Roughness
| Pipe material |
|
Roughness |
| | |
[mm] |
| glass, lead, copper, brass drawn, plastic |
|
0 - 0.0015 |
| Welded steel |
new |
0.05 - 0.1 |
| evenly rusty |
<=0.4 |
| slight incrustation |
1 - 1.5 |
| severe incrustation |
2 - 4 |
| Steel electrogalvanised with zinc |
|
0.15 |
| Cast iron |
|
0.26 - 1 |
[VDI Wärmeatlas 4. Edition 1984, Chapter LB1 Page 2]
|