Code-governed work
Use the contract code, qualified WPS, qualified personnel and required inspection.
Technical guide
How to Weld Stainless Steel
A sound stainless weld starts with the governing code and a qualified welding procedure, not a generic machine setting. Confirm grade, joint, thickness, service and acceptance requirements first.
Control documentWPS and supporting qualification
Key risksContamination, heat input and distortion
Release basisInspection to the governing code
Decision summary
Select the welding route from service requirements
Structural, pressure, sanitary, decorative and repair welds have different governing rules. The correct process and filler depend on base metals, thickness, joint and service.
Thin or appearance-critical work
Control fit-up, heat input, sequence, shielding and distortion before chasing cosmetic finish.
Dissimilar or unknown alloys
Identify both base metals and have welding engineering approve filler and procedure.
Reference table
Common welding decisions before arc start
This comparison helps define the procedure scope. It does not replace WPS qualification or the filler manufacturer recommendations.
| Decision | Questions to answer | Why it matters | Record on |
|---|---|---|---|
| Governing requirement | Structural, pressure, piping, sanitary, customer or repair code? | Controls qualification, inspection and acceptance | Contract and WPS |
| Base metal | Exact grade, product form, condition and traceability? | Drives filler, heat treatment and metallurgical risk | MTC and material map |
| Joint and thickness | Design, root access, restraint, position and range? | Controls process, parameters and distortion | Drawing and WPS |
| Filler and shielding | Classification, diameter, gas and backing/purge need? | Affects weld metal chemistry and oxidation | WPS and consumable control |
| Heat and sequence | Preheat/interpass limits, travel, passes and restraint? | Affects distortion, sensitization and duplex phase balance | WPS and weld log |
| Post-weld condition | Heat tint removal, passivation, finish and NDE? | Restores surface condition and demonstrates acceptance | ITP and final report |
Use the latest contract-specified edition of the applicable code and consumable specification.
Need a welding RFQ, not a generic setting?
Send the grade, joint drawing, thickness range, governing code, service, inspection and finish requirements.
Working method
Build and execute the weld around the qualified procedure
Procedure qualification, material control, clean preparation and recorded inspection are more reliable than copying amperage from another job.
Confirm code and materials
Identify the governing document, both base metals, thickness range, joint and service condition.
Approve WPS and consumables
Use qualified parameters and controlled filler, shielding and purge materials for the stated range.
Prepare without contamination
Use dedicated stainless tools, clean the joint and keep chlorides, oils, paint and carbon-steel particles away.
Weld, clean and inspect
Control sequence and interpass condition, remove unacceptable heat tint as specified, then inspect to the contract.
Limits and escalation
Escalate these conditions to welding engineering
Duplex and highly alloyed grades
Heat input, interpass temperature and filler selection can affect phase balance and corrosion resistance.
Dissimilar-metal joints
Dilution and service environment require engineered filler and procedure selection.
Pressure or regulated service
The governing construction code controls qualification, inspection and documentation.
Unknown repair material
Positive material identification and damage assessment may be needed before a repair WPS is selected.
Visual process context
Separate the welding setup from the acceptance evidence.
Use two context images to make the joint geometry, welding route and inspection record clear before work is released.
Interactive planning aid
Identify the minimum welding-control package
Choose the application class to see the first documents and checks to request.
Frequently asked questions
Stainless steel welding FAQ
Both processes can be suitable when the qualified procedure, joint, thickness, shielding and filler match the application. Process choice alone does not establish weld quality.
Filler selection depends on the exact base-metal grades, service, dilution, code and procedure. Use the WPS and consumable manufacturer data rather than a generic chart.
For joints where the root is exposed to air, controlled backing gas can limit oxidation. The required purity, flow and acceptance depend on the procedure and service.
The contract, service environment and finish requirement should define acceptable discoloration and post-weld treatment. Industry guidance notes that post-weld cleaning can be important for corrosion resistance.
Method, sources and review
Traceable sources and review status
Official AWS committee page listing the Structural Welding Code - Stainless Steel.
Industry welding, fabrication and post-weld-cleaning resources.
Detailed industry guidance on preparation, contamination, distortion and post-weld cleaning.
Official cleaning, descaling, pickling and passivation context for stainless fabrication.
Welding is safety-critical work. A qualified welding engineer or responsible code professional must approve the procedure, qualification range and acceptance criteria for the actual application.
Welding control context
Make the joint and inspection route visible.
A reliable welding brief identifies material condition, joint preparation, filler selection, heat input, post-weld treatment and the evidence required for final acceptance.
- Joint detail
- Heat control
- Acceptance evidence