Welding of O-lets

Date 07-01-2008 13:23

You might do a search on the forum. There have been some good threads on this already. The bottom line being in most instances the amount of weld metal on O-lets is way overkill.

By Pipeslayer (**)

Date 07-01-2008 14:27 Edited 07-01-2008 14:29

Have run into this many times. I've done pipeline work B31.3 and 31.4 where they do not fill them up. In B31.1 they do. I know that on small bore stainless it will warp severly witout a strongback and even then the pipe is doglegged. The thing that comes up is that after a few passes you 've achieved wall thickness, remember that an O-let is a reinforced outlet, therefore requiring more weld than wall thickness. However I'm not the authority on this.

By Ashbandy Date 06-26-2015 08:22

Interpretation: 2.10
2·10, 2·11, 2.12
B3 1.3 In~rpretations ~o. :2
SUbject: 327.4.4; Welded Branch Connections
\ '
Date Issued:
File:
May 25, 1983
1639 --
Question: Figure 127.4.8(F) of ANSI/ASME B31.1 shows a "Typical Partial Penetration Weld
Branch Connection for 2 in. NPS and Smaller Fitting," and 127.4.8(C) allows its use by taking exception
to the requirement for full penetration groove welds. Paragraph 321.4.4(c) of ANSIIASME B 31.3 does
not contain this exception. However, 327.4.4(a) states, "No attempt has been made to show all acceptable
types of construction ..." Does 327.4.4(a) allow partial penetration types of branch construction?
Reply: No. Only full penetration groove weld types of branch construction are allowed. The
Committee will consider Fig. 127.4.8(F) of ANSI/ASME B31.1 for inclusion in ANSI/ASME B31.3.

By Mr Maui Wowi Date 07-09-2008 09:22

its all a matter of opinion (the man in charge's opinion that is). but if they prefer to fill it all i generally tie in good with the first weld or so then just fill with the rest to avoid blowin' through. "what they don't know won't hurt 'em"

By 803056

Date 07-09-2008 15:25

That's a scary response if I ever read one.

It is usually what isn't known that kills people. It is usually decisions made by individuals not qualified by education or experience that hurt us the most often.

I had a project a couple of weeks ago. An engineer asked me to assist him to inspect an amusement ride. An original shop weld had failed and was repaired by someone that was unknown to the current owner. Let's step back and fill in a few blanks before continuing the story. This amusement ride was a "repossession" that was purchased by the current owner. The inspection is mandated by state statue, i.e., the ride has to be examined by a licensed engineer. That's where I got into the act.

A main structural weld had failed at some point and it was repaired. The term "repaired" is being used loosely at this point. The weld was "butt ugly". The weld was a wide weave that contained slag inclusions that extended from one side of the weld to the other, porosity, and undercut. Someone attempted to repair the welds with "high viscosity" paint to fill the voids, slag, and undercut, some of which was nearly 1/8 inch deep.

I rejected the repairs which immediately sent the owner over the edge. "You can't reject that weld, it's not broken! This ride is built like a battleship. It will never break and if it did, what's the worst that can happen? A kid will feel a big bump at the worst!"

My reply was that although it was built like a battleship, it clearly failed at some point and it needed to repaired by a welder that knows how to weld.

The engineer agreed that he would not approve the repair of the ride unless the repair welds were removed and rewelded by someone that was qualified to do so.

As you can imagine, as the welds were excavated the picture changed somewhat, because other welds that were supposed to be CJP were not and they had to be repaired as well. The owner was jumping up and down at that point because he can't use the ride at an event on the 4th of July and we're costing big money!

Just another example of someone (the owner) trying making decisions they were not qualified to make. In this case endangering the well being of untold numbers of children.

How many people could be affected by one of your welds should it fail? Are you qualified by education, training, and experience to make decisions about how much weld is required to prevent a weld from failing in service? Do you know for sure the owner will not change the operating conditions sometime in the future? Consider for one moment that the owner most likely assumes you welded the fitting and other components in the system per the appropriate code and per the contract drawings.

As I said in my opening statement, "a scary response if I ever read one" and a good reason to have well qualified welders and inspectors on every project.

Best regards - Al

By jrw159

Date 07-09-2008 15:44

APPLAUSE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

By Pipeslayer (**)

Date 07-09-2008 17:55

To me your experience with that job was awful. You did the right thing. As for the owner,his behavior borders on criminal. People that operate weld shops and business'es with unqualified people should be fined heavily and or put out of business!!!! They are a disgrace to our craft and they profit from it by exploiting people (crack heads and etc.) I wish we had a State body that monitored these small steel companies and weld shops. I'd take great pleasure in putting these folks out of business. The bad welds you spoke of was probably a crack head working for $12 per hr while some fat cat sits back at $55 per hr endangering lives.

By 803056

Date 07-09-2008 20:15

I gave you a synopsis of what transpired. The owner of the amusement ride had two "certified" welders look at the welds after I rejected them. Both said the welds would hold up to anything that they would be subjected to and that was without removing the paint to reveal the slag inclusions, etc.

I asked the first welder how he intended to fix the welds. He said he would lay a couple of weld beads over the welds that were already there, because they weren't broken. I asked what machine he expected to use. He pointed to the Miller "CP-200" collecting dust in the corner with a tank of CO2 attached. I asked what gas he intended to use. He said the CO2 would work just fine. I told him if he was a certified welder, I would eat my hat, sweaty sun visor and all. I didn't get any reply to that.

The second "certified" welder backed out after I told him all the existing "repair" welds would have to be removed before depositing any new weld. He didn't like the idea of having to grind out all the existing weld because he didn't have an air carbon arc cutting outfit.

The third welder that finally took on the job whined and cried the entire time because he didn't know if he'd ever get paid, didn't want to carbon arc gouge and weld in the overhead, didn't want to work on the gravel, etc. One of his remarks was well founded. I didn't get paid and it is questionable if the welder ever got paid. I was never called back because as the welder whined to the owner; "every time the inspector shows up he keeps finding more stuff to fix."

The truth of the matter is everything that had to be repaired was in my initial inspection report.

The engineer never got called back to finalize his inspection either. It wouldn't surprise me to hear that another engineer was hired to rubber stamped what was done. After all, I can't fault him, he would have no idea of what the original condition of the amusement ride was.

The original engineer said that is was highly unlikely we'd see our money. I told him I would rather kiss a check good bye, but know the ride isn't going to hurt someone because of something I let slide. He agreed that it was better to be able to sleep at night and know we didn't let an unsafe ride get back into service, than wonder if it would break and hurt someone's child.

This was the second amusement ride this year that this has happened. The next time you take your kids or grand kids to a carnival, look the ride over to see that it is safe.

For your viewing pleasure, the attached photo is one of the CJP groove welds I rejected. The magnetic particle test was performed (with paint intact at the contact points) to obtain a better photo of the weld's condition.

Attachment: CJP-Not.jpg (40k)

By dbigkahunna (****)

Date 07-10-2008 03:02 Edited 07-11-2008 00:05

ASME B31.3 328.5.4(d) gives the size of the finish filets. However these are the Minimum, but can be larger. The finish filet can be the minimum thickness of the carrier or header pipe.
Figures 328.5.2A shows the filet weld size.
BABRT's

By 357max

Date 07-10-2008 04:15

Make certain there is expansion at the bottom of the o let. about 1/16". Don't bottom out the pipe on the o let.

Attachment: ES-49BranchConnections.pdf - PFI ES-49 Standard (guidance) Best explanation I've ever studied on weld -o - lets (86k)

By jon20013 (*****)

Date 06-27-2015 02:26 Edited 06-27-2015 05:23

Sorry, not sure why that PFI ES-49 Standard uploaded into 357max post but it was me who uploaded it. :confused:

Attachment: ES-49BranchConnections.pdf (86k)

By 803056

Date 06-28-2015 01:23

Key words: integrally reinforced branch fitting.

Al

By jon20013 (*****)

Date 06-28-2015 06:51

If folks read Chapter 8 in that ES-49 attachment I believe (well, at least in my experience) procurement maybe a root cause for O-lets which might have too large of weld area... unless the user does burst testing to prove differently then they "must" weld to the prescribed weld area, including fillet "reinforcement."

By 803056

Date 06-28-2015 13:42 Edited 06-28-2015 22:01

Manufacturers are required to subject their designs to rigorous testing to demonstrate the design performs as expected. The integrally reinforced branch fitting (IRBF) is used so contractor does not have to add reinforcement around the branch fitting to compensate for the base metal removed from the run pipe.

If the contractor neglects to weld the IRBF as prescribed, all bets are off and the IRBF no longer meets the code requirements.

If the designer determines the IRBF welding requirements are excessive, there are ways around the requirements, i.e., simply design the connections as a "stab-in" using a pipe coupling or pipe nipple. Just make sure the necessary reinforcement is added if the calculations indicate the reinforcement is required.

In any case, it isn't the welder's prerogative to make the determination whether the IRBF is to be partially welded or completely welded as per the manufacturer's requirements. It is doubtful an individual that calls these fitting by their brand name knows where the design requirements are found in the code. If the welder has the necessary education, he can design the system as he sees fit, but my experience indicates few welders have the where-with-all to do the necessary calculations and fewer yet have the engineering degree and professional registration needed to make those decisions. The comment isn't intended to be a put down of any welder, it simply an observation.

Any inspector that accepts a IRBF welded differently than as prescribed by the manufacturer is negligent in the performance of his/her duties unless the necessary calculations to support the decision to weld the IRBF differently than prescribed by the manufacturer are completed and the welding requirements are detailed on the drawings. Just my opinion you understand.

Best regards - Al

By jon20013 (*****)

Date 06-28-2015 20:18

Excellent response, as usual Al. :cool: