Welding with Flux Coated Stainless filler wire

By woodman17086 Date 01-10-2009 16:19

I have a job prospect welding Schedule 40 30" Stainless 304 pipe with Flux coated filler wire. I've never used it before and we've had more than 30 men fail X-Rays on the job and ultimately have been removed from the job. I'm told I'm next on the list to give it a shot. I was hoping for some pointers to make this a successful aadventure!

I've read about the wire and amperage ranges. Now I need some pointers on the actual process. Any Info would be appreciated especially any documentation on the process.

By upten

Date 01-12-2009 01:07

use a big enough gap to place your wire on the inside of the pipe. i have used it on 18 inch pipe .mostly in papermills. you only use this on the root pass.

By spgtti

Date 01-16-2009 03:09

Definitely open up your gap otherwise the flux on the wire prevents you from getting any kind of internal root reinforcement. Welds like crap but works better than solar-flux.

By scrappywelds (***)

Date 01-28-2009 23:29

wlds best when the gap is opened up to weld from the inside. then grind out the slag like a 6010 root. last flapper wheel off the smoke oxidation around the heat affected zone. welded hundred pounds of this type of wire, alot better than solar flux in my opinion.

By spgtti

Date 01-29-2009 02:19

It should be called solar-sux. That stuff is a sham. I spent all day battling a fit and root in a piece of 26" sch10 304ss.

By mightymoe (**)

Date 01-30-2009 02:11

would it have been faster to tig all the way?

By upten

Date 02-01-2009 21:27

this is a tig welding process . with flux coated wire . no need to purge the pipe

By js55

Date 02-07-2009 15:57

Manufacturers recommend keyholing but the coated stuff can be welded fine by consistent feed without keyholing. Widen the gap like suggested. You have to allow enough room for the flux to flow easily onto the ID or your wasting your time on SS. If the root isn't covered it will never hold up under corrosive service.
This stuff takes some skill. A few days of practice for skilled welder to get it right.
The other thing is, depending upon skill level run a double hot pass concentrating the heat on the sidewall. If you don't you will oxidize the root and you've wasted your effort again. If you feather edge instead of the recommended landing you will find your root is heavier and you will less likely oxidize the root. This may also allow a skilled welder to run a single hot pass but I wouldn't recommend it until you've done this awhile and have a feel for the results.
This stuff actually holds up well under ASTM A262 Practice E (copper-copper sulfate-16% sulfuric -Straus Test) if done right. Which suprised me.
I wouldn't think of this stuff as a replacement for purging though. Use it only when purging is impossible or at least extremely inconvenient and engineering has approved it for the intended service.