PART C - ANALYZE A MONTHLY PIPELINE SCHEDULE
The monthly pipeline schedule shows programmed movements through the pipeline. While it is known what
products are required for a 30 day period, a schedule can be prepared to determine how long it will take for
the product to reach its destination. After the product has started into the pipeline, the schedule is merely a
graph which shows line capacity in barrels (distance) plotted against time (hours). Preparation includes:
Before the graph is made, the number of hours a line is to be pumped each day must be determined.
Time is show from the beginning to the end of a given working day. The chart is drawn with the vertical
axis showing line fill.
The horizontal axis is drawn to show the time period.
Terminals are located on the chart by their respective line fill distance downstream from the base
terminal. The terminals are plotted vertically.
Each batch is labeled by product and batch number. Each type of product is marked on the graph with a
different color.
The distance in barrels divided by the pumping rate equals the number of hours it will take for a given
batch to reach a designated place.
The slope of the throughput lines stays constant when there is no intermediate stripping and when the
pumping rate stays the same. Stripping is when all or part of one or more batches is taken off the
pipeline at an intermediate terminal.
When products are taken into a terminal and half of the pipeline is shut down, this is plotted on the
monthly pipeline schedule. A dotted line on the horizontal time axis shows time the pipeline is shut
down. A second vertical dotted line shows when the pipeline goes back on stream. It should be noted on
the schedule that this is a static condition.
Stripping of product at a terminal is shown in the same manner as a static condition with horizontal and
vertical dotted lines. It is noted in the block formed by the dotted lines that a stripping action is taking
place.
The vertical line represents terminal and stations. The points at which the sloping lines intersect the
vertical lines show scheduled arrival times.
When all of the throughput lines have been drawn, the graph represents all scheduled pumping and
delivery operations for the month.
PART D - ANALYZE A DAILY PUMPING SCHEDULE
This schedule is used as a basis for preparing pumping orders. It is an abbreviated tabular form of the
monthly schedule for each day concerned. This schedule shows change and emergency needs. It is usually
prepared a week in advance so that the dispatching section can have a week's supply. The dispatching
section uses the daily pumping schedule to prepare the graphic progress chart and the daily pumping order.
PART E - ANALYZE A GRAPHIC PROGRESS CHART
The graphic progress chart provides a means of visualizing the positions of batches and their progress
through the pipeline. It is prepared one day in advance to indicate what is expected to take place. Its
construction is primarily the same as the monthly schedule except that it is for a 24-hour period. Preparation
includes:
Hours are shown on the vertical axis starting at midpoint on the graph, counting down the numbers of
hours in the pumping day.
Line fill, terminals, and pump stations are shown on the horizontal axis. Line fill is shown from the
midpoint at zero barrels (base terminal) moving to the right to intermediate terminal. Batches scheduled
to enter the pipeline are plotted on the left of the base terminal (the zero barrel line).
To plot the number of barrels scheduled to enter the pipeline at the base terminal, draw a horizontal line
to the left equal to the number of barrels scheduled to enter the line. Draw a broken sloping line back to
the base terminal time line. For example, the point where the broken line crosses the base terminal time
line shows the time that the new product must be started.
A solid sloping line is extended to the right from the base terminal time line at the same rate of flow. The
degree of slope of this line shows the pumping rate of the throughput line. If a terminal is told to strip
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QM 5096
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