Aft Steering Flashcards
What is the max Rudder travel rate?
5.5 degrees per second
What is the normal Rudder travel?
35 degrees
At what Rudder angle is the Copper Stop used?
37 Degrees
At what Rudder Angle is the Steel Stop used?
38 Degrees
Where are the Copper and Steel Collars mounted?
At each end of the Tie Rod
What happens if the Ram over travels to 37 degrees Rudder Angle?
The Ram Stop Block will hit the Copper Stop
What happens when the Copper Stop is crushed?
The Steel Stop will engage the Ram Stop Block
What are the two subsystems of the Steering Gear Machinery?
The Steering Gear Hydraulic Oil System and the Fill and Drain Pump Unit
What does the Steering Gear Machinery System do?
Provides mechanical advantage through the use of hydraulics to position the rudder
How many Hydraulic Power Units(HPU) are there?
2 per Rudder
What do the Hydraulic Power Units (HPU) do?
They provide hydraulic pressure to move their associated Rudders
How are the Hydraulic Power Units(HPU) numbered?
1A, 1B for Starboard and 2A, 2B for Port
What does the Main Pump do?
Supplies the high pressure oil to move the Ram Assembly
What kind of pump is the Main Pump?
Variable displacement axial piston pump
What is the discharge pressure for the Main Pump?
250-300 psig at zero Main Pump stroke and 2000-2400 psig when on stroke
What does the Auxiliary Servo and Replenishment pump do?
Supplies control oil to the main pump Control Servo Assembly and the HPU Transfer Valve
What kind of pump is the Auxiliary Servo and Replenishment pump?
Sliding vane type positive displacement pump
The Auxiliary Servo Replenishment pump is driven by what shaft?
Same shaft as the Main Pump
What is the normal discharge pressure for the Auxiliary Servo Replenishment Pump?
650-700 psig
What does the Auxiliary Pump provide?
- Controls the stroke of the HP pump
- Controls the position of the HPU Transfer Valve.
- Provides make-up oil to the HP oil system.
- Cools the Main Pump Casing.
What is the purpose of the HPU supply tank?
Provides a continuous hydraulic fluid source to the auxiliary pump inlet
The HPU supply tank receives temperature regulated, filtered fluid from what?
The main pump housing
Oil temperature is monitored for the following conditions:
- Oil temp fails to reach 100°F after running for an hour
2. Oil temp rises above 140°F at any time.
If oil temperature fails to reach 100°F after running continuously for one hour what kind of fault is it?
Minor Fault
If oil temp rises above 140°F at any time what kind of fault is it?
Major Fault
How many Hydraulic Fluid Filters per HPU Filter oil entering the HPU?
2
Filter DP High is what psid?
35
Hydraulic Fluid Filters bypasses at what psid?
50
Hydraulic Fluid Filters high DP causes what kind of fault?
Minor Fault
What is the purpose of the Servo Pressure Switch?
Provides a HPU RUN signal when servo pressure exceeds 200 +/- 20 psig and a Servo oil low pressure at 200 +/- 20 psig
What kind of fault does the Servo Pressure switch give?
Major Fault
What is the Hydraulic Fluid Cooler?
A single-pass tube cooler which utilizes firemain as a cooling medium.
What does the Temperature Regulating Valve do?
Senses Cooler inlet temp and bypasses the hydraulic oil around the Cooler when temp is below 120°F
The Valve Block contains what?
- Servo Relief Valve
- Replenishment Relief Valve
- Two Replacement Check Valves
- Two Main System Relief Valves
The Servo Relief Valve is set at what psig?
700
The Replenishment Relief Valve is set at what psig?
200
The Two Main System Relief valves are set at what psig?
2640
What kind of Accumulator is used on the HPU?
A nitrogen-charged bladder-type Accumulator
What is the purpose of the Accumulator?
Provides replenishment fluid during transient conditions ( large rudder movements ).
What is the capacity of the Accumulator?
2.5 gallons
What is normal capacity for the Accumulator
1.25 gallons
What psig is the Accumulator charged to?
100
What kind of valve is the Servo Valve?
Electronically operated solenoid valve
Where is the Servo Valve located?
On top of the Valve Block
What does the Servo Valve do?
Receives an electrical signal from the LCU and sends servo oil to the Pump Control Servo Assembly
What does the Transfer Valve do?
Shifts control or the Rudder between the two HPU’s
What is the purpose of the Head Tank Assembly?
Provides a positive head pressure to the Auxiliary Pump
What is the FADPU?
Fill and Drain Pump Unit
What is the Fill and Drain Pump Unit?
It is the fill, flushing, and transfer station for the Steering Gear Machinery and the Emergency Manual Steering Operating Station
What are the major components of the FADPU?
- FADPU Electric Motor Driven Pump
- Suction Strainer (238 micron)
- Discharge Filter (6 micron)
- Discharge Selector Valve
- Port and STBD Steering Control Valves
What is the Discharge Selector Valve on the FADPU?
A manual, three position valve used to select one of the two Ram Units
How many Ram Units can the FADPU operate?
Only one Ram Unit and attached Rudder can be operated at one time
What kind of fault does the Servo Pressure switch give?
Major Fault
What is the Hydraulic Fluid Cooler?
A single-pass tube cooler which utilizes firemain as a cooling medium.
What does the Temperature Regulating Valve do?
Senses Cooler inlet temp and bypasses the hydraulic oil around the Cooler when temp is below 120°F
The Valve Block contains what?
- Servo Relief Valve
- Replenishment Relief Valve
- Two Replacement Check Valves
- Two Main System Relief Valves
The Servo Relief Valve is set at what psig?
700
The Replenishment Relief Valve is set at what psig?
200
The Two Main System Relief valves are set at what psig?
2640
What kind of Accumulator is used on the HPU?
A nitrogen-charged bladder-type Accumulator
What is the purpose of the Accumulator?
Provides replenishment fluid during transient conditions ( large rudder movements ).
What is the capacity of the Accumulator?
2.5 gallons
What is normal capacity for the Accumulator
1.25 gallons
What psig is the Accumulator charged to?
100
What are Port and STBD Steering Control Valves?
Manual, three position valves used to direct oil flow to either side of the selected Ram Unit
What is the only common connection point for the Steering Gear Machinery?
Storage Tank Assembly
What does the Storage Tank Assembly do?
Receives oil from the FADPU Steering Control, Fill Relief, or Emergency Steering Relief Valves
