Tesco Steel & Engineering manufactures ASTM A182 F316Ti long weld neck flanges — the third answer to the weld question: UNS S31635, W.Nr. 1.4571 / X6CrNiMoTi17-12-2 — with ASME B16.5 or EN 1092-1 flange ends and the barrel made to order. Where 316Lremoves the carbon and 316Hembraces it, 316Ti locks it: titanium at five times the carbon-plus-nitrogen content claims every carbon atom before chromium ever can — the weld zone stays intergranular-safe as-welded, and nothing is surrendered on the certificate: full 316 strength, 515/205 MPa. This is the European classic — the DIN world's default molybdenum stainless, written into continental piping classes for half a century, with a genuine elevated-temperature edge: the titanium lock never expires, and European practice runs 1.4571 to ~550 °C (code creep design belongs to 316H). One forging, one closing weld — stabilised or 316L filler routes, both qualified. The walls stand: chloride SCC to duplex, seawater to the twins, electropolish to 316L. Facings: RF / FF / RTJ. Every lot with EN 10204 3.1/3.2 MTC. ISO 9001:2015, made in Mumbai, India — exported to 50+ countries.
ASTM A182 F316Ti · UNS S31635 · W.Nr. 1.4571The Third Answer — Titanium Locks the CarbonTi 5×(C+N) — The Stabilisation Formula515 / 205 MPa — Nothing SurrenderedThe European Classic — DIN/EN HeritageStable to ~550 °C — The Lock Never ExpiresB16.5 / EN 1092-1 · Class 150–2500EN 10204 3.1 / 3.2 · ISO 9001:2015
ASTM A182 F316Ti Long Weld Neck Flanges — Specifications at a Glance
What is an ASTM A182 F316Ti Long Weld Neck Flange?
The titanium lock, in the nozzle pattern. An ASTM A182 F316Ti flange (UNS S31635, W.Nr. 1.4571) whose neck continues as a long, heavy-walled straight barrel — the nozzle itself — bevelled for one closing butt weld at the vessel or shell. Titanium at 5×(C+N) claims the carbon before chromium can — weld-safe as-welded, with full 316 strength kept: 515/205/30. The European classic: the DIN world's default molybdenum stainless, stable through sustained service to ~550 °C — the lock never expires. C ≤0.08%; Cr 16–18%; Ni 10–14%; Mo 2.00–3.00%. Supplied solution annealed with records. Flange ends per ASME B16.5 or EN 1092-1, Classes 150–2500 / PN equivalents; barrel length and bore stated by you. EN 10204 3.1 on every lot.
Also searched as: F316Ti LWN flange, 316Ti long weld neck flange, 1.4571 LWN flange, S31635 nozzle flange, X6CrNiMoTi17-12-2 flange, titanium stabilised LWN — all the same product. Related pages: the facings — LWNRF / LWNFF / LWNRTJ — the long weld neck hub, the F316Ti socketweld on small bore, the three answers — F316L / F316H — the frame — F316 — the stabilised cousins — 321 / 347 — and the 316 grade hub.
The Weld Question — Three Answers on One Frame
Grade
The Answer
The Trade
Page
F316L
Remove the carbon
Weld-safe, but 485/170 — and the world's commodity
The rule of the three answers: remove, lock, or embrace — the lock keeps the strength the removal surrenders, and never expires the way absence can; the world chose L for cost, Europe kept Ti for reasons this page explains.
What the Titanium Lock Buys
Weld-Safe at Full Strength
515/205 MPa with intergranular immunity — the L route's protection without the L route's 170 MPa yield line; designs that lean on strength get it without dual-certification arithmetic.
A Lock That Never Expires
Titanium carbides are stable where absence is merely improbable — through years of sustained warm service the stabilised structure cannot slowly sensitise, which is why European practice trusts 1.4571 to ~550 °C.
Half a Century of European Plant
The DIN world's default molybdenum stainless — continental piping classes name 1.4571 by habit, and replacement or expansion nozzles on existing systems must match the metallurgy in place.
Both Flange-End Traditions
ASME B16.5 classes and EN 1092-1 PN ratings machined on the same barrels — the grade's European habitat makes dual-standard capability part of the product, not an extra.
Specification Notes — Getting F316Ti Long Weld Necks Right
Three honest notes.Stability is not creep design: the lock keeps the weld zone safe through warm decades, but ASME creep-range allowables belong to 316H's deliberate carbon — long warm corrosion service says Ti, code creep design says H. Hygiene says L: titanium carbide stringers resist electropolishing — pharma and high-polish work belong to 316L. And the ladder's walls stand: stabilisation does nothing for chloride SCC above ~60 °C — that cure is duplex — and the seawater line stays with the super duplex twins.
How Our F316Ti LWN Flanges Are Manufactured
1
Forging — each piece individually forged from certified stabilised heats with the barrel integral — no welded build-ups — in any section up to the heaviest HB patterns.
2
Solution annealing — the cycle that sets the clean austenitic structure with the titanium already holding the carbon; records retained against the heat number.
3
Verification — chemistry per heat with the 5×(C+N) stabilisation arithmetic shown on the certificate; mechanicals per heat; impacts at MDT where cryogenic work requires them.
4
Machining — flange end to ASME B16.5 or EN 1092-1 as ordered; barrel turned to pattern (standard / HB / equal) and bored to the ordered schedule or drawing; RF serrations, flat face or RTJ groove; weld end bevelled 37.5°.
5
Testing & marking — PMI reads the titanium line on every piece — F316Ti and plain 316 can never mix on the shelf; marked with grade, size, schedule and heat number.
6
Certification & packing — EN 10204 3.1 MTC with solution-anneal records (3.2 witnessed on request); WPS guidance covering stabilised and 316L filler routes; faces and bevels protected, packed sea-worthy.
Where F316Ti LWN Flanges Are Used
The European classic's world: chemical and petrochemical plant built to DIN/EN piping classes and their licensees worldwide, replacement and expansion nozzles on existing 1.4571 systems where matching metallurgy is mandatory, warm chloride-bearing columns and exchangers running years between shutdowns, hot-water and steam-adjacent utilities in the band where unstabilised grades slowly sensitise, and export fabrications certified against European material lists. Production and supply below:
Stainless Long Weld Necks — Machined at Our WorksLong Weld Neck — Heavy Barrel, Bevelled Weld EndDN600 RF Long Weld Neck — Large Diameter, B16.5 Drilling
F316Ti LWN Flange Dimensions
Flange-end dimensions are class-governed per ASME B16.5 — or PN-governed per EN 1092-1, the grade's home standard — with barrel length and bore per order. Full class-by-class charts:
Seven elements — the specification tradition decides more here than anywhere:
1
Size & standard — ASME B16.5 or EN 1092-1, stated explicitly — e.g. 6″ NB B16.5, or DN150 EN 1092-1.
2
Pressure class or PN rating & facing — 150#–2500# or PN equivalents; RF, FF or RTJ with ring number.
3
Barrel length — overall, face to weld end: 150 / 230 / 300 mm stock or any stated length.
4
Barrel bore & pattern — pipe schedule to match or finished bore in mm; standard, heavy barrel or equal barrel; weld-end prep if non-standard.
5
Grade line & service — ASTM A182 F316Ti / UNS S31635, or EN 1.4571 where the specification is European; medium, temperature and matching-metallurgy requirements stated — they confirm Ti against 316L across and 316H above.
6
Certification — EN 10204 3.1 with solution-anneal records (our standard) / 3.2 witnessed.
Example: “LWN Flange RF, DN100 EN 1092-1 PN40, barrel 230 mm, bore to DIN pipe 114.3×6.3, standard pattern, EN 1.4571 (ASTM A182 F316Ti), reactor replacement nozzles — matching existing 1.4571 system, 320 °C, EN 10204 3.1 — 6 pcs.” Quotations normally within 24 hours with price, unit weight and delivery.
What is an ASTM A182 F316Ti long weld neck flange?
An ASTM A182 F316Ti long weld neck flange is a forged titanium-stabilised austenitic stainless steel flange — UNS S31635, W.Nr. 1.4571, the X6CrNiMoTi17-12-2 of European practice — whose neck continues as a long, heavy-walled straight barrel that is itself the nozzle, bevelled at its far end for one closing butt weld made out at the vessel, column or exchanger shell. F316Ti is the third answer to the austenitic weld question: titanium, added at five times the carbon-plus-nitrogen content, claims the carbon before chromium ever can — so the weld zone stays corrosion-safe while the grade keeps full standard-316 strength, 515/205 MPa. Flange ends follow ASME B16.5 in Classes 150 to 2500; the barrel is machined to the ordered length and bore. Supplied solution annealed with records.
How does a long weld neck differ from a standard weld neck flange?
Geometry and mission. A standard weld neck's hub tapers quickly down to the pipe's outside diameter and wall, ending in a weld bevel a few centimetres from the flange face — it is built to butt-weld to pipe and continue as a piping run. A long weld neck keeps a full-section straight barrel for its entire length: no taper to pipe dimensions, wall far heavier than the matching schedule, length made to order. The mission follows the shape — the LWN is not a fitting on a pipe run but a nozzle in its own right, projecting through insulation, vessel walls or exchanger channels, with the butt weld relocated to the shell side where the fabricator wants it. In one certified forging it replaces the weld neck flange, the pipe nipple and one whole circumferential weld.
How does titanium stabilisation work — the third answer to the weld question?
By giving the carbon a better offer. Sensitisation happens because carbon finds chromium in the weld's heat-affected zone, forming the grain-boundary carbides that strip the passive film. The austenitic bench has three answers: remove the carbon (the L grades), embrace it for creep strength (the H grades) — and lock it, which is 316Ti's move. Titanium is a far stronger carbide former than chromium, so with a deliberate addition of at least five times the carbon-plus-nitrogen content, every carbon atom is claimed as harmless titanium carbide long before it can touch the chromium. The weld zone keeps its film, no post-weld treatment is needed — and unlike the L route, no strength is surrendered: the carbon is still there, still an interstitial strengthener, just safely spoken for. The certificate shows the result: full standard-316 numbers on a weld-safe grade.
Why is 316Ti the European classic — the 1.4571 story?
Because the DIN world standardised on stabilisation a generation before low-carbon melting became cheap. When sensitisation was the industry's great weld problem, two solutions competed: starve the carbon (hard to do consistently with mid-century steelmaking) or lock it with titanium (robust with the melting practice of the day). Continental Europe chose the lock: 1.4571 became the default molybdenum stainless of German, Dutch and central-European engineering, written into DIN and later EN piping classes by the thousand, and half a century of chemical plant along the Rhine is flanged in it. The habit outlived its original reason — modern melting makes 316L effortless — but European specifications still name 1.4571 routinely, replacement and expansion projects must match existing metallurgy, and the grade's genuine elevated-temperature edge keeps the choice rational as well as customary. For exporters to European-specified projects, F316Ti is not a curiosity; it is a standing requirement.
What is the chemical composition of ASTM A182 F316Ti?
Carbon ≤0.08%, manganese ≤2.00%, silicon ≤1.00%, phosphorus ≤0.045%, sulphur ≤0.030%, chromium 16.0-18.0%, nickel 10.0-14.0%, molybdenum 2.00-3.00%, and the signature column: titanium at a minimum of five times the combined carbon and nitrogen content, up to 0.70%. The frame is plain 316's — same chromium, nickel and molybdenum — and two details reward attention. The carbon cap stays at the straight grade's 0.08%: stabilisation makes low carbon unnecessary, which is the entire point. And the titanium requirement is a formula, not a range, because the amount needed depends on what it must neutralise — a certificate showing Ti at five times (C+N) is showing the stabilisation arithmetic done and proven. Chemistry is verified per heat, PMI-confirmed with the titanium line read, and travels on the EN 10204 3.1 MTC.
What are the mechanical properties of F316Ti long weld neck flanges?
Solution annealed: tensile strength 515 MPa (75 ksi) minimum, yield strength 205 MPa (30 ksi) minimum, elongation 30% minimum — full standard-316 strength, and that is the stabilised route's quiet advantage over the L route: weld-zone immunity with nothing surrendered on the certificate. Designs that lean on the 205 MPa yield line get it without dual-certification arithmetic, and the B16.5 austenitic group ratings apply per the standard. The austenitic gifts carry over — no ductile-brittle transition, toughness to cryogenic temperatures with impacts documented where required, hardness comfortably low. One honest note for the fine print: the titanium carbides that do the stabilising can slightly reduce polishability against 316L, which is why the hygienic industries lean L — the trade-offs FAQ takes that up.
316Ti or 316L — how do the two weld-safe routes compare?
Both answer sensitisation; they differ at the edges. Strength: 316Ti keeps 515/205 where L-only supply certifies 485/170 — the stabilised grade wins wherever yield is leaned on, without needing dual certification. Elevated temperature: titanium carbides are stable where the L grade's protection is simply absence — hold 316L long enough in the sensitising band and its few remaining carbon atoms can still slowly migrate, while 316Ti's are locked for good; European practice therefore trusts 1.4571 through sustained warm service to ~550°C. Surface and hygiene: the L grade wins — titanium carbide stringers resist electropolishing, so pharma writes 316L. Availability: 316L is the global commodity, 316Ti the European specialty with a lead-time story. The honest summary: for European-specified plant, matching metallurgy decides; for warm chemical duty with strength in the calculation, Ti has the better argument; for hygienic and general work, the world has voted L.
What is F316Ti's elevated-temperature position — and where does F316H take over?
Stabilisation buys stability, not creep allowables — the distinction matters. Through sustained warm-to-hot service the titanium lock never expires, so European practice runs 1.4571 confidently to around 550°C where an unstabilised straight grade would sensitise over the years — intergranular safety through the whole service life, which is what the DIN tradition prized. But ASME code creep design is a different question: elevated-temperature allowable stresses in the creep range belong to the H grades, whose deliberate carbon floor builds the strengthening carbides — 316Ti's locked carbon, by design, cannot. The rule for specifiers: long warm service with corrosion in mind, 316Ti serves and European practice endorses it; code-governed creep design above roughly 525°C, F316H is the grade the tables name. The two answer different questions, and this site keeps both benches.
How is the closing weld on an F316Ti LWN made?
Under the friendly austenitic rules, with the stabilised grade's own filler logic. No preheat beyond dryness, no PWHT, ordinary technique and interpass control. Fillers: matching stabilised consumables where available — European practice pairs 1.4571 with niobium-stabilised fillers, since titanium transfers poorly across an arc — or standard 316L-class fillers, whose low carbon needs no stabilising; both routes are qualified practice and the WPS states which applies. The base metal's heat-affected zone is the stabilised grade's showcase: the titanium lock holds through the weld cycle, so the joint stays intergranular-safe as-welded. Heat tint is removed by pickling or passivation on corrosion-critical work, and the closing weld at the shell inherits the vessel's own qualified procedure. WPS guidance travels with every supply.
How are the barrel length and bore of a LWN specified?
Two numbers that belong on every enquiry. Length: measured overall from the flange face to the weld end — 150 mm (6"), 230 mm (9") and 300 mm (12") are the common stock lengths, and any length machines to order; state it explicitly, because 'long' is not a dimension. Bore: the barrel is drilled and bored to order — most commonly to match the inside diameter of the connecting pipe schedule, sometimes cylindrical special bores for level bridles, instrument standpipes or restriction work; state the schedule or the finished bore in millimetres. Add the weld-end preparation (standard 37.5° bevel unless told otherwise) and the nozzle is fully defined.
Where do F316Ti LWN flanges serve?
Wherever European specifications reach, and wherever warm corrosive service rewards the titanium lock: chemical and petrochemical plant built to DIN/EN piping classes — the Rhine-corridor tradition and its licensees worldwide — replacement and expansion nozzles on existing 1.4571 systems where matching metallurgy is mandatory, warm chloride-bearing process columns and exchangers running years between shutdowns, hot-water and steam-adjacent utilities in the band where unstabilised grades would slowly sensitise, and export fabrications certified against European material lists. The LWN construction serves its usual purpose — nozzle, neck and reinforcement in one forging, one closing weld — and on European-specified vessels it arrives with the EN 10204 documentation culture those projects expect.
When does F316Ti hand off — across the answers or up the ladder?
Across the weld-question answers: hygienic and electropolished work takes 316L, whose carbide-free structure polishes cleaner; code creep design takes F316H, whose carbon is deliberately unlocked; and general low-cost as-welded duty increasingly takes the dual-certified commodity the world stocks. Up the chloride ladder, the familiar walls stand unchanged — stabilisation does nothing for chloride stress corrosion cracking above ~60°C, which remains duplex F51's cure, and the seawater line stays with the super duplex twins at PREN 40. Sideways by geography: where the specification is European, 1.4571 is often simply the named grade and the hand-off question never arises. State the specification tradition, the medium and the temperature — those three place the grade faster than any datasheet comparison.
What sizes and pressure classes do F316Ti LWN flanges come in?
Flange ends follow ASME B16.5 from ½" to 24" NB in Classes 150, 300, 400, 600, 900, 1500 and 2500 — with the full class-by-class LWN dimension charts on this site — and larger diameters forge to order against B16.47 or drawing dimensions. The European-heritage note matters doubly here: EN 1092-1 drilling and PN-designated pressure ratings are machined on the same barrels, and a large share of 1.4571 work arrives specified that way — state whether the project runs ASME classes or EN PN ratings and the flange end follows. The order book concentrates in Classes 150-600 and their PN equivalents, chemical-plant territory, with higher classes to order. State size, class or PN, barrel length and bore together, and our quotation returns price, unit weight and delivery.
What details are needed to get an accurate F316Ti LWN flange quotation?
Seven elements plus commercial terms: (1) size and dimensional standard — ASME B16.5 or EN 1092-1, stated explicitly given the grade's European habitat; (2) pressure class or PN rating; (3) facing — RF (the default), FF or RTJ with ring number; (4) barrel length overall, face to weld end — 150/230/300 mm stock or any stated length; (5) barrel bore — pipe schedule to be matched or finished bore in millimetres, with pattern (standard, heavy barrel, equal barrel) and weld-end prep if non-standard; (6) the grade line — ASTM A182 F316Ti / UNS S31635, or EN 1.4571 where the specification is European — with the service stated (medium, temperature, matching-metallurgy requirements) so the grade is confirmed against 316L across and F316H above; (7) certification — EN 10204 3.1 with solution-anneal records (our standard) or 3.2 witnessed. Add quantity and destination; quotations normally within 24 hours, with the specialty-grade lead time stated honestly.
Who manufactures ASTM A182 F316Ti long weld neck flanges in India?
Tesco Steel & Engineering is an ISO 9001:2015 certified flange manufacturer based in Mumbai, India, producing ASTM A182 F316Ti / EN 1.4571 long weld neck flanges with ASME B16.5 or EN 1092-1 flange ends from ½" to 24" NB (larger to order) in Classes 150-2500 and their PN equivalents, in standard, heavy-barrel and equal-barrel patterns — each forged individually from certified stabilised heats, solution annealed with records retained, machined with the barrel bored to the ordered schedule or drawing, bevelled for the closing weld, PMI-checked with the titanium line read on every piece, and marked with grade, size, schedule and heat number. Supplied with EN 10204 3.1/3.2 certification and stainless WPS guidance covering stabilised and 316L filler routes — alongside the 316/316L/316H bench, the 304 family, the duplex ladder, and the complete long weld neck range. Exported to more than 50 countries.
