doubt on how to make this joint

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Hi guys, i need some help here, we arr making a 12" 45 degrees pipe bifurcation, as you can see on the attached picture, but im not sure about the joint on the 45 degree pipe, im showing a drawing with two options for the joint, could you tell me wich one is the correct one, or if both of them are wrong, the would you tell me how it must be done? Whats the name of this kind of fabrication? I cant find any good information about those joints, and is there any norm regulating this type of joint?? Thanks very much!! Attached Images
Reply:NevermindSearch pipe coping.  I'd say the left drawing looks correct.Last edited by Teggy1; 11-30-2015 at 10:54 PM.
Reply:Its called pipe coping, saddle tie in. Your fabrication process should include a certified welding procedure, designed by engineer, that details all the information you are looking for. Ex...bevel degree, set gap, fillet specs, etc....Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:Instead of asking the forum do what Wagin suggested.  The customer / architect or designer of this fabrication should be answering this question for you.  If for some reason there is a failure in the system or your weld you'd be far better off having the documented proof of why you did it one way versus another because if push comes to shove the customer, architect or designer will be pointing the finger at you and your insurance carrier.Lincoln Weldanpower A/C 225 D/C 210 /6kw auxiliary (code 9113 & 9108)Lincoln Weld Pak 100 MigMiller Maxstar 150 TigLincoln Scratch Tig 200 ampMiller 8-VS Suitcase Flux CoreHypertherm Powermax 30Victor Torches / Regulators
Reply:Ok thanks guys, i'll ask for that information. I got blueprints with no welding specs at all. Thanks!!
Reply:Check a copy of the pipefitters blue book, or other similar reference guides. http://www.amazon.com/The-Pipe-Fitte.../dp/0970832125There are at least two options for how to fit up this type of branch connection.  Both of the illustrations you provided(welds shown in red) are a type of partial joint penetration weld(PJP).  In my experience these types of branch connections are usually complete joint penetration welds(CJP).  CJP welds would require beveling both sides of the joint in a manner very different from what' shown in your illustrations.The engineer that designed the piping should(must) know which type of weld is appropriate for the component you're fabricating.  What you show might be appropriate; but only the designer of the piping system can tell you for sure.  IF a CJP weld is required, the book I referenced above will provide some guideance on the joint beveling and fitup.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:The one on the left is totally wrong. The one on the right would be correct if the branch pipe was bevelled with the ID tying in where the welds are located.Sometimes they want the hole bevelled, too - with both ID's tying in together. This is way more involved.I'd be pretty hot if somebody tacked that whole piece together like that for me to weld.Last edited by TimmyTIG; 12-01-2015 at 11:44 AM.
Reply:Id be pissed too if that spool was all tacked like that.  If your prints don't have weld procedures, they're trying to put the liability back on you.  I wouldn't waste another minute on that thing till I got answers.