Routing algorithm for pipelines

I have to create an algorithm for routing purposes in pipeline industry. Like we have 4 pipelines available and in between there can be either injection of oil or it can be taken out at any station. If we have the capacity of 30000 units of volume and we have to transport 35000(nominations from shippers) then we need to cut down the nominations. But how to cut it down and how to schedule so that we can accomodate maximum volume?

I have tried to solve it by using Travelling Sa开发者_如何转开发lesman Problem(TSP) and other NP-Hard problems but did not succeed.

This sounds along the lines of the maximum flow problem.

I think what would really help is to visualize the problem on a graph. It sounds like only you have 4 edges (pipelines), but you don't mention how many stations you have.