TM 10-3835-223-13&P
Section III. TECHNICAL PRINCIPLES OF OPERATION
Page
General
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Hose Reel System Principles of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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1-8. GENERAL
a. The hose reel system consists of two functional assemblies: a frame unit and power pack. The frame
unit contains the hose reels, hose, hydraulic cylinder, and hydraulic drive motor. The power pack contains an
electrically driven hydraulic pump, reservoir, and the necessary sequencing and regulating valves needed to
control the frame unit drive components.
b. The hose reel requires an external power source. The hose reel power cord must be connected to a
rough terrain forklift, 6X6 truck, or similar type vehicle having a 24 Vdc slave receptacle.
c. Operation of the hose reel system is conducted in two modes:
(1) Deployment. Unreeling of fuel hose during installation of the fuel hose.
(2) Retrieval. Reeling the fuel hose back onto the hose reel system following fuel facility
disassembly or preparation for movement.
1-9. HOSE REEL SYSTEM PRINCIPLES OF OPERATION
a. Power Pack. The power pack contains the control cable , sequence valve , valve station and power
unit required to operate the hose reel system and is connected to the frame unit by quick disconnect couplings.
No electrical connections between the power pack and the frame unit are required. The power pack can be
moved from one frame unit to another by disconnecting the hydraulic couplings and sliding the power pack
from the frame. One power pack is supplied for every six frame units.
(1)
Control Cable. Electrical power from the slave vehicle is received at the main enclosure
assembly (junction box) and distributed to the control cable. The control cable activates the hydraulic power
unit and controls operation of the frame hydraulic motor and cylinder by activating the valve station control
valves.
(2)
Sequence Valve. An internal spring loaded spool unseats when hydraulic pressure from
the pump reaches 1500 psi, allowing fluid to flow to the valve station. When system pressure is less than 1500
psi, the spool reseats and diverts fluid back to the reservoir. This valve ensures sufficient pressure is available
to operate the system..
(3)
Valve Station. The valve station controls the flow of fluid in the hydraulic system. By
reversing the fluid path to the hydraulic cylinder, the drive wheel and motor are repositioned to the opposite
hose reel. By reversing the fluid path to the hydraulic motor, the rotation of the hose reel is reversed.
Pressure relief, pressure regulating, and pressure reducing valves built into the valve station maintain
system pressure within safe operating limits.
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