Welding RA 321 with E347T1-4, FCAW help...

By MetalGirlie Date 12-05-2011 23:01

I'm welding a torque tube and truss assembly for a gas-turbine damper blade, trusses mostly 3/16, some 1/4" w/ 3/4 rod and torque tube is sched. 40 (@1/2" thick) & stiffeners are from 1/2" plate. The first time I welded with 321/347 I literally cried. Running the machine in the same volt/wfs ratio as regular 304 was blowing holes in 3/8 plate on the vertical. Since researching the composition, etc, I've found that running @ 100 fewer ipm yields a more stable puddle and no more blow-outs... But what a pain in the a$$!!! Anyone ever work with this stuff? I'm currently running at 24.3 volts with a wfs @ 200+, shielded with A/C-25 @ 40 psig, and my tip flush with the nozzle, which will lay a nice looking bead (most of the time, grrrrr) with good color but its outside of a spray-arc transfer range, so I'm dealing with some spatter. We also seem to get occasional wormholes/porosity when its hot. I almost get a spray-transfer if I angle the gun straight to slightly ahead (a la mig) instead of drag like traditional flux-core. I don't know what else to do; everything I'm trying seems to work MOST of the time. I'm looking for consistancy of perfection? Perhaps, but consistancy of satisfaction would thrill me at this point. Is there anything else I can do? Anything I should stop doing? My priority, obviously, is respect to the material for a 'healthy' weld, not just pretty. I can't find any settings specific to 321 with 347 wire, so this has all been trial & error... Thanks for any help!
:cry:

By Lawrence (*****)

Date 12-05-2011 23:41

Here is a data sheet

http://products.esabna.com/EN/home/filler_metals_catalog/filler_metals_product_detail/q/display_id.id4367f2a9652111.43048216/category_id.776/path.filler_metals_cored_wire_stainless_steel_gasshielded_flux_core_shieldbright_347_e347t1

You sound like your in the ballpark already.

That push angle in the flat and horizontal is tempting but will prolly not get you fusion at the root.... But with 3/8 plate and a good fitup you should be able to run horizontal and flat at the upper end of the range with .045 wire.

The verts may require settings at the lower end of the range... That's pretty typical.

Try recessing your contact tip 1/8 into the nozzel and running your shield gas @ 35-40 CFH... Keeping your stickout between 1/2 and 3/4" You may find a sweet spot here in the verticals that will be important to keep... perpendicular to a very slight push angle for the uphill. Too much push and you can end up with a "digging" effect.

The "hole punching" in the vert position with FCAW can sometimes be attributed to arc-blow... (But this is stainless Lar, how can this be?).... If your work is fixtured in steel restraint you may have some magnitisim that will cause all kinds of problems in vert that you won't see in horiz or flat.

A quick way to demag your fixturing is to set up some scrap steel someplace on your fixture and run stringer beads with SMAW and alternating current.. Run a few passes and then move the work clamp to a different part of the fixture... When the work clamp has been attached to all the various points, and beads run, the fixture may perform much better... Maybe worth a try as a last resort.

By MetalGirlie Date 12-06-2011 03:21

I am using Shield Bright .045; thanks for the link. I had been to Esab, but missed that. I've been getting pretty good-looking verticals (providing I'm not draped on my belly sideways - LOL) since my first unit of 321 w/347. We were splicing house-bent channel, some 1/4 some 3/8, and I was @ 25+ volts pushing @275-300 ipm which is usually fine for 304 (a little less heavy-handed on 316, maybe) but was just obliterating the 3/8" 321 @ halfway up (I literally cried in frustration as I healed every keyhole and picked up my grinder). Looking it up that night, I learned that 321 loses nickel in the weld puddle, creating surface heat, so I thought less wire=less consumption=less heat generated in the weld puddle, which had seemed to work for running a successful bead in the vertical, even without 'walking' it, and I could push @ 25 more ipm for flats. I recently found info on its titanium stabilization and the Ti loss/Nb exchange when you use E347T. This current unit is much smaller and uses almost all 3/16 and a little 1/4". With exception to the torque-tube, a 92"l, 12" O, sched 40 (I think- @ 1/2" thick wall) pipe with 1/2" stiffener rings for the truss mounts, flanged with 1-1/2" plate flanges that will bolt it to the drive assembly. On that, I ran 24.5/250-275. I haven't found that sweet spot of spray transfer, yet, with this stuff. Although, with stainless & me, lower ranges usually end up globular transfer; I never seem to find spray transfer until 25.5+ v and above. I am afraid to run that hot on such a lightweight unit, from my previous experience, so I've been dealing with the extra pick-up. This unit doesn't have 'enough' to hide a bad weld. Don't ask about overhead- so sloppy you can barely see your bead.
Lawrence, you just blew me away; I've never heard of arc-blow! I hadn't looked it up before starting my reply, sooo... Wow. I never, ever thought of that. Our work surfaces are largely carbon with stainless cladding- inventory drops of plate or channel, carbon channel/angle horses, etc. I don't know if we have a stick machine... We must, I just don't know. We're all wire-fed and TIG processes. I found this forum through still researching this alloy, as I'm working it again and havent beaten it yet, as far as I'm concerned. There are three units in all, so I'll get plenty more practice. I'll keep playing with the wire, re-check my gas. My friend who flanged the drive /idler shafts was wondering if there was any gas other than c-25 recomended? Everyone at work who's ever welded 321 with 347 tells me how crappy it is, so you can see why I'm STILL seeking help. Thanks for all your advice and the links. I appreciate your reply.

By Lawrence (*****)

Date 12-06-2011 14:41

You can do the same demag thing with AC Tig

Let us know how this problem goes for you.

And when your finished with that project, here is something you can think about, courtesy of the AWS

http://www.wonderwomencasting.com/

You could be a star.

By ravi theCobra (**)

Date 12-06-2011 17:48

Simple , simple moi !

I saw casting and thought it was a foundry ! !

This is just a fu fu Holywood picture outfit , looking for the next Kim Kardashian.

When you meet a REAL woman who has done and is doing the work please do not insult her with these kind of things -

By Lawrence (*****)

Date 12-06-2011 18:14

Wow Ravi... Very quick to judgement there aren't you?

I found the link on the AWS official facebook page.

It's a reality show based on succsessful females who work in non-traditional areas.

http://www.facebook.com/AmericanWeldingSociety

No insult was intended.

But thanks Ravi hijacking the thread and telling me how to run my life.

By MetalGirlie Date 12-07-2011 02:45

Simmah Down Now, kids. LOL Lawrence may have just been trying to lighten my mood with either a joke or a compliment... I can take both. Ravi, I thought the same, casting=foundary, at first! Hehehe... As you can tell by my previous post, I can geek-out HARD about my work, sometimes... A diversion is good.
I gave myslf a bit more wire and laid down a few, but got pulled off my job to help get something else out the door. There's always tomorrow...

By Dualie

Date 12-07-2011 05:48

i had a problem with arc blow on a repetitive use fixture years ago. I found that splitting my ground into a Y and hooking it to both sides of the table seemed to help.

That AC idea sounds like a great solution too. You can run AC rod on your TIG power source