed us for time on this thing, so would I be able to crank up the heat on the MIG machine for these, or break out the lil 'buzz box' of a Miller TIG gun?  Seems little different than a slip-on flange without getting a weld on the inside. A quick side rant.... Is it too much to ask of weld fitting manufacturers to put some sort of notch or line to help lining up the flat side of eccentric reducers!?!?!?
Reply:Yes you are suppose to gap the fitting, we always lift about a 1/16. Normally we tig socket weld sometimes stick. I would rather tig then stick.
Reply:how did you manage to weld for 20 years without doing a socket weld?
Reply:1/16th to 1/8th gap, TIG... you'll love them. They are easy to fit and weld, much quicker than a butt weld. Some people like to put a real small first pass in, almost like a "root" to get as much penetration as possible, then fill it up!Lincoln Idealarc Tig 300/300, Lincoln ranger 8, Lincoln LN-25, Miller Sidekick (keeps rockin!), Oxy/Acy torch, Miller XMT-304 with a Miller 60 series wire feeder and high freq. box, Profax positioner 8" chuck, Aaronson 3500# positioner 15" chuck
Reply:what about gap-o-let rings are they helpful with socket weld fittings?
Reply:They do make disposable gap setters that go inside of your fitting and you but the pipe up so you don't have to "measure" your gap. I find that after doing a few socket welds, you no longer have to measure and can do it all with your eyes. I like to look for a spot on the pipe and eyeball an 1/8" gap. You can put the pipe in all the way and mark it with a soapstone, pencil, marker, etc. don't sweat it too much, socket welds are very easy.  And yes, it would be nice to have some kind of point of reference on eccentric reducers to line them up. I find it easier on the larger ones to use a v-head jack stand and rotate it until its closest to the bottom if that makes sense. Just weld it!Lincoln Idealarc Tig 300/300, Lincoln ranger 8, Lincoln LN-25, Miller Sidekick (keeps rockin!), Oxy/Acy torch, Miller XMT-304 with a Miller 60 series wire feeder and high freq. box, Profax positioner 8" chuck, Aaronson 3500# positioner 15" chuck
Reply:Just stick pipe in, mark, and pull pipe out a 1/8''. Best way to square fittings. As far as eccentric reducers go, I use a 2' framing square. Place the inside corner of square on reducer and roll until you get flat. Mark with soapstone.
Reply:Our specs are minimum 1/16" gap. Gap-o-lets are prohibited here, so check your specs before using them.
Reply:Originally Posted by TimmyTIGhow did you manage to weld for 20 years without doing a socket weld?
Reply:Typical practice and required by a number of piping codes is 1/16" gap.  Butt closed, scribe a line, pull back 1/16", let inspector verify, then weld.  Whether or not it actually makes a difference on similar metal welds is another long story!
Reply:Originally Posted by CEPI've been welding way more than double his 20-years, and I've never done a socket weld. Seen lots of them done. When you only work union, and you don't belong to the UA, it may not be very healthy to weld pipe!
Reply:Yes a gap is necessary.  1/16 inch is a usual gap.reason for gap:  If you bottom out the pipe in the socket, when you weld it and then the weld cools and contracts it will further compress the end of the pipe into the socket and will produce stresses  in the pipe, socket, and the weld.  Those added stresses can be high enough to crack the weld (or the pipe or the socket).Put a gap in and don't bottom out the pipe in the socket.Check and double-check for whatever applicable Codes apply to the job.  The best laid schemes ... Gang oft agley ...
Reply:What company doesn"t allow you to use Gap-o-lets? I've worked in Power Plants Fossil and Nuke and that's all we used on socket welds. MoonRise is 100% right, if you don't gap it, it will crack every time.
Reply:I prefer not to use the name of the company I work for, but here is an excerpt from our corporate welding manual..."2.2.3 Socket Weldsa. Fit-up tolerances in socket welds shall be as specified in Attachment C.b. Usage of solid fit-up spacers (gap-o-lets) is prohibited. Water soluble fit-up spacers(Shur-Gaps) may be used when approved by the Station. Shur-Gaps should only beused in systems that do not have filters smaller than 10 mils. The water used toflush the system should be removed to prevent clogging of any components (e.g..filters, instrumentation, etc.)c. Example - Fully insert pipe into socket. Scribe/mark the pipe at the interface of thepipe to socket transition. This scribe/mark will be used as a reference to verify thepull back requirements. Pull the pipe back a minimum of 1/16". Tack bothcomponents."
Reply:I didn't want the company name I was wondering what code your welding to that doesn't allow them, each company has the right to do what they want within the code but i never heard any company not allowing them. It sure makes life easier with them!
Reply:I don't think it's a code issue, but rather some engineer with authority heard about one rusting in two and getting in a piping system, so no gap-o-lets for us! I've never used one, so I don't miss them...
Reply:Originally Posted by TimmyTIGhow did you manage to weld for 20 years without doing a socket weld?
Reply:I know you can't use it in the field but have any of you guys used the "Fitrite" systems? It's like having that third hand you need to fit up and tack! We have 2 sizes in our shop and are getting ready to purchase 3 other sizes.Check out the video on it here:http://www.youtube.com/watch?feature...&v=zj3Si5PeVZI
Reply:I watched the video, I didn't see any pipe fittings. Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:DON'T stare at the white shirt look lower!!!!!!
Reply:Was there something below the white shirt? Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Originally Posted by thegoldoldmanMoonRise is 100% right, if you don't gap it, it will crack every time.
Reply:Originally Posted by SupeOld wive's tale.  In fact, the original paper/research that the 1/16 rule was derived from (based on failures) had photos of the socket welds in question, and they had root pass defects in them...
Reply:It depends on the service temperature. If the product is hot, the socket and pipe need the gap for room to expand.
Reply:Originally Posted by clankerrGot a job coming up & I have a few questions to throw out to you folks.  Been welding for 20+ yrs and this is the first time I've had to use socket weld fittings.  It's a steam pressure reducing station that will be getting close to 200psi on the high-side.  Just a few pieces are socket welds; couple of 2" and 1 1/2" pieces.  The majority of them are going on the drip legs, all 3/4". All carbon fittings and using SCH-80 pipe.   From what I gather, we should not be butting up the pipe all the way in to the fittings/valves. A 1/16th or 8th of an inch gap sound right?  They've really killed us for time on this thing, so would I be able to crank up the heat on the MIG machine for these, or break out the lil 'buzz box' of a Miller TIG gun?  Seems little different than a slip-on flange without getting a weld on the inside. A quick side rant.... Is it too much to ask of weld fitting manufacturers to put some sort of notch or line to help lining up the flat side of eccentric reducers!?!?!?Good catch, rojo! I was so focused on the discussion of the pull-back that I missed that about the MIG. We don't have any GMAW or FCAW procedures for pipe, just GTAW and/or SMAW.
Reply:I just watched the Fit Rite video, and have one question....why is her head smoking?
Reply:Originally Posted by welds4dI just watched the Fit Rite video, and have one question....why is her head smoking?
Reply:Originally Posted by welds4dGood catch, rojo! I was so focused on the discussion of the pull-back that I missed that about the MIG. We don't have any GMAW or FCAW procedures for pipe, just GTAW and/or SMAW.