Figure 60  General Gas 06 – Pipeline with Multiple Take-offs

The maximum operating pressure for this pipeline is 1000 psi.g. The delivery pressure required at point E is 400 psi.g. The pipeline has two take-off points (B & C) where gas is taken from the pipeline and one intermediate input point (D) where a further gas source supplies flow into the pipe line.


Since the flowrate between C & D is lower than in the other sections, pipe P3 has been sized with a smaller diameter (to save installation cost). The reduction in pipe diameter has resulted in the need for a gradual contraction fitting at the end of pipe P2 and a gradual enlargement fitting at the end of pipe P3. With this design the pressure at the main inlet point A is below the required maximum operating pressure of 1000 psi.g.


Note: Where the entry velocity in a particular pipe does not match the exit velocity from the previous pipe, this is because some flow has been extracted from the system or additional flow has been added in to the system, at the joining node.