ISO 9967:1994

Thermoplastics pipes — Determination of creep ratio

The principle of the method specified is placing a cut length of pipe between two parallel flat horizontal plates, applying a constant compressive force for 1000 h (42 days), recording the deflection of the pipe at specified intervals so as to prepare a plot of pipe deflection against time, analysing the linearity of the data and calculating the creep ratio. Applies to pipes having a circular cross-section.