Page 37 - +GF+ PPR Aquasystem Catalogue 2017_Neat
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Regression Curve
The regression curves affect pipe life depending on the fluid pressure, temperature and outer stress (see chart).
Regression curves
The diagram shows the lowest
life features according to
DIN 8078 standards and life
test results concerning the
polymer used, in order
to confirm the high resistance
to pressure and temperature
of AQUASYSTEM ®
technical features
Hydrostatic stress:
Expressed in megapascals, induced in the wall of pipe when a pressure is applied using water as a medium.
Using Hydrostatic stress and dimensions, the maximum working pressure can be calculated with the following equation:
Example
The formula joining these parameters is :
T = 60°C Continuous operating life: 50 years
P = maximum inner pressure From the regression curve the result is: R = 4,9 Mpa
d = outer diameter
s = thickness Calculation (from the formula)
R = outer stress P= 19,7 bar
Or P = 13 bar
(using safety coefficient of 1.5)
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