Hale 4DK Series - Manual (Page 7)

Manual p/n: 029-0020-79-0 7
4DK Series Pumps
SECTION 1 INTRODUCTION
Centrifugal Force
Hale 4DK series pumps are self-priming
centrifugal pumps that operate on the prin-
ciple of centrifugal force created by a rapidly
spinning disk. Figure 1 below shows that an
amount of fluid has been placed at the center
of a disk.
The disk is rotated at some speed, and the
fluid is thrown from the center toward the
outer circumference of the disk. The velocity
at which the fluid travels from the center
directly relates to the diameter of the disk and
the speed of rotation.
When a fluid is confined in a closed container
(such as the pump body), the velocity is
converted to pressure and pressure rises to a
level that depends on the speed of rotation.
There are three interrelated factors that
regulate the performance of a centrifugal
pump:
❑ SPEED (RPM) If the speed of rotation
increases with flow held constant, fluid
pressure increases.
❑ PRESSURE Pressure is usually
measured in Pounds Per Square Inch
(PSI or BAR).
OVERVIEW
Hale 4DK Series pumps are designed for han-
dling fuel or demineralized water in the aircraft
service industry. Hale 4DK series pumps are
self-priming and driven primarily by a split-shaft
4DK series gearbox.
Models of 4DK pumps are as follows:
4DK: The 4DK pump has a 4” (102 mm)
Victaulic suction connection and one or two 4”
(102 mm) Victaulic discharge connections, facing
either the front or rear. This pump is available
with a 1:2.96 or 1:3.40 gearbox ratio for capaci-
ties of 600 GPM (2,271 LPM).
The 4DK-30 model pump is built to strict military
standards, and is equipped with a pneumatic shift
indicator switch.
4D6K: The 4D6K model pump is built for high-
performance commercial applications. The
design of the 4D6K allows for quick field mainte-
nance and serviceability. The pump has a 6”
(152 mm) Victaulic suction connection and a
front-facing 4” (102 mm) Victaulic discharge
connection. This pump offers 1:2.96 and 1:3.40
gearbox ratios for peak performance in capacities
of approximately 750 to 800 GPM (2,839 to
3,028 LPM).
Both models are available with an optional
mechanical 10:1 tachometer drive mounted on
the pump shaft.
For an illustrated pump overview, see heading
4DK Series Overview, beginning on page 38.
PRINCIPLES OF OPERATION
This section reviews the principles of operation of
Hale 4DK series pumps and provides a descrip-
tion of the pump component parts.
Figure 1: Centrifugal Force