Absolute Pipe Roughness
Absolute Pipe Roughness is usually defined for a material and can be measured
experimentally.
Following table gives typical roughness values in millimeters for commonly used
piping materials.
Surface Material
Absolute Roughness Coefficient - ε in mm
Aluminum, Lead
0.001 - 0.002
Drawn Brass, Drawn Copper
0.0015
Aluminum, Lead
0.001 - 0.002
PVC, Plastic Pipes
0.0015
Fiberglass
0.005
Stainless steel
0.015
Steel commercial pipe
0.045 - 0.09
Stretched steel
0.015
Weld steel
0.045
Galvanized steel
0.15
Rusted steel
0.15 - 4
Riveted steel
0.9 - 9
New cast iron
0.25 - 0.8
Worn cast iron
0.8 - 1.5
Corroding cast iron
1.5 - 2.5
Asphalted cast iron
0.012
Galvanized iron
0.015
Smoothed cement
0.3
Ordinary concrete
0.3 - 3
Well planed wood
0.18 - 0.9
Ordinary wood
5