b. Line fill is shown on the left - hand vertical scale. The location of terminals (base, intermediate, head),
and pump stations are located by their line fill distance downstream from the base terminal.
c. The product batch identification within the line fill is marked on the graph indicating its beginning and
ending points.
d. Time is plotted on the horizontal axis. Each day begins at 0001 and ends at 2000. However, if the
demand for product is high, pumping could continue for 24 hours.
e. To determine product location in the pipeline, time distance is involved.
EXAMPLE 1: Batch 2-20-10 is batched at 0700. The pipeline fill (intermediate terminal) is 20 Mbbl and the
pumping rate is 2 Mbbl per hour. Take the line fill which is 20 Mbbl and divide it by 2 Mbbl. This lets you know
that the product started in the pipeline will take 10 hours to arrive at the head terminal. Take the 10 hours and add
it to your start time of 0700. This lets you know that at 1700 hours your fuel will have reached the terminal. To
find out how many hours it will take for your batch to pass, take the number of Mbbl of your batch and divide it
by the pump rate. Then add that number to the number of hours that it took to get to the head terminal. For our
example we found that it took 10 hours. So for our example, we will take our batch 2-20-10. Since we know that
we have 10 Mbbl (this comes from the underlined Mbbl) we then divide this number by the pumping rate of 2
Mbbls which gives us 5 hours. We then add that 5 hours to our 1700 which gives us the grand total of 2200 for
this batch to pass.
NOTE: You must always know the pumping rate.
EXAMPLE 2: By knowing when a product is started into the pipeline and knowing the quantity to be placed into
the pipeline, you can determine the time the total batch is placed into the pipeline. Start 16 Mbbl of jet fuel into a
pipeline at 0001 and pumping at 2 Mbbl the last of the batch is placed into the pipeline at 0800 (16 + 2 = 8).
f. Shutdown of the pipeline for scheduled maintenance, or due to unscheduled reasons such as sabotage or
pressure loss does not stop time from continuing to pass.
NOTE: A shutdown is indicated with a dotted line at the point of time shutdown takes place. If the shutdown
affects the complete pipeline, then the dotted line will extend from base to head terminal at the time shutdown
starts and a second dotted line at the point of time that pumping operations start up again. If the shutdown affects
only part of the pipeline, that part will be indicated by a dotted line indicating the part and time that shutdown
affects. If the pipeline is between the base and intermediate terminal, then only the product that is being pumped
out of the intermediate terminal to the head terminal is affected. The horizontal dotted line on the graph shows
the intermediate terminal between the shutdown start time and ending time where the start-up begins.
g. Stripping occurs when the flow is split between a terminal and the pipeline. A product is being pushed up
the pipeline and to a terminal along the pipeline. Product is received into the terminal while at the same time it
continues to flow up the pipeline.
NOTE: A stripping action is indicated with dotted lines showing the location and period of time that the stripping
action takes place. Where stripping takes, place the product flow changes. If the rate of flow prior to the point
that stripping starts is 2 Mbbl, the flow rate at the point of stripping and on past is reduced by half during the
period stripping occurs.
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QM5202
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