Stainless application
Stainless Steel for Chemical & Process
Chemical service is a corrosion problem before it is a piping problem. The fluid decides the grade: chlorides push you from 304 to 316L, and from 316L to 2205 duplex once temperature and stress join in.
Specification
What Chemical & Process Specifies
| Grades normally used | 316L · 2205 · 304 |
|---|---|
| Product forms | Seamless tube · Fittings · Flanges · Plate |
| Standards & approvals | ASTM A312 (pipe) · ASTM A182 (fittings) · ASTM A790 (duplex pipe) · EN 10216-5 |
Grade by grade
What Each Grade Does in Chemical & Process
A stainless application page that lists grades without saying what each one is for is a catalogue, not a specification. These are the roles they actually play here.
| Grade | The job it does here | Detail |
|---|---|---|
| 316L | The default for most chemical and process lines. Molybdenum handles the chlorides and the low carbon keeps the welds sound — specify the L grade for anything welded. | Specs → |
| 2205 | Where the fluid is hot, stressed and chloride-bearing. Roughly twice the yield of 316L and resistant to stress-corrosion cracking that cracks the austenitic grades. | Specs → |
| 304 | General chemical duty without chlorides — acids and alkalis at moderate temperature where the extra molybdenum in 316L buys nothing. | Specs → |
Before you send the enquiry
Specification Mistakes That Cost Money Here
None of this is exotic. All of it arrives on real enquiries, and each one adds a round trip before a price can be issued.
1. Specifying "stainless" without a grade. In chemical service that is not a requirement; 316L to ASTM A312 with a stated wall schedule is.
2. Ordering 316 instead of 316L for a welded line. The carbon difference (0.08% vs 0.030%) is the difference between a line that lasts and one that sensitizes at the weld.
3. Ignoring the chloride level in the fluid spec. Chlorides are what move you from 304 to 316L to 2205 — leaving them off the enquiry means quoting the wrong grade.
4. Omitting the design temperature. Austenitic grades stress-corrode above about 60 °C in chloride service; without the temperature the grade decision cannot be checked.
Categories that serve it
What We Supply Into Chemical & Process
Stainless Steel Coil
Cold-rolled and hot-rolled coil in 200 / 300 / 400 series.
Stainless Steel Sheet & Plate
Cold-rolled sheet and hot-rolled plate for structural and decorative use.
Stainless Steel Tube & Pipe
Seamless and welded round, square and rectangular tube.
Stainless Steel Bar & Rod
Round, flat, square and hexagonal bar, cold drawn or hot rolled.
Verification
What We Put in Writing for This Application
- Mill test certificate to the class your file requires — 2.2 or 3.1 — carrying the actual composition and mechanical values for the heat, so the grade is checkable against the order.
- Surface finish and gauge recorded before packing; photos of the sealed container.
- Where the market requires it, the food-contact, 3-A or coating test report with the issuing body named.
Before you ask
Chemical & Process — Questions That Come Up
When is 2205 worth the cost over 316L?
When the fluid is both hot and chloride-bearing, or when the design is load-bearing and corrosion-exposed. 2205 doubles the yield strength and resists stress-corrosion cracking that cracks 316L. For cold, mildly chlorinated service, 316L usually does the job for less.
Why specify 316L instead of 316 for welded lines?
The carbon limit: 316L caps carbon at 0.030% so the weld does not sensitize. "316" on a drawing does not guarantee the low-carbon grade, so write 316L explicitly for anything that will be welded.
What standard should chemical pipe be ordered to?
Seamless to ASTM A312 or EN 10216-5; duplex pipe to ASTM A790. Fittings follow ASTM A182 or the matching EN grade. Name the standard and the wall schedule, not just the size.