Regarding Weld area calculation for branch reinforcement as per ASME B 31.3

[ATUL KHATRI]

Hello experts,
As per clause 304.3.3 of ASME B 31.3 (Reinforcement of welded branch connections), Area A4 is the area of other metal provided by welds and properly attached reinforcement.

While calculating the weld area , the minimum value of tc=0.7 Tb or 6mm (1/4 in.) ,except that larger dimensions may be used if the welder has been specifically instructed to make the welds to those dimensions.

Now my query is --
1.In case if welder has gone with higher weld thickness and weld throat is coming more than 6mm, than the weld area for reinforcement should be calculated based on higher thickness or restricted to 6mm only ?

2. Does the extra heat input due to additional weld may distort the base metal and also affect the mechanical properties of weld ,HAZ and base metal ?

Best Regards

 

[XL83NL]

1. I dont see no reason to use the as welded area for reinforcement, however, since the design should be completed in the engineering phase, I dont see how this would benefit you.
2. Yes. But it depends; e.g. on the material, welding process, welding position, joint design, etc., etc.

 

[ATUL KHATRI]

Thanks XL83NL
Response to your responses
1.I had doubt on using additional welds as reinforcement since codes (ASME VIII or ASME B 31.3)only mentions the minimum weld thickness and does not clearly says that additional weld should be considered as reinforcement.
I do agree that these things would be finalized during design but here in particular case , vendor had purchased the plate of lesser thickness (25mm instead of 26mm as required) ,did the additional fillet weld above full penetration weld between branch and main pipe (here branch and main both pipe had same thickness )and now justifying the additional weld as reinforcement.

2.Here the material is P11 , GMAW. Should the final hardness of Weld ,HAZ and base metal be enough to check the weld properties ?