Can someone Explain Multi-passing?

[d-dawgg]

can some one please explain multi-passing? maby how it is done! thanx

[Blown S-10]

thats when you have/need to make more than one bead down a joint to achieve the proper fill of the joint.

[wrench3047]

I drew a quick thing It has the metal in black, weld pattern in red. It's just a real quick drawing I apoligize because it's rough.

[migmaniac70]

(Each circle of red represents a pass) for those who didn't know.

[lramberson]

Nothing wrong with that SGT.

[Blown S-10]

I drew a quick thing It has the metal in black, weld pattern in red. It's just a real quick drawing I apoligize because it's rough.

that sure is a LOT of pass's

[paulrbrown]

21 is abut the proper number needed for 1" fillet or groove.......Patience is needed!!!!! Paul

[GaryM]

21 is abut the proper number needed for 1" fillet or groove.......Patience is needed!

Wow paul that seems like a lot what rod you doing that with 3/32"???


Gary

[Leons2003]

21 is abut the proper number needed for 1" fillet or groove.......Patience is needed!!!!! Paul

Yeah, and think about NUKE piping, eh Paul
L*S

[hankj]

d-dawg,

Multi-pass technique is required when the thickness of your weldment is greater than your welder's single pass rating. The sequence of beads is important, as well as allowing the weldment to cool between passes, usually to at least 500°.
Beads should be run in sequence - the root pass will be the first bead. Successive beads should be run from one side of the joint to the othet IN SEQUENCE - bead 3 next to bead 2, then bead 4 on top of bead 2, bead 5 next to 4, etc., for as many repetitions as necessary.

Hope that made sense. It would be best if you went to the book store and picked up a copy of "Welding Essentials". It has a lot of good info for a beginer.

Hank

[paulrbrown]

For out of Position welds, welders max capacity can be to great to control. those big bad rods don't like to go uphill and overhead....I find 1/8" to work well and for me are easier to control. Before I welded alot, I saw a piece of ships anchor chain that had been welded together, each link 220lbs,12"x30"x7', they said it took 24 hours nonstop welding, I did not believe them at the time, but after study and actual practice, I understood. The chain was 750' long, not easy to move about, they used 2 D11 Cat Doziers.

[paulrbrown]

/That should read[220lbs,12"x30"x7"] still alot of welding, Paul