For indoor cold and hot water
supply installations, as follows:
– Class 1 (hot water 60°C) – design temperature related to service
life: 60°C/49 years + 80°C/1 year + 95°C/100 hours.
– Class 2 (hot water 70°C) – design temperature related to service
life: 70°C/49 years + 80°C/1 year + 95°C/100 hours.
INSTALLATION
For PP-R pipes that are not installed embedded in a protective sleeve
(where expansion takes place within the sleeve) and for large-diameter
pipes, measures to compensate for expansion must be taken already at the
design stage.
PP-R pipes have the expansion coefficient:
– PP-R (alpha) = 0.15 mm/m K,
– PP-R/FIBRa (alpha) = 0.088 mm/m K
– PP-R/Al (alpha) = 0.03 mm/m K.
For surface-mounted installation, the system must be secured
to prevent uncontrolled movement of the pipes.
Linear expansion is compensated between two fixed points. The system’s fixed points
are positioned near
branches, valves, or wall penetrations.
Fixed points are positioned so that the expansion forces
The variation in pipe length depending on pipe length and
temperature variation is calculated using the following formula:
(delta)L = (alpha) x (delta)T x L (delta)L = L-Lo
(delta)T = T – To
where:
(delta)L = total variation in pipe length [mm]
(delta)T = total temperature variation
(alpha) = linear expansion coefficient, [mm/m K]
T = operating temperature
To = installation temperature
L = pipe length at temperature T, [m]
Lo = pipe length at temperature To, [m]
Sliding points must be well secured to ensure
system alignment, support, and axial movement,
preventing vibrations and noise transmission. Calculation of the length
of the L-type expansion compensator
Where
Lb = length of the expansion arm, [mm]
d = pipe outside diameter, [mm]
(delta)L = total variation in pipe length [mm]
C = dimensionless material constant (C = 30 for PP-R)
PF: fixed point. PM: sliding point
Calculation of the U expansion compensator
The U compensator is an assembly of 2 L-type compensators, whose
length is calculated with the formula
above and the minimum width as follows:
Lc = 2 x (delta)L + ms,
Lc = minimum width of the compensator.
ms – safety width = 150 mm