Page 40 - +GF+ PPR Aquasystem Catalogue 2017_Neat

Position of the Flexible Arms

The low modules of elasticity of thermoplastics allows changes in length to be absorbed by special pipe
sections where pipe supports are positioned so that they can take advantage of the natural flexibility of
the material.

The length of such sections is determined by the diameter of the pipeline and the extent of the thermal
expansion to be compensated.

In order to simplify design and installation, the temperature of the pipe wall, a third factor, will not
be taken into account, especially since most pipes are installed in an environment with ambient
temperature in the range of 5 to 30°C.

Arrangement of fixed point support clamps (PF)
Fixed points direct thermal expansion of the pipe in
the desired direction. Fixed points should always be
installed at the fitting and should support it on both
sides or be installed in between two fittings.

Sliding support clamps (PS)
Sliding fasteners allow an axial movement of the
pipe. The clamp must be in line with the pipe.
Sliding clamps must be lined with rubber inserts
suitable for plastic pipe movement to avoid pipe
damage.
PS : sliding point PF: fixed point
PF : fixed point
LBF : flexible arm length

Example for the assessment of the flexible arm
Data: L = 10 m
d = 50 mm
T installation = 15 °C
T max operation = 80 °C
.
.
L = 0,15 10 65 = 97,5 mm

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