SMAW Stainless Steel

By pipewelder_1999 (****)

Date 01-16-2003 18:27

1) Yes
2) No
3) Yes
4) Stringers
5) I have used small diameter 5/64" and 3/32" Avesta and Sandvic

The fitup is very critical and this is really a pain compared to GTAW. The advantage for doing this was welding the root pass in a composite (SA210 A-1 Core with 304/8 clad) window weld. The SMAW process is better suited for these type of welds since the joint is welded through an opening (Window) cut in the tube. This opening doesnt always lend itself to sticking a tig rig and wire and being able to see whats happening.

Some of the electrodes I have used made me feel like I was a good stainless welder and others made me wonder if I had spent the last 20 years of my life in the wrong trade.

Small stringer beads are the preferred method. Some people have fine looking welds using a weave but SS doesnt need to stay hot any longer than needed so I suggest stringers.

The thickness of the base metal can affect your ability to stick weld SS. The thicker, the easier. The more energy that can be absorbed by the material, the faster the puddle cools off. The faster it cools, less time to sag.

My last experience with SMAW SS was typical of the 2nd situation described 3 paragraphs above so I may not be much help!

Have a nice day

Gerald Austin
www.weldinginspectionsvcs.com

By TimGary (****)

Date 01-16-2003 19:20

I have only SMAW welded Stainless a few times years ago. The one thing that I remember most about it, other than it's un-cooperative nature, is that you need a jackhammer and dynamite to remove the flux.
However, it may have had something to do with the fact that I was a poor, inexpierienced welder at that time.
I would recommend that you try it out before you buy into it. GTAW or MIG would be more cost effective, in my opinion.
Tim

By pipewelder_1999 (****)

Date 01-16-2003 19:57

I keep telling myself that now that I'm old and experienced, I can handle vertical SMAW SS. Usually by the time I'm done, I' thinking about using that "Well I don't see as good as when I was young" excuse.

G Austin

By Seldom

Date 01-17-2003 00:13

I haven’t posted in quite a while but this topic has a special interest for an old retired fella that remembers when all position, open root SMAW SS was a requirement for Journeymen Welder status.

Pipewelder_1999 is correct in all of his answers but I do have a little more info to add.
First off, the electrode manufacturers will tell you that their SS, SMAW electrodes aren’t designed for open root applications. If they do today, then they’ve changed their minds in the last 10 years! That’s the main reason folks have such great difficultly in successfully running one that will repetitively and consistently satisfy ASME Sec. IX requirements.

In order to consistently satisfy most quality requirements, the welder needs to apply the root bead using a technique far different then they do with a CS electrode. Some welders develop a knack for applying SS and nickel-base alloy open root beads with SMAW and some never are able.

With a 3/32” land and gap, apply the root with a fast side-to-side wiggle while maintaining a pretty fast forward travel speed. You have to touch the sides of the joint with the wiggle but DO NOT linger there! You need to develop a “keyhole” but you will need to learn how large of one to have and then the skill to maintain it at the chosen size. It’s of the utmost importance to understand, the size of the keyhole tells the welder how much internal penetration he’s getting. Too big of a keyhole-too much penetration, too small/no keyhole- no penetration! If the keyhole starts getting larger then you want, increase your travel speed. If it gets too big, STOP! Reestablish the arc about a ½” ahead of the keyhole and start applying the root again. Go back after the root has been applied and feather the areas that you skipped and run the short root bead (you can pass radiograph quality requirements this way). Fellow welders and trainees used to call my technique “The Flicker-Pass Root” which pretty much describes how it’s applied and I’ll warn you, it’s hard on wrists!

Open root SMAW SS welding is literally a thing of the past in my old company. GTAW, GMAW, and back-gouging have taken it’s place for two basic reasons. One, because of the high level of skill required to consistently satisfy Sec IX quality requirements. Two, the tenacious, residual slag attached to root face (internal) has been proven to provide an excellent environment for corrosive attack.

Good luck

By welder_guy2001 (***)

Date 01-17-2003 02:45

wow...sounds pretty wild! i welded w/ some SMAW SS only because the TIG machine's gas was empty. it seemed to run a little bit like 7018. but then again, that was on 1/8" SS.

By Michael Sherman (***)

Date 01-17-2003 15:25

Seldom, you have hit the nail on the head. Your technique is a proven one and your reasons for not using this procedure are the same reasons I have spoken out against open root welding with Low-Hydrogen type electrodes. Yes it can be done. Is it a good idea? I have never thought so. There are so many better ways to go and you have listed them.

Mike Sherman

By cccasey (**)

Date 01-18-2003 02:42

Thanks again for your suggestions and answers. I'll try the flicker pass root technique and prep the pipe with a 3/32 root face and opening. All your responses are appreciated.
Pipewellder, do you remember the classification of the electrodes that made you feel like a good welder? I'm feeling like a beginner again with the stuff I had in the bin. E310-16. I did try some specialty down hill rod that worked great but it's $50 per lb. ( A little much for my pocket book to just play around with.)

By pipewelder_1999 (****)

Date 01-18-2003 22:37

IT was a regular -16 electrode. If I remember correctly it was a 308MoSi-16. We also used one that had a trade name P5-PW but I don't remember the classification.

G Austin