Constructing high-reliability fluid transfer networks for FPSOs, offshore platforms, and coastal petrochemical complexes across Southeast Asia demands piping solutions capable of enduring severe chloride pitting, crevice corrosion, and high mechanical fatigue. Standard austenitic grades like 316L often struggle under high salinity and elevated pressure differentials. Delivering on a critical marine infrastructure order in Singapore, Haihao Group has manufactured, non-destructively evaluated, and dispatched a high-specification batch of large and mid-diameter duplex stainless steel seamless pipes.

Engineered to ASME B36.19M and ASME B36.10M standards with butt-weld ends (BWE) per ASME B16.25, this delivery consists exclusively of seamless ASTM A790 UNS S31803 (Duplex 2205) pipework verified with EN 10204 Type 3.2 material certification.

Haihao Group ASTM A790 UNS S31803 seamless pipe ASME B36.19M SCH 40S

Order Technical Breakdown & Pipe Schedule Matrix

To support diverse pressure ratings across process manifolds and utility headers in Singapore, the consignment covers a versatile range of nominal pipe sizes (NPS) and wall thicknesses:

Metallurgical Advantages: ASTM A790 UNS S31803 Duplex Microstructure

Sourcing seamless tubulars through a certified ASTM A790 UNS S31803 seamless pipe supplier guarantees that critical subsea and topside fluid loops maintain extreme yield strength and corrosion immunity throughout their operational lifecycle.

Haihao Group enforced rigid process parameters during hot extrusion, cold finishing, and solution annealing for this Singapore shipment:

Dual-Phase Microstructure Equilibrium: Duplex UNS S31803 combines approximately equal proportions of austenitic and ferritic phases. This dual-phase structure provides nearly double the yield strength of conventional 316L stainless steel, allowing engineers to design thinner pipe walls (such as SCH 10S in 10” and 12” sizes) without compromising pressure integrity.

Chloride Stress Corrosion Resistance: High chromium (21–23%), molybdenum (2.5–3.5%), and nitrogen contents yield a Pitting Resistance Equivalent Number (PREN≥ 34), protecting pipe walls against localized pitting in warm, salty tropical waters.

Seamless Construction Uniformity: Manufactured without longitudinal weld seams, these hot-finished and cold-drawn tubulars eliminate potential heat-affected zone (HAZ) weaknesses, ensuring uniform hoop-stress distribution under high internal pressures.

Strict Quality Inspection, Third-Party Verification & Seaworthy Packaging

To maintain our standing as a trusted ASTM A790 UNS S31803 seamless pipe supplier, every pipe length underwent comprehensive quality gates prior to export:

100% Volumetric Ultrasonic & Eddy Current Testing: All seamless pipes were tested per ASTM A790 and ASME Section V to rule out subsurface laminations, wall thinning, or manufacturing defects.

Bevel Precision per ASME B16.25: End bevels were CNC-machined to 37.5° ± 2.5° with smooth root faces to enable efficient automatic field welding on site in Singapore.

Independent EN 10204 Type 3.2 Certification: Third-party inspection agencies witnessed mechanical tensile, hardness, intergranular corrosion testing, and hydrostatic trials, issuing full EN 10204 3.2 certificates.

Protective Export Handling: Pipe ends were fitted with heavy-duty plastic caps, while pipe bodies were bundled with soft slings and wrapped in moisture-resistant sheeting for safe ocean freight.

Partnering with an experienced ASTM A790 UNS S31803 seamless pipe supplier eliminates project delay risks, ensures seamless field welding, and lowers total cost of ownership in marine environments.

Partner with Haihao Group for Singapore Offshore Assets

Require certified duplex stainless steel seamless pipes, ASME B36.19M tubulars, or custom pipe spools for your energy and marine projects in Singapore and Southeast Asia? Work with a reliable ASTM A790 UNS S31803 seamless pipe supplier. Contact the Haihao Group commercial sales team today for fast technical consultations and competitive pricing.