Subsea Pipe Fittings Saudi Arabia — Super Duplex 2507 and Duplex 2205 — NACE MR0175

Gulf Union Ozone Trading Co. (CR 4030570569) supplies ISO 9001:2015 certified wrought duplex and super duplex stainless steel butt-weld pipe fittings for Saudi Arabia offshore and Red Sea subsea pipeline projects. ASTM A815, ASME B16.9. PREN ≥42 (super duplex 2507). EN 10204 3.1 MTCs with actual chemical analysis, PREN calculation, and hardness values.

GradesSuper Duplex 2507 · Duplex 2205
UNS NumbersS32750 · S31803 / S32205
StandardASTM A815 · ASME B16.9
PREN≥42 (2507) · ≥35 (2205)
Sour ServiceNACE MR0175 / ISO 15156
MTCEN 10204 3.1 with actual PREN
Subsea Grade Selection — 2507 vs 2205

Super Duplex 2507 vs Duplex 2205 — Which Grade for Saudi Arabia Offshore Service?

Duplex and super duplex stainless steels are the materials of choice for subsea and offshore pipelines in chloride-rich environments such as the Red Sea and Arabian Gulf. Their dual ferritic-austenitic microstructure delivers higher strength than austenitic grades (316L, 304L) and better corrosion resistance than carbon steel — without the high cost of nickel alloys (Inconel 625, Alloy 825).

The critical parameter for seawater corrosion resistance is the PREN (Pitting Resistance Equivalent Number): PREN = %Cr + 3.3(%Mo) + 16(%N). A PREN ≥40 is generally required for submerged seawater service at temperatures above 30°C. Super duplex 2507 achieves PREN ≥42 by design; duplex 2205 achieves PREN ≥35 — suitable for less aggressive offshore or process piping in seawater-cooled systems.

Super Duplex 2507 vs Duplex 2205 — Key Properties
Property Super Duplex 2507 Duplex 2205
UNS NumberS32750S31803 / S32205
ASTM A815 GradeWPS32750WPS31803 / WPS32205
Cr / Mo / N (%)25 / 4 / 0.2822 / 3 / 0.17
PREN (min)≥42≥35
SMYS (MPa)550 (80 ksi)450 (65 ksi)
SMTS (MPa)800 (116 ksi)620 (90 ksi)
Max hardness36 HRC (NACE)36 HRC (NACE)
Seawater suitabilityFull submergedOffshore/topside
Max temperature (seawater)~50°C~35°C
When to Specify Super Duplex 2507 vs Duplex 2205

Super Duplex 2507 (PREN ≥42)

  • Full submerged seawater service >30°C
  • Red Sea offshore pipeline risers and flowlines
  • Chloride stress corrosion cracking (Cl-SCC) risk above 60°C
  • Sour service with chlorides (combined H₂S + Cl⁻)

Duplex 2205 (PREN ≥35)

  • Offshore topside piping and equipment
  • Seawater cooling systems below 35°C
  • Sour gas service without chlorides
  • Cost-sensitive offshore projects where PREN ≥40 not required
EN 10204 3.1 MTC — What Must Be Reported for Subsea
  • Actual chemical analysis (heat-specific, all elements)
  • PREN calculated from actual Cr, Mo, N values
  • Hardness values (HRC or HV10 — must meet NACE ≤36 HRC)
  • Tensile and yield strength, elongation
  • Ferrite content (volumetric) — target 35–65%
  • Heat number and production date traceable to fitting
  • Manufacturer's 3.1 inspector signature and stamp
Subsea Fitting Stock Range

ASTM A815 Butt-Weld Fittings — Duplex and Super Duplex in Stock

Fitting Type Standard Grade — Super Duplex Grade — Duplex Size Range
90° LR Elbow ASME B16.9 A815 WPS32750 A815 WPS31803 NPS ½″–12″
90° SR Elbow ASME B16.9 A815 WPS32750 A815 WPS31803 NPS 1″–12″
45° Elbow ASME B16.9 A815 WPS32750 A815 WPS31803 NPS ½″–12″
Equal Tee ASME B16.9 A815 WPS32750 A815 WPS31803 NPS ½″–12″
Reducing Tee ASME B16.9 A815 WPS32750 A815 WPS31803 NPS 1″–12″
Concentric Reducer ASME B16.9 A815 WPS32750 A815 WPS31803 NPS ½″–12″
Eccentric Reducer ASME B16.9 A815 WPS32750 A815 WPS31803 NPS ½″–12″
End Cap ASME B16.9 A815 WPS32750 A815 WPS31803 NPS ½″–12″

Sizes above NPS 12″ and wall thicknesses above Sch 80S available on order. WPS32760 (Zeron 100, PREN ≥41) available on request for most aggressive subsea conditions. All fittings solution-annealed and pickled per ASTM A815.

Flanges for Subsea Service

For subsea pipeline flanges, Gulf Union Ozone also supplies ASTM A182 F53 (super duplex 2507 forged flanges, UNS S32750) and ASTM A182 F51 (duplex 2205, UNS S31803) weld-neck and blind flanges per ASME B16.5. Weld neck flanges matched to pipe schedule for full-bore bore-to-bore compatibility. View A182 flanges →

FAQ

Subsea Fittings — Questions Answered

What grade of stainless steel is used for subsea pipe fittings in Saudi Arabia?

Super duplex 2507 (UNS S32750, ASTM A815 WPS32750) is the standard grade for fully submerged seawater service — PREN ≥42, SMYS 550 MPa. For offshore topside and less aggressive applications, duplex 2205 (UNS S31803/S32205, ASTM A815 WPS31803) with PREN ≥35 is suitable. Both grades are NACE MR0175 compatible at hardness ≤36 HRC.

What ASTM standard covers subsea butt-weld fittings?

Duplex and super duplex butt-weld fittings are covered by ASTM A815 (Wrought Ferritic, Ferritic/Austenitic, and Martensitic Stainless Steel Piping Fittings). Dimensions follow ASME B16.9. Key grades: WPS32750 (super duplex 2507), WPS31803 (duplex 2205), WPS32205 (duplex 2205 modified). WPS32760 (Zeron 100) available on order for the most aggressive subsea conditions.

What is the PREN for super duplex 2507 and why does it matter for subsea service?

PREN = %Cr + 3.3(%Mo) + 16(%N). Super duplex 2507: PREN ≥42 minimum. Duplex 2205: PREN ≥35. For full submerged seawater service above 30°C in the Red Sea or Arabian Gulf, PREN ≥40 is generally required to resist pitting corrosion. Gulf Union Ozone supplies super duplex 2507 fittings with actual PREN values calculated from the heat's actual chemical analysis and reported in the EN 10204 3.1 MTC.

Do you supply super duplex fittings for Red Sea offshore projects in Saudi Arabia?

Yes. Gulf Union Ozone supplies super duplex 2507 (A815 WPS32750) and duplex 2205 (WPS31803) butt-weld fittings for Red Sea offshore and shallow-water subsea projects. EN 10204 3.1 MTCs include actual chemical analysis, PREN calculation, hardness (HRC), ferrite content, and where required, NACE TM0177 SSC test results. Contact us via WhatsApp or email with your project MTO for a quotation.
Related Products and Guides
Duplex 2205 and Super Duplex 2507 → ASTM A403 SS Fittings (WP304L/WP316L) → ASTM A182 F51/F53 Flanges → NACE MR0175 Sour Service Materials → Gas Pipeline Supplier (API 5L) → All Pipe Fittings →
ASTM A815 · ASME B16.9 · PREN ≥42 · NACE MR0175 · EN 10204 3.1 · ISO 9001:2015

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In Summary

Gulf Union Ozone Trading Co. supplies Subsea Pipe Fittings to industrial customers across Saudi Arabia with delivery from our Jeddah warehouse — all products ship with original Mill Test Certificates and Certificates of Conformance.

In Summary

Subsea Pipe Fittings from Gulf Union Ozone serves Saudi Aramco SAEP-347 projects, SABIC, SADARA, SEC utilities, NEOM mega-projects, and industrial facilities across the Kingdom — our inventory covers the most common material grades and pressure ratings.

In Summary

Gulf Union Ozone stocks a wide range of Subsea Pipe Fittings including various grades, sizes, and pressure classes — contact us on WhatsApp for immediate availability confirmation and a quotation with full MTC documentation.

In Summary

For urgent Subsea Pipe Fittings procurement in Saudi Arabia, WhatsApp +966 55 098 8062 — our procurement team confirms stock availability within the hour and provides competitive quotations with full compliance documentation for Aramco, SABIC, SEC, and government projects.