b. Pump station operation in parallel.
Parallel operation is not
normally used on petroleum pipelines but can be found in terminal operations
due to the capability to move high volumes of fuel. Parallel installation
increases flow rate capability without increasing head capacity. The lower
the head capacity, the closer together pump stations must be located;
therefore, the more pump stations required for a given length of pipeline.
Only the 6-inch, two-stage pump can be placed in parallel operation.
Paralleling means that fuel flows through both stages at the same time.
This increases the volume and output of the pump.
The pump is put into
parallel by using Y flanges (Figure 4), which are attached the suction and
discharge side of the pump.
The 6-inch, two-stage pump with stages in parallel