Technical data

15
Determination of pipe wall thickness and pressure class Endurance diagram of PB 4137 (see also DIN 16968/16969)
Compressed Air Applications Manual | Selection of material and pipe system
2
0
°C
60°C
70°C
95°C
1
1
0
°C
50
40
30
20
10
9
8
7,5
7
6
5
4
3
2,5
2
1
0,9
0,8
0,7
0,6
0,5
0,1
1 10 10
2
Durability in h
Comparative stress in N/mm²
10
3
10
4
10
5
10
6
Durability in years
1 5 10 25 50
The comparative stress
indicates fracture
stress δB.
In other words, it shows
the maximum load for
the material in depend-
ence on the tempera-
ture and service life.
Curves without safety
factor.
The endurance diagram shows the interaction of
• temperature t =
0
C
• service life (durability)
• comparative stress δ = N/mm
2
or
MPa (megapascal)
Example:
Temperature = 70
0
C
Service life (durability) = 50 years
Comparative stress δB = 7.5 N/mm
2