PN20 rating is most common
PEX EVOH pipes typically have a PN20 pressure rating. PN20 means 20 bar (290 psi) at 20°C. This is suitable for most residential and commercial systems. Example: 20 bar is the standard rating.
PN16 and PN25 options
Some manufacturers offer PN16 (16 bar) pipes. PN25 (25 bar) is available for high-pressure systems. The exact rating depends on pipe construction and thickness. PEX EVOH pipes have various pressure ratings available.
SDR and pressure rating
Pressure rating is related to the SDR (Standard Dimension Ratio). SDR 6 has a higher rating than SDR 7.4. Thicker walls mean higher pressure capacity. PEX EVOH pipes follow the SDR rating system.
Temperature derating
Pressure ratings decrease at higher temperatures. At 20°C, PN20 handles 20 bar. At 70°C, the rating drops to 10 bar. At 95°C, it drops to 7 bar. PEX EVOH pipes require derating for hot water.
Cold water rating
At cold temperatures, pressure ratings are higher. The pipe can handle 25 bar at 10°C. This is due to the material's increased strength. PEX EVOH pipes have high cold water pressure capacity.
Example: residential hot water
A home has hot water at 60°C and 4 bar. PEX EVOH pipes easily handle these conditions. The pipe has a large safety margin. Example: a reliable, safe hot water system.
Example: high-pressure commercial system
A commercial system operates at 16 bar and 20°C. PEX EVOH pipes with PN20 are suitable. The pipe meets the system pressure requirements. Example: a safe, reliable commercial system.
Example: heating system at 80°C
A heating system operates at 80°C and 5 bar. PEX EVOH pipes have a derated pressure of 9 bar at 80°C. The pipe is well within its limit. Example: a safe heating system.
Pressure ratings by standard
ASTM and ISO standards specify pressure ratings for PEX. PEX EVOH meets these standards. The ratings are based on extensive testing. PEX EVOH pipes are certified to industry standards.
Pipe dimension marking
Sizes are marked as 20×3.4, 25×4.2, etc. The first number is the diameter (mm). The second number is the wall thickness (mm). PEX EVOH pipes have clear dimension markings.
Maximum operating pressure
The maximum continuous operating pressure is 20 bar. Short-term pressure spikes may be higher. The pipe can handle brief pressure surges. PEX EVOH pipes have a safety margin for surges.
Final pressure rating summary
PEX EVOH pipes typically have a PN20 rating (20 bar at 20°C). PN16 and PN25 are also available. Pressure ratings decrease at higher temperatures. At 70°C, the rating drops to 10 bar. At 95°C, it drops to 7 bar. Cold water ratings are higher. Always check the derating curve for your temperature. PEX EVOH pipes meet ASTM and ISO standards. Choose the correct rating for your system. Example: a reliable pressure-rated pipe.