Haihao Group Supplies ASME B16.47 Series A Blind Flanges with DNV Approval to Singapore
Haihao Group has successfully completed the production and shipment of ASME B16.47 Series A blind flanges for a client in Singapore. The flanges, sized 48″ 150# RF, are manufactured from ASTM A105 carbon steel and supplied with EN 10204 3.1 Mill Test Certificates approved by DNV classification society.
These large-diameter blind flanges are engineered for high reliability in marine and offshore piping systems, meeting both pressure integrity and corrosion resistance requirements.

DNV-approved ASME B16.47 Series A 48-inch ASTM A105 blind flanges ready for export to Singapore – Haihao Group
Product Overview
| Product | Size | Pressure Rating | Material | Standard | 
|---|---|---|---|---|
| Blind Flange RF | 48″ | 150# | ASTM A105 | ASME B16.47 Series A | 
Each ASTM A105 blind flange is precisely machined to ASME tolerances and finished with a raised face (RF) sealing surface for secure, leak-free connections in large-diameter pipelines. The flanges are fully compliant with NACE MR0175/ISO 15156, ensuring suitability for sour service and critical offshore applications.
Comprehensive Quality Documentation
Haihao Group provided a complete documentation package to guarantee full traceability and compliance for this order, including:
- 
EN 10204 3.1 DNV-approved Mill Test Certificates 
- 
Original raw material MTC 
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Hardness test report and heat treatment record, specifying heat treatment type and cooling medium 
- 
Ultrasonic Testing (UT) report confirming defect-free integrity 
All quality reports were issued according to international marine standards, confirming that each ASME B16.47 Series A blind flange meets the mechanical, chemical, and dimensional requirements of ASTM A105 and DNV certification.
Precision Engineering and Global Reliability
The 48-inch 150# blind flange represents Haihao Group’s expertise in large-diameter carbon steel flanges. Designed to close the ends of piping systems, these components are widely used in oil & gas, marine, and petrochemical projects where both safety and durability are critical.
Haihao Group’s advanced forging, heat treatment, and CNC machining capabilities ensure every flange achieves:
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Excellent pressure retention and fatigue resistance 
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Dimensional accuracy per ASME B16.47 requirements 
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Smooth raised-face sealing for long-term reliability 
Trusted Partner in Marine and Offshore Piping Solutions
As a DNV-approved flange manufacturer, Haihao Group has long been a trusted supplier of ASME and ASTM standard flanges to clients worldwide. From blind, weld neck, slip-on, and lap joint flanges to custom-engineered solutions, the company provides complete support for marine, offshore, and industrial piping systems.

 
		