slip on flanges 1

[ianmontes]

Dear Sirs,

What type of welds on slip - on flanges, socket weld or fillet weld?
What is the difference?

Need your advise.

Thank you

 

[pennpiper]

ianmontes, Look here:
Images for Socket Welds:

https://www.google.com/search?q=soc...X&ved=0ahUKEwj_k-vC0tnKAhUKlB4KHWCAB1QQsAQIGw

Images for Fillet Welds:

https://www.google.com/#q=Images+for+Fillet+welds

Sometimes its possible to do all the right things and still get bad results

 

[pennpiper]

There is also this:

http://www.eng-tips.com/viewthread.cfm?qid=295603

Sometimes its possible to do all the right things and still get bad results

 

[XL83NL]

Actually, there's no such thing as a socket weld, it's a fillet weld laid down on a socket joint.

 

[gtaw]

As already mentioned, the pipe fittings mentioned all utilize a fillet weld to join the fitting to the pipe. The size of the weld is dependent on the welding standard, i.e., welding code, used. It is typically a function of the wall thickness of the pipe.

If you are using ASME, be sure to check whether the weld size specified by the code is the weld throat dimension or the weld leg dimension. Most of the ASME pressure piping codes specify the minimum throat dimension of the fillet weld joint the pipe to the hub of the fitting. One must multiply the throat dimension by 1.414 to get the equivalent fillet leg dimension. It is the leg dimension the welder wants to know and it is the leg dimension that is specified by the welding symbol if one is using AWS A2.4 standard symbols for welding, brazing, and NDE.

NAVSEA uses MIL-STD-22D as their standard weld joint details. It includes details for slip-on flanges, socket joints, etc. While conservative, they work and have performed well for, well let's say a heck of a long time. The fillet welds used in piping per NAVSEA employ an unequal leg dimension. The longer fillet leg is positioned against the pipe while the shorter leg equal to the thickness of the pipe wall is placed against the hub of the fitting. One of my friends did a study on the unequal leg fillet weld and their performance compared to an equal leg fillet weld. The results of the study was that where fatigue is concerned, the unequal fillet weld out performed the equal leg fillet by a wide margin.

Best regards - Al