Technical Reference

NAB Valve Standards & Specifications: Complete Technical Reference

Published on March 13, 2026 | By Supreme Valves India

Understanding the applicable standards and specifications for Nickel Aluminum Bronze (NAB/NiAlBr) valves is essential for proper material selection, manufacturing, and quality assurance. This guide covers the key standards governing NAB valves.

Material Standards

ASTM B148 - Castings, Bronze and Bronze-Alloy

The primary material specification for NAB valve castings:

• Grade C95800: Primary grade for seawater service
• Composition: Cu 81%, Al 9%, Ni 4%, Fe 4%
• Product Form: Sand castings, centrifugal castings
• Heat Treatment: Not required; can be heat treated for improved properties

Other Relevant ASTM Standards

• ASTM B61: Steam or Steam-Joint Bronze Castings
• ASTM B62: Composition Bronze or Ounce Metal Castings
• ASTM B271: Copper-Base Alloy Castings
• ASTM B584: Copper Alloy Sand Castings

Valve Design & Manufacturing Standards

API Standards

ASME Standards

• ASME B16.34: Steel Valves - Flanged and Butt-Weld Ends
• ASME B16.5: Pipe Flanges and Flanged Fittings (up to NPS 24)
• ASME B16.10: Face-to-Face and End-to-End Dimensions of Valves
• ASME B16.47: Large Diameter Steel Flanges (NPS 26 to NPS 60)
• ASME B1.20.1: Pipe Threads, General Purpose

Testing & Inspection Standards

API 598 - Valve Inspection and Testing

• Shell test (1.5x rated pressure)
• Seat test (1.1x rated pressure)
• Backseat test
• Stem packing test
• Operation test (minimum 5 cycles)

API 607 - Fire Safe Testing

• 30-minute fire test at 1000°F (538°C)
• Post-fire seat leakage test
• Post-fire operating test
• Graphite or metal seats required

Pressure-Temperature Ratings

Quality Certifications

• ISO 9001: Quality Management System
• API 6D: Monogram Licensing (for applicable products)
• CE/PED: Pressure Equipment Directive (for Europe)
• Lloyd's Register: Type Approval
• DNV-GL: Type Approval

Key Design Considerations

• End Connections: Flanged (RF/RTJ), Threaded (NPT/BSP), Butt Weld, Hub End
• Face-to-Face: ASME B16.10 for flanged; API 608 for threaded
• Pressure Testing: API 598 or as specified by customer
• Marking: Per API 20E/20L or customer specification

Conclusion

Understanding and complying with applicable standards ensures NAB valves meet the required quality, safety, and performance criteria for marine and seawater applications. Always verify specific project requirements when selecting valves.