Technical Information
Hydraulic Performance
The hydraulic performance of the pipe can be significantly improved as the PVC panels are placed close to the existing surface resulting in a minimum loss of diameter while providing a smoother surface to the flow. For example, a 1.4 metre RCP lined with Danby may result in a finished internal diameter of 1.3 metre and would have a theoretical flow capacity of 136% of the original RCP line. By comparison, HDPE slip liner of SDR 32.5 would have an outside diameter of 1.2 metre and a maximum inside diameter of 1.1 metre and would result in a relative flow capacity of only 92% of the original line (the roughness factor, n, is essentially the same for both HDPE and PVC).
Relative flow Capacity (Q1/Q2)
(% of Original Pipe Capacity)
| D1/D2 | Q1/Q2 |
| 1.00 | 150 |
| 0.95 | 131 |
| 0.90 | 113 |
| 0.85 | 97 |
Q1/Q2= (n2/n1) * (D1/D2)ˆ 8/3; assumes S1=S2
n1=0.01 (PVC Liner), n2= 0.015 (cement or brick)
D1 = diameter of liner, D2 = diameter of original pipe