GTAW · Stainless steel
ER347
The stabilised stainless torch rod, used on 321 and 347 base metals and wherever the joint will spend service time in the carbide precipitation range.
What the designation means
- ER
- Classified as both an electrode and a hand fed filler rod.
- 347
- An 18-8 austenitic composition stabilised with niobium, which combines with carbon before chromium can form carbides at grain boundaries.
At a glance
| Process | GTAW |
|---|---|
| Family | Stainless steel |
| Positions | All positions |
| Polarity | DCEN |
| Shielding | Welding grade argon at the torch, with an argon back purge to protect the root |
| Minimum tensile strength | 75 ksi |
Typical uses
- Root and fill passes on 321 and 347 stainless piping
- High temperature process equipment that would otherwise sensitise
- Repairs on stabilised stainless vessels and exhaust systems
How it runs
- Niobium stabilisation protects corrosion resistance after elevated temperature exposure
- Slightly more fluid than the plain 308 rod at the same current
- Small retained ferrite content resists solidification cracking
- Root passes need a back purge to avoid a sugared underside
Storage and handling
Keep rods in the original tube in a clean dry area, away from carbon steel grinding dust that would contaminate the deposit.
Compare with
GMAWER308LThe standard stainless filler for 304 and 304L base metal, with a small amount of retained ferrite in the deposit to guard against solidification cracking.SMAWE347-16A stabilised stainless rod that keeps its corrosion resistance even after long exposure in the carbide precipitation range, which low carbon grades alone cannot always do.GMAWER316LThe molybdenum-bearing stainless filler used wherever chlorides or process acids would pit an ordinary 18-8 deposit, matched to the 316 and 316L base metals.