🔷 What is PN in piping systems?

PN (Pressure Nominal) is a nominal pressure rating system used under the European EN standard. It defines the pressure capacity of valves, flanges, and piping components at a reference temperature.

Common PN ratings include: PN6, PN10, PN16, PN25, PN40, PN64, PN100.

👉 Simply put:

• Higher PN = higher pressure capacity
• However, actual pressure depends on temperature and material

  

⚙️ What do PN16, PN40, PN100 mean?

Common PN ratings:

• PN16: approx. 16 bar (commonly used for water, HVAC systems)
• PN40: approx. 40 bar (steam, oil, light industrial systems)
• PN100: approx. 100 bar (high-pressure industrial systems)

⚠️ Note: These values are based on standard conditions. Pressure capacity decreases as temperature increases.

🔄 What is the difference between PN and ANSI Class?

Both PN and ANSI Class are pressure rating systems, but they differ in measurement systems and standards.

📊 PN vs ANSI Class comparison (approximate)

⚠️ This is only an approximate comparison, not an exact conversion.

📐 Why PN and Class cannot be directly converted?

The differences come from:

• 🔥 Operating temperature effects
• 🧱 Material grades (A105, F304, F316, etc.)
• 📏 Different design standards (EN vs ASME)
• ⚙️ Different safety calculation methods

👉 Therefore, PN and Class cannot be directly converted 1:1.

🏭 When to use PN or ANSI Class?

• PN (EN standard):
  • Water systems, HVAC, general industrial use
  • Projects in Vietnam and Europe
• ANSI Class (ASME standard):
  • Oil & gas, chemical, power plants
  • International high-pressure applications

❌ Common mistakes

• Assuming PN16 = exactly Class 150
• Directly converting PN to Class without considering temperature
• Mixing PN and Class in the same piping system

🏁 Conclusion

PN16, PN40, PN100 and ANSI Class ratings are important standards used to define pressure capacity in piping systems.

👉 Key takeaways:

• PN = European standard (bar-based)
• Class = ASME standard (temperature-dependent)
• No exact 1:1 conversion
• Selection must consider pressure + temperature + material

📞 Contact Information

PHUC MINH ENGINEERING – pm-e.vn provides industrial valves, flanges, gaskets, and piping accessories according to international standards.

• 🌐 Website: pm-e.vn
• 📧 Email: info@pm-e.vn
• 📱 Hotline: +84 907 450 506 – +84 902 720 814 – +84 902 800 728