Crack between flange and elbow

[hmzM]

A weld (ASME IX) between flange and elbow (36", heavy wall) found crack during the RT and has been cut-out and re-weld, but unfortunatelly the second RT result shown that a new crack. Did any clause in the ASME IX or B31.4 or else, mentioned that all cracks shall be cut-out and re-weld? What shall I do, if I don't want to cut-out but I haven't WPS for crack repair?

 

[MJCronin]

ham...

There are requirements in all of the ASME piping codes for at least a visual inspection of welds. Typically, a random percent of the piping welds are either x-rayed or have other UT performed on them.

I assume that this crack would fail the visal inspection.

Review the "Inspection and Fabrication" requirements of the code of record..

My opinions only...


-MJC

 

[GRoberts]

ASME IX doesn't care at all whether the WPS is for welding two pieces of material together, for repair, or what is being repaired (such as cracks, porosity, slag,etc.)
See QW-202.3. The original WPS used to weld the joint is qualified to weld a repair in the same joint. However, just because it is qualified doesn't mean it is advisable. You need to figure out what is causing the cracks, and fix it before you weld again. Why expect a different result with the same process. Also, how did you verify that the first crack was completely removed? Did you cut out the whole joint, or just remove the cracked area, and if so, how are you sure you got the whole crack?

 

[MJCronin]

ham...

In what country is this project ?

-MJC

 

[sk10009]

hamizan

There are recommendations in the ASME code for pressure piping b31.3 and power piping b31.1 "all of the cracks are removed"

 

[chicopee]

It seems to me that you have a CAST elbow that has cracked. Casting are difficult to repair and the only weld that I know to be used successfully is of the bronze type. I personally would replace this elbow and also determine what cause the crack.Perhaps thermal expansion of piping, vibration, heavy loading?