product from the pipeline, the slope of the throughput line must be changed. The stripping action is
shown by a broken vertical line.
Any shutdown of the line is shown by a broken horizontal line. The solid sloping line will then be plotted
vertically for the duration of the shutdown.
When batches are moving ahead of or behind schedule, the dispatcher can either adjust the chart or
adjust the flow rate.
The points at which the sloping lines intersect the vertical line (terminal and stations) show scheduled
arrival times.
PART F - BATCHING PROCEDURES
Batching is the sequence in which two or more products are to be pumped and is the introduction of those
products into the pipeline in a sequence that results in the least formation of Interfacial material. In addition
to creating usable interfaces, the batching sequence also aids in quality and quantity control. Products likely
to be batched in the military multiproduct pipeline include MOGAS, diesel, kerosene, and jet fuel. Exact
batching procedures are not fixed. However, batches should be arranged to protect critical products and to
produce interface that can be used.
Batch Designation (Batch Number). This batch designation (number) has three parts. The first
part consists of the product code numbers. These code numbers are the sequence that the fuel is going into
the pipeline. The second part is the batch number. This number tells you how many batches of each
product have been pumped since the first of the fiscal year. The third part is the amount of mike of barrels
per batch.
Example: 2-15-20, JP-4, 15 batch fiscal year, and the amount of the batch is 20,000 barrels. (20M)
Detection of Batch Change. In control of product flow through the pipeline, it must be determined
where one batch ends and another batch begins. The following methods are used to detect batch changes in
the pipeline:
Gravity difference.
Color change.
Liquid buffers - MOGAS, neutral product.
Physical buffers - scraper, rubber ball.
Dye plug - colors.
Direct Personnel to Verify Arrival Time by Sampling. The terminal operations officer or the
dispatcher sets the time and frequency of observation before and during the batch change. The suggested
procedure is to begin taking readings 20 minutes before the expected arrival time of the interface at 5 minute
intervals. Five minutes prior to the arrival, take readings at 1 minute intervals when the interface arrives.
Samples are taken at intervals of one minute or less, and the sample line may be left open and flowing. This
ensures representative samples during the actual change.
Interface Control. Pipelines between bulk terminals are multiproduct lines. Interface is a mixing, or
commingling, between adjacent products in a multiproduct pipeline, an interfacial mixture. Problems caused
by pumping more than one product through a pipeline involves mixing of the products and disposing of the
mixed portions. The progress of the different products and the interfaces must be followed so that the
products can be taken off the line at the right place. The volume of interfaces depends on differences in
gravity and viscosity of adjacent products and on the pressure and velocity of the stream. It also depends on
the interior condition of the pipe, the number of pump stations, and the distance traveled by the interface.
The differences in gravity and viscosity will also effect interface disposal. Interface size can be reduced by
maintaining a pumping rate needed to keep the heaviest product in the line in turbulent flow. The size also
can be reduced by putting products in the line in proper batching sequence and by keeping the line
pressurized during a shutdown. Positive pressure will limit the speed of the interface and the interface
volume will be cut down whether the interface stops on level ground or on a slope.
Determine Interface Cut Points.. Cut points make up the interface between two products in the
pipeline and are controlled as follows: a head cut, midpoint gravity, tail, and heart cut.
8-4
QM 5096
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