316L / UNS S31603 is a common low-carbon molybdenum-bearing stainless steel flange material for process, petrochemical, food, pharmaceutical, heat-transfer, and general industrial service.
316L / Flanges / UNS S31603
Stainless Steel 316L Flanges Manufacturer & Exporter
Raymond Tube Industries manufactures, supplies, and exports Stainless Steel 316L / UNS S31603 flanges to ASTM A182 / ASME SA182 for process piping, petrochemical, marine, and general corrosion requirements. Buyers can define weld neck, slip-on, blind, socket weld, threaded, lap joint, long weld neck, or drawing-based forms with NPS, class, bore or schedule, facing, inspection, documentation, packing, quantity, and destination.
Material description
316L material and product scope.
Start with material identity, then define the flange or fitting form, dimensions, inspection, documentation, and packing requirements for quotation.
The commercial advantage is availability and broad standards familiarity, but the page keeps chloride, hot seawater, crevice, and SCC exposure under engineering review rather than treating 316L as universal.
For flange orders, ASTM A182 / ASME SA182 F316L must be paired with ASME B16.5 dimensions, pressure class, facing, bore, certificates, and packing requirements.
| Specification | Verified value | Unit |
|---|---|---|
| ASTM standard | ASTM A182 for forged or rolled stainless steel flanges | - |
| ASME material standard | ASME SA182 | - |
| UNS | S31603 | - |
| Sizes | ASME B16.5 reference scope: NPS 1/2 through NPS 24; larger flanges require ASME B16.47 or drawing review | - |
| Pressure classes | Class 150, 300, 400, 600, 900, 1500; Class 2500 within B16.5 size limits | - |
| Schedule / bore | Buyer to specify matching schedule, bore, hub, and weld-end details | - |
| Facing | RF and RTJ where compatible with flange type, class, gasket, and project specification | - |
| Dimensional references | ASME B16.5, ASME B16.47 review, ASME B16.36 for orifice flange packages | - |
Sizes and configuration
Open the dimensional table that matches the buying decision.
The full reference tables remain available for engineering review. Start with the size family and dimensional standard that apply to the RFQ.
Product forms
Flange forms for specification-led buying.
Every form is a quotation signal: it controls standard selection, dimensional review, inspection, packing, and the drawing or piping-class details needed before offer.
WNRF
Weld neck raised face flanges for butt-welded piping where bore, schedule, and pressure class must align.
WNRTJ
Weld neck ring type joint flanges for RTJ gasketed joints in higher-integrity pressure service.
SORF
Slip-on raised face flanges where project specifications permit fillet-welded slip-on construction.
BLRF
Blind raised face flanges for line isolation, nozzle closures, and test-boundary requirements.
BLRTJ
Blind ring type joint flanges where the selected pressure class and gasket system require RTJ geometry.
Socket Weld
Socket-weld flanges for small-bore lines when allowed by the piping class and owner specification.
Threaded
Threaded flanges for non-welded connections where service, pressure, and code rules permit threads.
Lap Joint
Lap joint flanges used with stub ends where rotation and alignment flexibility are required.
Long Weld Neck
Long weld neck flanges for vessel nozzles, thick-wall transitions, or engineered drawing-based supply.
Orifice
Orifice flange packages requiring ASME B16.36 review, tap details, class, facing, plugs, and documentation.
Dimensional standards
Size, class, facing, schedule, and bore are separate commercial decisions.
The page presents standards as quotation routes. The final offer must follow the buyer's piping class, drawing, and approved dimensional basis.
Primary flange dimensions
ASME B16.5 for NPS 1/2 through NPS 24 flanges within the listed class coverage
Large diameter review
ASME B16.47 or drawing-based route to be confirmed before quotation for sizes beyond B16.5
Facing and bore
RF, RTJ, bore, schedule, gasket surface, and finish must follow the piping class or drawing
Chemical composition
Published chemistry reference.
Use the material test certificate and ordered standard to confirm the chemistry of the delivered product.
| Element | Verified composition | Basis |
|---|---|---|
| Chromium | 16.0-18.0 | Mass % |
| Nickel | 10.0-14.0 | Mass % |
| Molybdenum | 2.00-3.00 | Mass % |
| Manganese | 2.00 max | Mass % |
| Silicon | 0.75 max | Mass % |
| Nitrogen | 0.10 max | Mass % |
| Phosphorus | 0.045 max | Mass % |
| Carbon | 0.030 max | Mass % |
| Sulfur | 0.030 max | Mass % |
| Iron | Balance | Mass % |
Mechanical properties
Mechanical data with product-form context.
The table avoids undocumented product guarantees. Final conformance is tied to ASTM/ASME route and certificate review.
| Product form | Yield / proof strength | Tensile strength | Elongation / hardness |
|---|---|---|---|
| Plate, sheet, strip | 170 MPa / 25 ksi min | 485 MPa / 70 ksi min | 40% min; 95 HRB max |
| Tube and pipe at 20 deg C | >=220 MPa Rp0.2; >=250 MPa Rp1.0 | 515-690 MPa | >=45% A; >=35% A2 in; <=90 HRB |
| Bar at 20 deg C | 205 MPa Rp0.2 min; 240 MPa Rp1.0 min | 515-690 MPa | >=40% elongation; max 215 HBW |
Applications and corrosion considerations
A commercial page with engineering discipline underneath.
Applications help qualify the enquiry, while corrosion notes flag the review questions that must be resolved before substitution or service approval.
Process piping
Petrochemical plants
Food and beverage lines
Pharmaceutical utilities
Pulp and paper systems
Heat exchanger nozzles
Marine hardware in moderate environments
General corrosion-resistant flange packages
General corrosion
316L has published resistance in many organic acids, selected inorganic-acid ranges, and salt solutions, but contaminants and temperature can change suitability quickly.
Pitting and crevice corrosion
Molybdenum improves localized corrosion resistance compared with 304/304L, yet hot chloride and stagnant crevice conditions still require engineering review.
Intergranular corrosion
Low carbon content improves resistance to intergranular corrosion after welding compared with higher-carbon 316 variants.
Stress corrosion cracking
Austenitic 316L remains susceptible to chloride stress corrosion cracking under tensile stress and elevated temperature; duplex grades can be considered where SCC resistance is central.
Inspection, packing, documentation
Conversion depends on confidence at release.
The product page turns buyer concerns into explicit RFQ controls: PMI, MTC, TPI, NACE or IGC review, packing protection, and document release.
Genuine RTI evidence
Finished flange range
RTI component photography supporting product-form, facing, bore, marking, and release-document review. Material grade is confirmed through heat traceability and the agreed release documents, not visual appearance alone.
PMI
PMI helps prevent mix-ups between 304L, 316L, 317L, 904L, duplex, super duplex, and nickel alloy flanges.
MTC
MTC review should confirm UNS S31603, F316L route, chemistry, mechanical values, heat number, and marking.
TPI
Third-party inspection can cover dimensions, marking, visual inspection, documents, packing, and final release.
IGC
IGC testing or review should be added where project specifications require proof against intergranular attack.
Surface protection
Machined faces, gasket surfaces, threads, and bevel ends are protected according to the packing instruction.
Traceable marking
Heat numbers, grade, size, class, standard, and item tags should stay readable through packing and receipt.
Export packing
Wooden case, pallet, moisture barrier, separation, and destination marking requirements are captured at RFQ stage.
EN 10204 3.1
Specify inspection certificate type where the buyer requires manufacturer-issued lot traceability.
Dimensional record
Add dimensional inspection reports for machined flanges, RTJ grooves, bores, bevels, and fitting geometry where required.
Inspection dossier
PMI, MTC, TPI release, NDE, packing list, marking photos, and origin/export documents can be compiled into one dossier.
Commercial FAQs
RFQ questions for Stainless Steel 316L Flanges.
Answers focus on the details procurement and engineering teams should define before requesting a quotation.
Related pages
Continue the buying path.
Compare related material grades, product forms, and engineering guidance before finalising the RFQ.
Stainless Steel Flanges overviewReview the authoritative stainless steel flanges product-family route.316L material dataReview UNS S31603 material data and related product standards.Super Duplex S32750 flangesCompare the severe chloride upgrade route.Inconel 625 flangesCompare a nickel alloy flange route.
Technical quotation
Have a requirement?
Send the material, size, class or schedule, quantity, and applicable specification. RTI's export team will receive the technical enquiry route.
