The description you provided look like it would be covered by the ConveyorBelt block rather than the pipeline. The conveyor belt assumes that any bulk material (and fluids are bulk materials in AnyLogic) takes a specific amount of time to reach the other side, based on the speed and length of the belt. You can have it be fed for 1h, then idle for 15min, then fed again for 1h, and it will show off on the output end of the conveyor belt after a fixed delay (based on speed/length).