Critical Pressure Connections: Haihao Group Dispatches Heavy-Duty Flanges and Blinds to Singapore
Connecting high-pressure topside manifolds, fuel skids, and subsea tie-in loops in Singapore’s marine construction yards demands flanged connections with unyielding mechanical strength and zero-leakage sealing interfaces. Standard lightweight flanges often fail under the severe cyclic stresses, thermal expansion, and hydrostatic testing surges common in offshore installations. Fulfilling a comprehensive technical contract for an offshore energy project in Singapore, Haihao Group has manufactured, non-destructively evaluated, and shipped a multi-class consignment of heavy-wall forged steel flanges and positive isolation blinds.
Engineered strictly to ASME B16.5 and ASME B16.48 specifications, this export order combines normalized carbon steel forgings (ASTM A105N), high-yield forged steel (ASTM A694 Grade F60), and pressure vessel steel plate (ASTM A516 Grade 70).
ASME B16.5 ASTM A105N Class 2500 RTJ weld neck flange and ASTM A516 Gr 70 paddle spacer manufactured by Haihao Group
Consignment Overview & Technical Parameter Schedule
To satisfy both ultra-high pressure process lines and standard utility isolation across the Singapore shipyard, the consignment includes four primary product groupings:
| Component Category | Size Range | Pressure Rating | Facing / Wall Schedule | Material Grade | Manufacturing Standard |
| High-Pressure WN Flange | 1″ to 2″ | Class 1500 / 2500 | Ring Type Joint (RTJ), XXS | ASTM A105N / A694 F60 | ASME B16.5 |
| Standard WN & SW Flange | 1/2” to 10” | Class 150 / 300 / 900 | Raised Face (RF) / FF, SCH 30 to 160 | ASTM A105N Normalized | ANSI / ASME B16.5 |
| Specialty Drilled Blind | 2” x 3/8” | Class 600 | Raised Face (RF) Tapped | ASTM A105N Normalized | ASME B16.5 |
| Positive Line Isolation Blind | 1” to 12” | Class 150 / 300 / 1500 | Flat Face (FF) & RTJ | ASTM A516 Grade 70 | ASME B16.48 |
Metallurgical Defense & Precision Sealing Surface Machining
Sourcing heavy-wall pressure components through a certified ASME B16.5 ASTM A105N flange manufacturer ensures that critical piping joints maintain structural integrity without flange face deflection or gasket blowout under extreme pressure surges.
Haihao Group enforced tight quality controls across all forging, heat treatment, and machining operations:
High-Yield Forgings for Extreme Ratings: For Class 2500 heavy-wall weld neck flanges, high-yield ASTM A694 Grade F60 steel forgings were selected alongside normalized ASTM A105N. Normalizing heat treatment refined the grain structure, eliminating internal stresses to maintain high impact energy absorption in marine environments.
Metallic RTJ Sealing Precision: Class 1500 and Class 2500 weld neck flanges and 8” Class 1500 paddle blanks feature precision CNC-machined Ring Type Joint (RTJ) grooves. The metal-to-metal wedge seal ensures absolute pressure containment under severe cyclic loading.
Positive Separation with ASME B16.48 Blinds: Flame-cut from ASTM A516 Grade 70 boiler plate, the spectacle blinds, paddle blanks, and paddle spacers provide foolproof physical line separation during maintenance. Flat Face (FF) gasket surfaces were finish-turned with spiral serrations (125–250μin.Ra) for leak-free gasket compression.
Custom Tapped Instrument Connections: The 2” x 3/8” Class 600 blind flange features a precision-drilled, NPT-tapped center bore engineered specifically for flatolet instrumentation take-offs.
Exhaustive Inspection, Surface Preservation & Ocean Freight Packaging
To uphold our reputation as a trusted ASME B16.5 ASTM A105N flange manufacturer, every item in this consignment passed rigorous multi-stage quality gates prior to export:
100% Volumetric & Surface NDE: High-pressure Class 1500 and Class 2500 RTJ flanges underwent Magnetic Particle Inspection (MPI) and Ultrasonic Testing (UT) per ASME Section V to guarantee zero internal forging seams or inclusions.
Dimensional Tolerance Verification: Sealing face heights, RTJ groove dimensions, bolt hole pitch circles, and heavy wall schedules (Schedule XXS, 160) were verified against ASME B16.5 tolerances using calibrated digital gauges.
Coating & Flange Face Protection: Machined sealing faces and RTJ grooves were coated with heavy-duty rust-preventative varnish and fitted with custom wooden flange caps to prevent face damage during ocean transport to Singapore.
Complete Traceability Dossier: Shipped with EN 10204 3.1 Mill Test Certificates detailing chemical heat logs, mechanical tensile/hardness data, normalizing charts, and NDE test reports.
Partnering with an experienced ASME B16.5 ASTM A105N flange manufacturer eliminates field alignment issues, prevents pressure leakage, and lowers lifecycle risk for complex offshore assets.
Partner with Haihao Group for Singapore Offshore Infrastructure
Searching for certified Class 1500/2500 RTJ weld neck flanges, ASME B16.48 spectacle blinds, or custom A694 F60 forgings for your refinery or offshore projects in Singapore? Work with a reliable ASME B16.5 ASTM A105N flange manufacturer. Contact the Haihao Group commercial sales engineering team today for rapid technical consultations and competitive quotes.