Explore our high-integrity forged stainless steel flanges engineered for high-pressure oil, gas, chemical, and industrial pipeline networks globally.
Founded in 1992 in the Zhuangli Industrial Zone of Dingxiang County, Shanxi—recognized globally as the premier “Hometown of Forging in China”—Shanxi Yuxin Casting & Forging Co., Ltd. operates a vertically integrated manufacturing ecosystem spanning 10,000+ metric tons of annual forged flange output.
Unlike asset-light trading intermediaries, YUXIN controls every physical transformation step: electric-induction ingot heating, hydraulic closed-die and ring-rolling forging, automated solution annealing heat treatment, multi-axis CNC face machining, high-precision bolt drilling, and 100% NDT inspection.
In global piping design, flange dimensions must precisely interface with pressure vessel ratings, pipe schedules, and gasket sealing dynamics. China's leading manufacturers synthesize Western (ASME/EN) and Eastern (JIS/GB) standard frameworks.
| Standard Framework | Nominal Size Range | Pressure Class / PN Rating | Facing Types | Primary Stainless Alloys | Dimensional Tolerance Standard |
|---|---|---|---|---|---|
| ASME B16.5 | NPS ½" to 24" (DN15 - DN600) | Class 150, 300, 600, 900, 1500, 2500 | RF (Raised Face), RTJ (Ring Type Joint), FF, M&F | ASTM A182 F304/304L, F316/316L, F321, F347, F51 | ASME B16.5 Section 7 / MSS SP-44 |
| ASME B16.47 (Ser. A / B) | NPS 26" to 60" (DN650 - DN1500) | Class 75, 150, 300, 600, 900 | Raised Face (RF), Ring Type Joint (RTJ) | ASTM A182 F304L, F316L, Duplex 2205, 2507 | ASME B16.47 Tolerances |
| EN 1092-1 (European) | DN10 to DN4000 | PN 2.5, 6, 10, 16, 25, 40, 63, 100 | Type A (Flat), Type B (Raised), Type C/D (Tongue/Groove) | 1.4301 (304), 1.4404 (316L), 1.4541 (321), 1.4462 | EN 1092-1 Annex A & B |
| DIN Standards (Legacy) | DN10 to DN3000 | PN 6 to PN 160 | Form C, Form D, Form E, Form F | X5CrNi18-10, X2CrNiMo17-12-2 | DIN 2501 / DIN 2519 |
| JIS B2220 (Japanese) | 10A to 1500A | 5K, 10K, 16K, 20K, 30K | RF, FF, Male & Female | SUS304, SUS316, SUS316L, SUS316Ti | JIS B2220 Precision Limits |
Key parameters for stainless steel flange sourcing include Outer Diameter (OD), Bolt Circle Diameter (BCD), Bolt Hole Count & Diameter, Flange Thickness (C/T), Hub Length (H), and Bore Diameter matching Schedule 10S, 40S, 80S, or XXS pipe walls.
Critical Inspection PointEngineered flange faces feature spiral serrated finishes (125–250 µin / 3.2–6.3 µm Ra per ASME B16.5) for compressed asbestos-free or spiral wound gaskets, and smooth finish (< 63 µin Ra) for soft metallic gaskets.
Sealing IntegrityStainless steel flanges exhibit dynamic allowable stresses across thermal gradients. Austenitic grades (304L/316L) maintain structural integrity from sub-zero cryogenic temperatures (-196°C) up to 815°C elevated service.
ASME B16.5 Table 2-2.2Selecting the ideal stainless steel grade prevents catastrophic pitting, crevice corrosion, and chloride stress-corrosion cracking (SCC) in aggressive processing conditions.
The global standard for general industrial piping, municipal water treatment, and food/beverage lines. Dual-certified 304/304L maintains low carbon content (C ≤ 0.030%) to eliminate carbide precipitation during field welding.
PREN Value: ~18 - 20 | Temp Range: -196°C to 800°C
Formulated with 2.0–3.0% Molybdenum addition, 316L provides enhanced resistance to chloride pitting and chemical acids. Essential for marine infrastructure, offshore platforms, and pharmaceutical processing.
PREN Value: ~23 - 25 | Temp Range: -196°C to 850°C
Dual-phase ferritic-austenitic microstructures yielding twice the mechanical yield strength of standard austenitic alloys, alongside exceptional resistance to stress corrosion cracking in high-salinity marine and oilfield sour services.
PREN Value: >32 (Duplex 2205) / >42 (Super Duplex 2507)
In chemical plant design, alloy corrosion performance is mathematically evaluated using the industry formula:
PREN = %Cr + (3.3 × %Mo) + (16 × %N)
YUXIN provides full ladle and product chemical spectroscopy with each shipment, confirming exact PREN compliance for severe environmental service.
China accounts for over 60% of the world's total forged steel flange output. Understanding the structural advantages of Chinese forging clusters enables EPC procurement heads to optimize total cost of ownership (TCO).
Proximity to premier domestic stainless steel raw billet mills (Tsingshan, Baosteel, TISCO) ensures immediate access to certified round bars, reducing billet lead times to under 48 hours.
Modern Chinese forging plants employ multi-axis CNC turning centers, automatic high-speed drilling machines, and digital measuring arms for tight dimensional tolerances (±0.5 mm hub, ±0.2 mm facing).
100% positive material identification (PMI), ultrasonic testing (UT per ASTM A388), liquid penetrant testing (PT per ASTM E165), and hydro-testing guarantee zero-defect export shipments.
Our flanges serve critical high-pressure and corrosive environments across global engineering projects.
FPSO vessel topsides, subsea manifold trees, and mud lines require Class 900 to Class 2500 RTJ Weld Neck flanges in ASTM A182 F51 / F53 duplex alloys to survive high-pressure sour gas (H2S) environments.
NACE MR0175 CompliantRefinery hydrocrackers, nitric acid distillation towers, and PTA plants demand low-carbon 316L, 317L, and 904L Slip-On and Blind flanges to withstand high-temperature acid solutions without localized grain decay.
Corrosion ResistantLiquefied natural gas re-gasification terminals and ISO tank containers utilize ASTM A182 F304L/F316L flanges evaluated down to -196°C via Charpy V-notch impact testing to ensure microstructural ductility.
Cryogenic TestedHigh-purity bio-pharmaceutical reactors and ultra-pure water (UPW) loops mandate mirror-polished 316L sanitary flanges (Ra < 0.4 µm) with zero dead-leg geometry to prevent bacterial accumulation.
High Surface FinishDriven by decarbonization targets, digital twin integration, and demanding subsea exploration, the global pipe fitting industry is undergoing a structural technological transition.
The push for green hydrogen networks demands ultra-dense forging microstructures to prevent hydrogen embrittlement. Standard 316L stainless steel flanges are undergoing specialized electropolishing and tight grain-size control (ASTM E112) for high-pressure gaseous hydrogen storage.
Global EPC contractors (e.g., Technip, Bechtel, Petrofac) increasingly require QR-code laser engraving directly onto flange rims. Scanning the code instantly surfaces the digital EN 10204 3.1 Mill Test Certificate, heat treatment curves, and NDT inspection reports.
To reduce overall project costs, manufacturers are expanding production of carbon steel flanges weld-clad with Inconel 625 or 316L stainless steel sealing faces—delivering superior localized corrosion resistance at a fraction of solid high-alloy costs.
Review our extended product catalogue, featuring specialized blind flanges, socket weld connections, stub ends, and heat exchanger tube sheets.
To avoid project delays, dimensional mismatches, or material non-compliance, international procurement officers should incorporate this rigorous step-by-step verification protocol.
Specify exact dual-grade requirements (e.g., 316/316L) and require full solution annealing per ASTM A182/A182M (heat to 1040°C minimum followed by rapid water quenching below 400°C) to prevent sensitization.
Confirm pipe wall schedule (e.g., Sch 40S, Sch 80S, Sch 160) for Weld Neck flanges to ensure smooth internal flow transitions and eliminate turbulence-induced erosion corrosion at weld bevels.
Mandate EN 10204 3.1 certification containing physical tension, yield, elongation, and impact values, alongside chemical ladle analysis. Third-party inspection witness (SGS, TÜV, BV, DNV) can be arranged prior to seaworthy packaging.
Direct responses from YUXIN’s engineering desk addressing critical flange design, material selection, standards alignment, and order execution queries.
Need specialized stainless steel flange sizes, custom drawing-based forgings, or full project BOM pricing? Our engineering team responds with complete manufacturing proposals within 24 hours.
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