Most instrument lines never see anything more aggressive than air, water, or oil. For those runs, paying for molybdenum is paying to solve a problem you don't have, and that's the whole case for 304 coiled tubing: the lowest-cost stainless coil that still gives full corrosion resistance in general service. USA Piping Solution supplies SS 304 and 304L coiled tubing to ASTM A269 and A213, seamless and welded, in continuous coils up to 2,000 metres with no intermediate joints. The moment chlorides enter the picture, coastal air, marine spray, brackish water, step up to our Stainless Steel 316 Coiled Tubing page instead.
Where 304 Is Enough, and Where It Isn't
| Service | 304 Verdict |
|---|---|
| Instrument air, nitrogen, inert gas lines | Yes, the standard choice |
| Fresh water, demineralized water, steam condensate | Yes |
| Food, dairy, brewery process lines | Yes, 304's signature non-instrumentation use |
| Oils, fuels, and most indoor plant utilities | Yes |
| Coastal or marine atmosphere, deck installations | No, chloride pitting risk, use 316 |
| Chloride-bearing process fluids, brackish or salt water | No, use 316 or duplex |
| Sustained service above roughly 425°C with thermal cycling | Use 321 or consult on grade |
The rule of thumb: if the line lives indoors and never touches chlorides, 304 saves money with nothing given up. Anything salty, coastal, or chemically aggressive belongs on the 316 page. The full grade family is compared on our Stainless Steel Coil Tubes & Coiled Tubing hub.
Applications
- Instrument Air & Gas Distribution: plant-wide pneumatic and analyzer supply lines.
- Food, Dairy & Brewery Lines: process and CIP lines where 304's cleanability is the industry standard.
- Water & Utility Runs: fresh water, DI water, condensate, and general plant utilities.
- Heat-Transfer Coils: immersion coils in non-chloride baths; see Heat Exchanger Tubes & Pipes for the wider range.
- Pre-Insulated Tubing Bundles: the economical core for steam-traced instrument bundles in non-corrosive service.
Testing, Certification & Availability
Every coil is 100% tested, hydrostatic or eddy-current per the governing standard, with mill test certification and heat traceability; see our Quality Policy page for the full program. 304/304L is the most commonly stocked coil grade and typically ships fastest. Send us your OD, wall, and run length for current availability.
Related Products
- Stainless Steel 316 Coiled Tubing
- Stainless Steel Coil Tubes & Coiled Tubing
- Stainless Steel Pipes & Tubes
- Heat Exchanger Tubes & Pipes
Frequently Asked Questions
Should I order 304 or 304L coiled tubing?
If the tubing will be welded at termination, 304L (or dual-certified 304/304L, which most mills supply as standard) avoids weld-zone sensitization. For purely mechanical fitting connections, either works; pricing is usually identical.
Can I use 304 coiled tubing outdoors near the coast?
Not recommended. Airborne chlorides in coastal atmospheres cause pitting and tea-staining on 304 over time. Use 316 coiled tubing for any marine or coastal exposure.
What's the longest single 304 coil you can supply?
Up to 2,000 metres without an intermediate weld for smaller diameters; maximum length shortens as OD and wall grow. Send your size and we'll confirm.