ASTM A182 F53 Slip On Flanges — Super Duplex 2507 Manufacturer
Tesco Steel & Engineering forges ASTM A182 F53 slip on flanges — super duplex 2507 (UNS S32750), the 25Cr-7Ni-4Mo-N grade whose PREN of 40+ and 550 MPa minimum yield survive hot seawater, firewater ring mains and the harshest offshore chloride duty — to ASME B16.5 Class 150–2500 from ½″ to 24″ NB, larger patterns to order. The step above duplex 2205 (F51) when water chemistry and temperature demand it, supplied solution annealed, faced SORF (flat face or RTJ where specified), with sister grade F55 (S32760) from the same forge. NACE MR0175 supply on request; every lot with EN 10204 3.1/3.2 MTC. ISO 9001:2015, made in Mumbai, India — exported to 50+ countries.
ASTM A182 F53 Super Duplex Slip On Flange — Raised Face (SORF)
What is an ASTM A182 F53 Slip On Flange?
F53 = super duplex 2507, the hot-seawater grade.ASTM A182 F53 (UNS S32750) pushes the duplex recipe to 25Cr-7Ni-4Mo-N for a PREN above 40 — pitting resistance that holds in warm, chlorinated and stagnant seawater where 2205 runs out — with 800/550 MPa strength, about triple the yield of 316L. As a slip-on, it installs with two fillet welds using ER2594 filler under tight heat-input control — no preheat, no PWHT.
Also searched as: super duplex slip on flange, 2507 slip on flange, S32750 slip on flange, SAF 2507 flange, F53 SORF flange, SA182 F53 slip on flange, 1.4410 slip on flange — all refer to the product on this page.
Super duplex with Cu+W — severe seawater & sour duty
PREN (Pitting Resistance Equivalent Number = %Cr + 3.3×%Mo + 16×%N) ranks chloride pitting resistance — and the 40 threshold is what defines "super" duplex. The family ladder is climbed by water chemistry and temperature, not pressure.
ASTM A182 F53 (UNS S32750) Chemical Composition
C
Mn
Si
P
S
Cr
Ni
Mo
N
Cu
0.030 max
1.20 max
0.80 max
0.035 max
0.020 max
24.0-26.0
6.0-8.0
3.0-5.0
0.24-0.32
0.50 max
Values in weight % per ASTM A182 for UNS S32750. Note the nitrogen is a controlled range (0.24-0.32%), not just a cap — it is a load-bearing element, driving both the PREN above 40 and the strength. Against 2205 this is roughly +3% chromium, +1% molybdenum and half again the nitrogen.
ASTM A182 F53 Mechanical Properties
Tensile Strength, MPa (ksi)
Yield Strength, Min, MPa (ksi)
Elongation % min (2")
Hardness, HB max
800 (116) min
550 (80) min
15
310
Roughly triple the yield of 316L and a clear step above 2205's 450 MPa — strength that lets weight-critical offshore systems run remarkably thin walls. Supplied solution annealed; values demonstrated per heat on the EN 10204 certificate, hardness verified for NACE lots.
A182 F53 Slip On Flange Specifications
ASTM A182 F53 Slip On Flanges are available in the following specifications:
Material
ASTM A182 F53 / ASME SA182 F53 (UNS S32750, Super Duplex 2507 / SAF 2507)
Size
1/2"NB to 24"NB per ASME B16.5; larger patterns and EN 1092-1 super duplex flanges to order
Class
150#, 300#, 400#, 600#, 900#, 1500#, 2500#
Facing
Raised Face (SORF) — default; Flat Face or RTJ where the piping class specifies
Heat Treatment
Solution annealed per ASTM A182, thermal record retained
Service
Hot seawater, firewater, brine & sour duty — typically -50 °C to +250 °C per project specifications
Installation
Two fillet welds (hub + bore), pipe set back 1/8"; ER2594 filler, tight heat-input control, no preheat, no PWHT
Sour Service
NACE MR0175 / ISO 15156 listed material family — supplied with hardness verification within the standard's limits
Certification
EN 10204 3.1 (standard) / 3.2 witnessed; G48 corrosion & ferrite testing where specified
Equivalent Grades of ASTM A182 F53
Standard
ASME
UNS
Werkstoff Nr.
EN
Common Name
ASTM A182 F53
SA182 F53
S32750
1.4410
X2CrNiMoN25-7-4
Super Duplex 2507 / SAF 2507
System partners: ASTM A790 super duplex pipe and A815 fittings in the same UNS number. Certificates always state the actual grade forged. The competing super duplex F55 / S32760 (Zeron 100), with added copper and tungsten, is forged here too.
Why A182 F53 Slip Ons Are Specified
PREN 40+ Holds in Hot Seawater
The critical pitting temperature sits above real service conditions — warm, chlorinated, even stagnant seawater that would pit 2205 eventually and 316L quickly.
The Firewater Standard
Ring mains sit full of still, chlorinated seawater for years — the exact condition super duplex was adopted to survive on offshore topsides worldwide.
Triple the Yield of 316L
800/550 MPa lets weight-critical platforms run thin-wall systems — the strength pays back part of the alloy premium in steel not bought.
Sour-Service Listed
Super duplex is a NACE MR0175 / ISO 15156 listed family — produced fluids and injection systems within the code's limits, hardness verified.
Forging — cut billet of certified A182 F53 heat is hot-forged into the flange blank, keeping full heat traceability from raw material to despatch.
2
Solution annealing — heated and rapidly quenched per ASTM A182 to restore the balanced austenite-ferrite structure and dissolve sigma phase — the critical step at 25% chromium; furnace record retained.
3
Machining — hub, faces and bolt holes to ASME B16.5; the bore machined slightly over pipe OD per the slip-on tolerance.
4
Facing & finish — SORF raised face with serrated stock finish, flat face or RTJ groove; pickled and passivated on request.
5
Testing & marking — mechanical, chemical and hardness verification against the heat; ASTM G48 corrosion and ferrite testing where the order specifies; then permanent marking of grade, size, class and heat number.
6
Certification & packing — EN 10204 3.1 MTC (3.2 witnessed on request), export-packed as pictured on this page.
Where A182 F53 Slip On Flanges Are Used
The harshest chloride services: offshore seawater cooling and injection systems, firewater ring mains, subsea and topside process piping, high-pressure desalination (SWRO) sections, hot brine and chlorinated water circuits, scrubber and FGD duty, and chemical tanker systems where even 2205 runs out. Our super duplex production below:
F53 Super Duplex Flanges — Packed for DispatchF53 Super Duplex — Mirror-Polished Bore DetailA182 F53 Super Duplex Flange — Machined & Marked
A182 F53 Slip On Flange Dimensions
F53 slip-on dimensions follow the ASME B16.5 slip-on tables — identical for every material. Full charts by class:
Example: “Slip On Flange, 4″ NB, ASME B16.5 Class 300, RF, ASTM A182 F53 (S32750), EN 10204 3.1 — 20 pcs.” Quotations normally within 24 hours with price, unit weight and delivery.
ASTM A182 F53 Slip On Flanges — Frequently Asked Questions
What is an ASTM A182 F53 slip on flange?
It is a slip-on flange forged from ASTM A182 F53 — super duplex stainless steel 2507 (UNS S32750) — dimensioned to ASME B16.5. The flange slides over the pipe end and is secured with two fillet welds, and the 25Cr-7Ni-4Mo-N chemistry carries a pitting resistance number (PREN) above 40 with a 550 MPa minimum yield — the combination that survives hot seawater, firewater ring mains and the harshest offshore chloride service where standard duplex 2205 runs out.
What is super duplex stainless steel?
A duplex stainless steel — half austenite, half ferrite — pushed to a pitting resistance equivalent number (PREN) of 40 or more by raising chromium to about 25%, molybdenum toward 4% and nitrogen toward 0.3%. It keeps everything that makes duplex attractive — high strength, chloride SCC resistance, moderate nickel — and extends the corrosion envelope to hot, aggressive chloride waters. The price is faster sigma-phase kinetics, so welding and heat treatment demand tighter control than standard duplex.
What is the chemical composition of ASTM A182 F53?
Per ASTM A182 for UNS S32750: carbon 0.030% max, manganese 1.20% max, silicon 0.80% max, phosphorus 0.035% max, sulphur 0.020% max, chromium 24.0-26.0%, nickel 6.0-8.0%, molybdenum 3.0-5.0%, nitrogen 0.24-0.32% and copper 0.50% max. Note that nitrogen is a controlled range, not just a cap — it is a load-bearing element here, driving both the PREN above 40 and the strength.
What are the mechanical properties of A182 F53 slip on flanges?
Per ASTM A182: tensile strength 800 MPa (116 ksi) minimum, yield strength 550 MPa (80 ksi) minimum, elongation 15% minimum in 2", and hardness 310 HB maximum. That is roughly three times the yield of 316L and a step above duplex 2205's 450 MPa — strength that lets super duplex systems run remarkably thin walls for their pressure. Values are demonstrated per heat on the EN 10204 certificate.
When is F53 chosen over duplex F51?
When the chloride duty gets hotter or harsher than 2205's PREN of ~34 can hold. The classic triggers: seawater above roughly ambient temperature, stagnant or chlorinated seawater (firewater ring mains that sit full and still), high-chloride hot brines, and crevice-prone geometries. F53's PREN of 40+ moves the critical pitting temperature decisively upward. Where 2205 survives, it remains the more economical choice — water chemistry and temperature make the decision.
What is the difference between F53 (S32750) and F55 (S32760)?
Two competing super duplex recipes with the same mission. F53 / 2507 relies on chromium, molybdenum and nitrogen alone; F55 / Zeron 100 (S32760) adds deliberate copper and tungsten for extra crevice and acid resistance. Both carry PREN ≥ 40, near-identical strength and overlapping applications — projects typically standardise on one, often by operator heritage. We forge both; specify whichever your piping class names and the certificate follows.
What temperature range can F53 super duplex slip on flanges handle?
Roughly -50 °C to +250 °C in common specification practice — the same deliberately narrow window as all duplex grades. The higher chromium and molybdenum that buy the corrosion resistance also accelerate embrittling phases: 475 °C embrittlement of the ferrite and sigma-phase precipitation at 700-900 °C form faster in super duplex than in 2205, so the temperature cap is enforced, not advisory. Inside the window, nothing in the price class touches it for hot chloride duty.
Why is super duplex the standard for seawater and firewater systems?
Because its critical pitting and crevice temperatures sit above real seawater service conditions. Warm, chlorinated or stagnant seawater — exactly what a firewater ring main holds — initiates pitting in 316L quickly and in 2205 eventually; PREN 40+ super duplex holds its passive film through it. Add 550 MPa yield for thin-wall, weight-critical offshore topsides, and F53 became the default material of seawater cooling, injection and firewater flanges.
How is an A182 F53 slip on flange welded to pipe?
With two fillet welds — hub outside, bore inside, pipe set back 1/8" (3 mm) — using over-alloyed ER2594 filler and tightly controlled heat input, typically 0.5-1.5 kJ/mm with interpass below about 100-150 °C. The window is tighter than standard duplex because sigma phase forms faster at 25% chromium. No preheat and no PWHT — anything other than a full solution anneal harms super duplex. Qualified duplex welders and ferrite checks are normal practice.
What is the equivalent of ASTM A182 F53 in other standards?
ASME SA182 F53 is the boiler-code twin; UNS S32750 the designation; EN X2CrNiMoN25-7-4 (Werkstoff 1.4410) the European equivalent — all describing super duplex 2507 (also marketed as SAF 2507). System partners specified alongside it: ASTM A790 super duplex pipe and A815 fittings in the same UNS number. Certificates always state the actual grade forged.
Is A182 F53 suitable for sour service under NACE MR0175?
Yes — super duplex is a listed material family in NACE MR0175 / ISO 15156, used for sour produced fluids and injection systems subject to the standard's grade-specific limits on hardness, H2S partial pressure, chloride level and temperature. Solution-annealed forgings with verified hardness fit within those limits. State the NACE requirement and the service conditions on the enquiry, and the flanges ship documented accordingly.
When is super duplex NOT the right choice?
Above the duplex temperature ceiling, in benign waters, and in hot non-chloride process duty. Past ~250-300 °C the embrittling phases rule out all duplex grades regardless of corrosion needs — hot process lines belong to austenitic stainless or alloy steel. In mild chloride service, 2205 or even 316L does the job for far less money. And where the enemy is reducing acids rather than chlorides, nickel alloys outperform. Super duplex earns its premium specifically in hot, aggressive chloride water.
What sizes and classes are A182 F53 slip on flanges available in?
From ½" to 24" NB per ASME B16.5 in Classes 150 through 2500, with larger patterns and EN 1092-1 super duplex flanges forged to order. Super duplex is strictly project material, so flanges are forged against the order — standard sizes normally dispatch within a few weeks with EN 10204 3.1 certification. State the required delivery on the enquiry and we confirm the schedule with the quotation.
What details are needed to get an accurate A182 F53 slip on flange quotation?
Five elements plus commercial terms: (1) size and standard — e.g. 4" NB ASME B16.5; (2) pressure class — 150 through 2500; (3) facing — SORF (raised face) default, flat face or RTJ where specified; (4) grade — ASTM A182 F53 (S32750), NACE MR0175 where sour, plus any corrosion or ferrite testing the project specifies; (5) certification — EN 10204 3.1 or 3.2. No pipe schedule is needed for the slip-on bore. Add the quantity and destination and we return price, weight and delivery.
Who manufactures ASTM A182 F53 slip on flanges in India?
Tesco Steel & Engineering is an ISO 9001:2015 certified flange manufacturer based in Mumbai, India, forging ASTM A182 F53 super duplex 2507 slip on flanges from ½" to 24" NB per ASME B16.5 — alongside F55 super duplex and the F51/F60 duplex grades — in solution-annealed condition with full heat traceability and EN 10204 3.1/3.2 certification on every lot. Flanges are marked with grade, size, class and heat number and export to more than 50 countries.
