API 605 Flanges Suppliers

API 605 flanges — now governed by ASME B16.47 Series A — are specifically designed to handle the mechanical and sealing challenges of large-diameter piping (from 26″ to 60″ NB), commonly found in high-capacity, high-pressure pipeline networks.

Key reasons for their preference:

1. Structural Integrity: The large weld neck hub ensures smooth stress distribution, reducing the risk of fatigue or failure in high-pressure lines.
2. Leak Prevention: Available in RF and RTJ face types, these flanges support strong sealing with spiral wound or metal ring gaskets.
3. Custom Bolt Patterns: Precision-drilled holes provide reliable alignment and gasket compression in large flange diameters.
4. International Compatibility: Dimensions conform to ASME standards, enabling global use without customization.
5. Ease of Maintenance: Ideal for process pipelines where large flanges must be disassembled during inspections or repairs.

This makes them a top choice in oil & gas terminals, refinery header lines, seawater intake pipelines, and offshore riser systems.

Installing large-diameter flanges like API 605 / ASME B16.47 Series A requires proper planning, equipment, and technical oversight due to their heavy weight and critical sealing role in high-pressure systems.

Important installation considerations include:

• Proper Alignment: Ensure precise bolt hole and gasket face alignment to avoid leaks and mechanical stress during tightening.
• Gasket Compatibility: Use spiral wound, metal jacketed, or RTJ ring gaskets suited to the selected flange face (RF or RTJ).
• Torque Sequencing: Apply torque in a crisscross pattern using calibrated torque wrenches to ensure uniform gasket compression.
• Face Surface Check: Inspect flange surface finish (typically 125–250 AARH) and flatness for sealing efficiency.
• Lifting Equipment: Use appropriate rigging or cranes, as sizes up to 60″ may weigh several hundred kilograms per piece.
• Fastener Grade: Use ASTM A193 / A194 bolts and nuts, compatible with the flange pressure class and temperature rating.

Correct installation ensures leak-proof operation, joint longevity, and safety compliance in critical service environments.

API 605 flanges (now ASME B16.47 Series A) are available in a wide range of materials and surface protection options to match the demanding requirements of various industries such as oil & gas, offshore, and chemical processing.

Common Materials Used:

1. Carbon Steel: ASTM A105, A350 LF2 (for low temperature), A694 F52/F60/F65 (for high pressure pipeline service)
2. Stainless Steel: ASTM A182 F304, F316, F321 – used in corrosive or high-temperature environments
3. Duplex & Super Duplex: ASTM A182 F51, F53, F55 – ideal for offshore and seawater service
4. Alloy Steel: ASTM A182 F11, F22 – suitable for high-temperature and pressure environments
5. Nickel Alloys & Inconel: For highly corrosive or special applications (available on request)

Typical Surface Coatings:

• Black Paint – for general rust prevention during shipping/storage
• Yellow Transparent Varnish – offers short-term protection in controlled environments
• Hot Dip Galvanizing – zinc coating for long-term corrosion resistance (especially for CS flanges)
• Anti-Rust Oil Coating – applied internally and externally on carbon steel flanges
• Customized Coatings – epoxy, PTFE, or ceramic as per client request or project requirement

Selecting the right material and protective finish depends on pressure rating, fluid media, operating temperature, and project location.

At Nutech Overseas, we are a trusted global supplier of API 605 (ASME B16.47 Series A) large-diameter flanges, catering to a wide range of industries and EPC contractors around the world.

Our export network spans across:

1. United States (USA)
2. Germany, Spain, Italy, France (Europe)
3. United Arab Emirates (UAE), Saudi Arabia, Oman, Qatar, Kuwait (Middle East)
4. South Africa, Egypt, Nigeria (Africa)
5. Indonesia, Malaysia, Philippines, Vietnam (Southeast Asia)
6. Australia, New Zealand
7. Brazil, Mexico, Chile (South America)

With a reputation for on-time delivery, strict quality control, and technical compliance, we ensure our flanges meet international codes and client-specific requirements. All export consignments are supported by full inspection documents, MTCs, test reports, and global shipping support.

Whether for offshore, refinery, petrochemical, or pipeline projects — We delivers reliable flange solutions across the globe.