NR305........

By JA

Date 09-08-2007 12:25

were welding these heavy moment connections with E70T-6 "NR305"........the flange thickness is 1" and about 12" wide,,,,,,, the root pass and the next 5 or 6 passes are fine , but as we start to bring it up to the top , as the weld thickness starts to lessen and is reduced , transverse cracks are starting to show up......?
were not running things too hot , and the wire is new , (presumably dry),,,,,,,,,what could be causing this......????????

By JA

Date 09-08-2007 12:34

one other thing , base metal is A992...........

By jwright650 (*****)

Date 09-08-2007 13:31

What diameter wire are you using? What parameters are you using? 5/64" does run pretty hot, so you may not be as hot as you think for that dia, if you are using 5/64" Usually the guys tell me it is "too hot" only because they don't use heavy enough gloves for that amperage, it isn't too hot, just too hot for their hands.

Need some more info....

By jwright650 (*****)

Date 09-08-2007 13:42

Here is the data sheet on that wire.

Attachment: NR305.pdf (51k)

By JA

Date 09-09-2007 01:32

were running 3/32" dia wire,,,,,,,,aprox 27 volts,,,,,,,,450 amps,,,,,,,,,,,,theres no reason this should be happening,,,,,,it only starts around the last 1/4" of fill in the 1" thick single bevel groove , all the way to the cap , especially in the cap.........transverse cracks , some carry all the way through , some just about an 1/8" , from the toe toward the center.....?????????
whats going on here....?

By JA

Date 09-12-2007 11:41

i guess i'll call lincoln.............