Most common rating: PN20
PPR-AL Stabi pipe is typically available with a PN20 rating. PN20 means 20 bar (290 psi) at 20°C. This is the standard for most applications. Example: residential and commercial hot water systems.
PN25 rating for higher pressures
Some manufacturers offer PN25 Stabi pipes. PN25 is 25 bar (362 psi) at 20°C. This is for more demanding industrial systems. PPR-AL Stabi pipe with PN25 handles higher pressures safely.
How PN ratings work
The PN number indicates the maximum working pressure. This pressure is expressed in bars (1 bar = 14.5 psi). The rating applies at a reference temperature of 20°C. PPR-AL Stabi pipe pressure capacity decreases at higher temperatures.
Temperature derating for pressure
At 20°C, PN20 pipe handles 20 bar. At 70°C, the same pipe handles 10 bar. At 95°C, the rating drops to 7 bar. PPR-AL Stabi pipe follows this standard derating curve.
Nominal diameter and pressure
Pressure ratings also vary with pipe diameter. Smaller diameters often handle higher pressures. Larger diameters may have slightly lower ratings. PPR-AL Stabi pipe ratings are validated for each size.
SDR (Standard Dimension Ratio)
Pressure rating relates to the SDR value. SDR is the ratio of diameter to wall thickness. A lower SDR means a thicker wall and higher pressure. PPR-AL Stabi pipe uses SDR 6 and SDR 7.4 for PN20.
Example: residential hot water system
A home hot water system runs at 4-6 bar typically. PN20 pipe provides a 3x safety margin. PPR-AL Stabi pipe is more than adequate. Example: a 5 bar system at 60°C is well within limits.
Example: high-rise building water supply
A 20-story building needs a booster pump. The pump delivers 12 bar pressure. PPR-AL Stabi pipe with PN25 is required. Example: safe for a tall building’s domestic water supply.
Example: industrial heating system
An industrial process needs 95°C water at 6 bar. The derated PN20 pipe handles 7 bar at 95°C. PPR-AL Stabi pipe is suitable for this application. Example: a manufacturing plant with high-temperature heating.
Pressure testing requirements
Stabi pipes must be pressure tested after installation. Typical test pressure is 1.5x the working pressure. For PN20, test at 30 bar (435 psi). PPR-AL Stabi pipe passes this test easily.
Max continuous vs peak pressure
PN rating is for continuous operating pressure. Short pressure spikes can exceed PN by 10-20%. The pipe can handle brief pressure surges. PPR-AL Stabi pipes accommodate typical system surges.
Final PN summary
PPR-AL Stabi pipe is available in PN20 and PN25 ratings. PN20 is standard for residential and commercial use. PN25 is available for industrial applications. Pressure ratings decrease at higher temperatures. Check the derating curve for your operating temperature. Match the PN rating to your system’s maximum pressure. Always consult manufacturer data for exact ratings. Example: choose PN20 for most systems; PN25 for high-rise or industrial use.
