The total length of the pipeline has little to do with the length that oil can be pumped in a pipe. This is because a pipeline is broken into many smaller segments between pumping stations. Stations are conveniently located either where required (see discussion below) or where another pipeline joins in.
Pipelines are rarely one single pipe between point A and point B. They have lots of smaller pipelines connecting into them. Each of these pipeline will have their own pump stations. These stations also help to divide the pipeline into segments. With segments, you can ensure that different oil is sent to specific locations.
You can think about the system from a logistics point of view. Any long pipeline is almost guaranteed to pass close to another location that either produces or consumes oil. It only makes sense to connect to these locations as the pipeline goes past.
Factors that affect the length that oil can be pumped in a single pipe
This is a large topic. Everything that affects regular pipe design also effects pipelines.
- Length of pipe
- Smoothness of pipe
- Temperature of the oil - Oil in pipeline is usually heated because warmer oil has a lower viscosity and is easier to pump
- Elevation changes
- Number and degree of turns
- Pressure capacity of pipe
- Diameter of pipe
- Allowable pressure drop between ends
- A lot more...
Structural Integrity of Pipe
The length of the pipe does not influence the strength of the pipe. All pipe lengths in a pipeline will be welded and tested to the same requirements.
