pumped into an operating tank must pass through a
filter/separator. Provide a horizontal filter/separator on
the discharge line from the operating storage tank.
Filter/separators are required for all aviation turbine fuel
systems in facilities where the fuel is dispensed directly to
aircraft or is loaded on refuelers that eventually dispense
the fuel to aircraft. As a minimum for such facilities,
provide horizontal filter/separators as follows:
a) Design and construct horizontal filter/separators
in accordance with API Pub 1581.
(1) Class A - Use at points where fuel is
received from barges, tankers, pipeline, rails, and trucks.
At these points, the fuel will be expected to have higher
levels of dirt and water. Consider the use of cyclonic
separators or pre-filters (micronic filters) upstream of the
filter/separator. (Note: API 1581, Filter/Separators in the
1,200 gpm range may only be available in the vertical
(2) Class B - Use in the refueler supply piping,
truck receipt piping, supply piping to fuel hydrant systems,
and in operating tanks.
b) Design and construct horizontal filter/separators
in accordance with the American Society of Mechanical
Engineers (ASME) Code for Unfired Pressure Vessels. Construct
metal parts which will be in contact with the fuel, including
the shell, head, and internal attachments of 3003 or 5083
aluminum alloy. (The Air Force also allows interior epoxy-
coated carbon steel.) Include the following accessories:
(1) Piston-type differential pressure gauge with
1 psi (5 kPa) graduations across the elements.
Sight glass on the water sump.
(3) Hydraulically operated diaphragm control
valve in the main discharge piping with rate of flow and water
slug features. Include a manual check mechanism external to
the filter/separator to check the float. (The water slug