Pipelines expand with heat. Heat expansion is dependent on the mate‐
rial. Changes in length lead to tension within the installation. These ten‐
sions must be equalised with suitable measures.
The following are effective:
n
Fixed and gliding points
n
Expansion equalisation joints (expansion bends)
Heat expansion co-efficients of various pipe materials
Material
Heat expansion co-effi‐
cient
⍺
[
mm
/
mK
]
Example:
Length expansion with
pipe lengths L = 20 m
and
Δ
T = 50 K
[mm]
Viega Smart‐
press multilayer
pipe
0.03
30
Calculation example multilayer pipe:
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Given: Temperature difference
Δϑ
= 50 K; Pipe length L = 8 m; Pipe
⌀
= 20 mm
n
Required: Expansion bend length L
BS
n
Calculation:
– Beginning in the left-hand diagram: From 50 K temperature dif‐
ference on the x-axis up to the characteristic line for the 8 m
pipe length.
– Connect the intersection horizontally with the right-hand dia‐
gram up to the intersection of the characteristic line for pipe
diameter 20 mm.
n
Result: Read the value from the x-axis: L
BS
= 480 mm.
Length expansion
Length expansion and expansion bend length
Product information
Viega Smartpress
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