ANSI B16.5 Flange Standard Chart for Industrial Piping Systems

In industrial piping design and installation, flanges play a critical role in connecting valves, pipes, and equipment. One of the most widely used international standards is ANSI B16.5.

This standard defines the dimensions, pressure ratings, materials, and structural requirements for flanges used in high-pressure industrial systems.

1. What is ANSI B16.5?

ANSI B16.5 (also known as ASME B16.5) is an American standard that specifies requirements for:

• Pipe flanges
• Gaskets
• Bolting
• Pressure ratings and nominal sizes

This standard is widely used in:

• Oil & gas
• Chemical industry
• Power plants
• Heavy industrial systems

2. ANSI Flange Pressure Classes

ANSI flanges are categorized by pressure ratings (Class):

• Class 150
• Class 300
• Class 600
• Class 900
• Class 1500
• Class 2500

👉 Higher class means higher pressure resistance.

3. ANSI B16.5 Flange Standard Overview Table

Based on Nominal Pipe Size (NPS)

👉 Note: Exact dimensions (OD, bolt circle, bolt holes) vary by pressure class.

4. ANSI Flange Structure

A standard ANSI flange includes:

• Outside Diameter (OD)
• Bolt Hole Circle
• Number of bolt holes
• Bore size
• Flange thickness

5. Types of ANSI B16.5 Flanges

• Weld Neck Flange (WN)
• Slip On Flange (SO)
• Socket Weld Flange (SW)
• Threaded Flange (TH)
• Blind Flange (BL)
• Lap Joint Flange

6. Applications of ANSI B16.5 Flanges

ANSI standard flanges are widely used in:

• Offshore oil & gas systems
• Petrochemical plants
• Power generation plants
• Chemical pipelines
• High-pressure steam systems

7. Advantages of ANSI B16.5 Standard

• High design accuracy
• Excellent pressure resistance
• International compatibility and interchangeability
• Suitable for heavy industrial systems
• Globally recognized standard

8. Important Notes When Selecting ANSI Flanges

• Always select correct pressure class according to system requirements
• Check material specifications (carbon steel, stainless steel, etc.)
• Ensure compatibility with pipes and valves
• Consider operating temperature conditions

9. Reliable Supplier of Industrial Flanges & Valves

If you need technical consultation or pricing for ANSI B16.5 flanges, please contact:

Phuc Minh Engineering Co., Ltd
🌐 Website: pm-e.vn
📧 Email: info@pm-e.vn
📱 Hotline: +84 907 450 506 – +84 902 720 814 – +84 979 737 351

👉 We provide:

• ANSI, DIN, and JIS flanges
• Industrial valves and piping components
• Full CO-CQ documentation
• Technical support for projects

Conclusion

The ANSI B16.5 standard is one of the most important flange standards in industrial piping systems. Understanding its specifications helps ensure correct equipment selection, system safety, and long-term operational efficiency.