Weights of CRA Clad or Lined Steel Pipes
The weight of a CRA clad or lined steel pipe shall be calculated as the sum of the backing steel (usually the carbon steel or alloy steel pipe, base metal) weight and the CRA layer weight. No matter how the CRA layer is bonded to the backing steel, it can also be regarded as a thin pipe mathematically. Thus, on the assumption that the pipe is plain-end, the weight shall be calculated using the equation below:
- W = [ 10.68 * ( D – T) * T ] + [ 10.68 * ( D – 2T – t ) * t * F ]
- W = [ 0.0246615 * ( D – T) * T ] + [ 0.0246615 * ( D – 2T – t ) * t * F ]
The former is in U.S. customary units while the later is in SI units:
- W: the weight of the clad or lined pipe, unit: lb/ft or kg/m.
- D: outside diameter of the backing steel pipe, unit: inch or mm.
- T: the specified wall thickness of base material, unit: inch or mm.
- t: the specified wall thickness of CRA layer, unit: inch or mm.
- F: is the correction factor for CRA materials due to different density.
The F values for some typical CRA materials are listed in below table:
CRA Material | Correction Factor, F |
---|---|
SS 304/304L | 1.019 |
SS 316/316L | 1.019 |
904L | 1.019 |
SS 317/317L | 1.019 |
Duplex 2205 | 0.995 |
Duplex 2507 | 0.995 |
Alloy 625 | 1.075 |
Alloy 825 | 1.038 |
Alloy C-276 | 1.132 |
Monel 400 | 1.121 |
Alloy 31 | 1.025 |
Titanium | 0.575 |
Zirconium | 0.829 |