HOPM COMPONENTS
CPP PUMP LOGICS
PURPOSE AND FUNCTIONS
COMPONENTS OF CPP SYSTEM
Miscellaneous
100
THIS IS SET AT 500 PSIG, PREVENTS OVER PRESSURIZATION OF THE OD BOX
WHAT IS THE AUXILIARY RELIEF VALVE
100
THE ELECTRIC CPP PUMP WILL AUTOMATICALLY STOP WHEN THE ATTACH CPP PUMP OIL DISCHARGE FLOW RATE EXCEEDS WHAT GPM?
WHAT IS 120 GPM
100
WHAT IS THE MAIN FUNCTION OF THE PROPELLER SYSTEM?
PROPEL THE SHIP THROUGH THE WATER
100
WHAT IS THE CAPACITY OF EACH SUMP IN THE MAIN SPACE?
MAIN ONE SUMP
Capacity: 1202 Gallons Normal Capacity: 961 Gallons High Alarm: 1142 Gallons Low Alarm: 721 Gallons
MAIN TWO SUMP
Capacity: 1283 Gallons Normal Capacity: 1026 High Alarm: 1219 Gallons Low Alarm: 770 Gallons
100
This maintains a static head pressure on the oil in the hub when the system is secured, preventing seawater from leaking past the blade seals into the system
What is Head Tank
200
WHAT FILTERS THE OIL DISCHARGED FROM THE TWO PUMPS?
WHAT IS 25 MICRON QUADRAPLEX FILTERS.
200
CPP pump logics are only available if the electric CPP pump is placed in _____ at the UCC.
AUTO
200
Hydraulic oil is used to vary the angle of attack of the propeller blades, otherwise known as ____?
PITCH
200
This component is capable of supplying sufficient oil pressure for normal CPP operation (approximately 88 SRPM and above), and is considered the primary pump.
What is the Attached Pump
200
The HOPM filters divide the oil into two types what are they called?
Control oil: Used to move the auxiliary servo piston located in the Oil Distribution (OD) box and is regulated to 400 PSIG.
Power Oil (high-pressure oil): Used to move the main or hub servo located in the propeller hub assembly. Normal pressure is 500-800 PSIG, but can get as high as 1000 PSIG
300
WHAT IS SET AT 1000 PSIG, WHICH PROTECTS THE SYSTEM FROM OVERPRESSURIZATION?
MAIN RELIEF VALVE
300
When the high-pressure oil flow to the OD box drops below 90 GPM, the electric CPP pump will automatically ____?
RESTART
300
How does the system provides ahead and astern propulsion thrust by changing what?
The pitch of the propeller blades without changing the direction of the propeller shaft rotation.
300
What component is considered the heart of the CPP system?
What is Hydraulic Oil Power Module (HOPM)
300
Who is authorized to set emergency ahead pitch?
CO
400
WHAT REMOVES PARTICULATE MATTER FROM THE CONTROL OIL GOING TO THE OD BOX?
DUPLEX CONTROL OIL FILTERS
400
HOW MANY SECOND TIME DELAY DOES PUMP LOGICS INCORPORATE?
3 SECONDS
400
How is pitch measured?
measured in Feet
400
This contains the aux servo piston, which positions the valve rod. Each shaft has an this mounted on the forward end of the gear casing. Its purpose is to control the position of the blades by positioning the valve rod, which in turn directs high-pressure hydraulic oil in the hub
What is Oil Distribution Box (OD)
400
Emergency ahead pitch can not be set if these two components are the cause of the casualty?
What is the OD box and the Hub
500
WHAT IS SET AT 400 PSIG, PROVIDES THE PROPER CONTROL OIL PRESSURE TO THE OD BOX
AUXILIARY REDUCING VALVE
500
WHERE ARE THE ELECTRIC AND ATTACH CPP PUMPS LOCATED IN MAIN ONE AND MAIN TWO?
ATTACH PUMP LOCATED INBOARD SIDE OF MRG CONNECTED TO LOWER SECOND REDUCTION PINIONS.
ELECTRIC PUMP LOWER LEVEL INBOARD OF REDUCTION GEAR
500
What is normal and maximum pitch range?
normal= -45 percent (full astern) to +100 percent (full ahead).
maximum= -61 percent astern to +120 percent ahead.
500
This is located near the OD box, it directs the flow of hydraulic control oil from the HOPM to the control oil section of the OD box, in response to an electrical or manual pitch change command. The assembly consists of a manifold block, two four way changeover valves, an electro-hydraulic servo control valve, and a manual four-way control valve
What is Valve Control Block
500
There are three modes of controlling pitch, they are selected using changeover valves located on the valve control block. What are the modes and describe each mode (location and how you operate each mode)
MANUAL: Moving the manual lever (joystick) on the manual servo valve to attain desired pitch. This controls pitch at the OD box using local scale.
AUTO: Pitch is controlled remotely from the UCC or the Bridge Control Unit (BCU). The remote control features are discussed later in this chapter.
OFF: Used when the hand-operated hydraulic pump is needed to set pitch and when conducting PMS. This control mode is commonly referred to as “EMERGENCY PITCH”.
