Stainless steel material center
Stainless steel piping components, selected by grade.
Compare 304/304L, 316/316L, 310, 321, 347, and 904L for industrial flanges, pipe fittings, and valves—then move from material intent to a procurement-ready specification.
- ASTM / ASMESpecification-led supply
- 6 grade familiesOne focused source
- Global projectsExport documentation
Start with the component
Three product routes. One material decision.
Select the product form first, then confirm the material designation, dimensional standard, pressure class, and test requirements.
Flanges
Forged and machined flange solutions for pressure piping, including weld neck, blind, slip-on, threaded, lap joint, and socket weld designs.
Browse flanges 02Pipe fittings
Elbows, tees, reducers, and end caps for welded or specified piping assemblies under applicable material and dimensional standards.
Browse pipe fittings 03Valves
Ball, gate, globe, check, and butterfly valve routes for corrosion-resistant and high-temperature flow-control service.
Browse valvesGrade selector
Compare the six stainless steel families.
Use these selection cues to build a shortlist—not as a substitute for a corrosion, pressure, or code review.
304 / 304L
UNS S30400 / S30403
A widely specified austenitic grade family for general process, food, water, and architectural service. Choose the low-carbon 304L variant when welded fabrication and resistance to sensitization are priorities.
316 / 316L
UNS S31600 / S31603
A molybdenum-bearing grade family with better pitting resistance than 304 in many chloride-bearing and chemical environments. 316L is commonly selected for welded pressure piping components.
310
UNS S31000 / S31008
A high-chromium, high-nickel austenitic stainless grade used where oxidation resistance at elevated temperature is a primary concern. Service temperature, cycling, atmosphere, and design stress must all be checked.
321
UNS S32100 / S32109
A titanium-stabilized austenitic stainless grade selected for welded components and service involving sensitization-range temperatures. It is often evaluated for thermal cycling and elevated-temperature piping.
347
UNS S34700 / S34709
A niobium-stabilized austenitic stainless grade considered for welded pressure equipment and sustained elevated-temperature service. It can be specified where post-weld stability is important.
904L
UNS N08904 · EN 1.4539
A high-alloy, super-austenitic stainless grade developed for demanding corrosive media. Its nickel, molybdenum, and copper content makes it a candidate for selected acid and chloride duties after a full corrosion review.
Quick comparison
Match the grade to the dominant service risk.
Temperature and corrosion performance depend on the complete environment. Review concentration, contaminants, flow, crevices, cycling, fabrication, and cleaning conditions.
| Grade | Primary selection cue | Common project context | Procurement note |
|---|---|---|---|
| 304 / 304L | General corrosion resistance and fabrication | Water, food, hygienic, and general process service | Confirm 304 versus low-carbon 304L after reviewing welding. |
| 316 / 316L | Improved pitting resistance versus 304 | Chemical, coastal, and moderate chloride exposure | Do not treat “marine grade” as a complete corrosion assessment. |
| 310 | Oxidation resistance at elevated temperature | Furnaces, hot gas, and thermal processing | Verify atmosphere, thermal cycling, and code allowable stress. |
| 321 | Titanium stabilization | Welded and cyclic high-temperature equipment | Confirm product-form availability and applicable material grade. |
| 347 | Niobium stabilization | Refinery and sustained elevated-temperature service | State stabilization, heat treatment, and testing requirements. |
| 904L | High-alloy corrosion resistance | Selected acid, chloride, and severe process environments | Justify with corrosion data, fabrication plan, and life-cycle cost. |
Engineering note: This comparison is an initial procurement guide. Material suitability must be confirmed by the responsible engineer against the applicable design code and actual service conditions.
RFQ readiness
Turn a grade choice into a quote-ready specification.
A precise request reduces substitutions, clarification cycles, and commercial comparison errors. Send the same technical basis to every bidder.
Send your requirement to SASA FLANGE- 01Component and quantity
Flange, fitting, or valve type; size range; and required quantity.
- 02Material designation
ASTM specification, grade, UNS number, and any project-specific restrictions.
- 03Dimensions and rating
ASME, EN, DIN, or project standard; schedule or bore; class; facing; and end connection.
- 04Service conditions
Fluid, concentration, contaminants, design pressure and temperature, and operating cycle.
- 05Inspection and records
Material certificates, PMI, NDE, pressure testing, marking, traceability, and third-party inspection.
Standards map
Separate material requirements from dimensions and ratings.
The purchase specification normally combines a material standard with the dimensional or pressure-rating standard for the component.
Forged or rolled alloy and stainless steel flanges, forged fittings, valves, and parts.
Material · Wrought fittingsASTM A403/A403MWrought austenitic stainless steel fittings for pressure piping applications.
Material · CastingsASTM A351/A351MAustenitic steel castings for valves, flanges, fittings, and pressure-containing parts.
Dimensions · FlangesASME B16.5Pressure-temperature ratings, dimensions, tolerances, marking, and testing for pipe flanges.
Dimensions · FittingsASME B16.9Factory-made wrought buttwelding fittings.
Design · ValvesASME B16.34Flanged, threaded, and welding-end valves.
Technical FAQ
Answers procurement teams ask first.
Short, direct guidance for early-stage material screening. Final selection remains a project engineering decision.
What is the difference between 304 and 304L stainless steel?
304L has a lower maximum carbon content than 304. That lower carbon level helps reduce sensitization risk in many welded fabrications. The final choice must still match the governing material specification, design code, heat treatment, and service conditions.
When should 316L be considered instead of 304L?
316L contains molybdenum and generally offers better resistance to pitting than 304L in many chloride-bearing environments. Chloride concentration, temperature, crevices, cleaning chemistry, and expected life should be reviewed before selection.
Which stainless steel grade is suitable for high-temperature piping?
310, 321, and 347 are commonly evaluated for elevated-temperature duties, but they solve different problems. 310 is known for oxidation resistance, while 321 and 347 are stabilized grades. Allowable stress, thermal cycling, atmosphere, fabrication, and the applicable code determine the final choice.
Is 904L always a better choice than 316L?
No. 904L is a higher-alloy material intended for more demanding corrosive conditions, but it also changes cost, availability, welding practice, and project controls. A documented corrosion and life-cycle review should justify its use.
Can the same grade be specified for flanges, fittings, and valves?
A piping system may use a consistent alloy family, but each component form can have a different ASTM grade designation, manufacturing route, dimensional standard, pressure rating, and testing requirement. Confirm compatibility across the complete pressure boundary.
What information is needed for a stainless steel component quotation?
Provide the product type, material grade and specification, size, schedule or bore, pressure class, facing or end connection, dimensional standard, quantity, testing and certification requirements, and the intended service conditions.
Build the right pressure boundary
Have a grade, data sheet, or service condition?
Send your component list and project requirements. Our team will help align material, product form, standard, and documentation before quotation.