CH 562 SURFACE SHIP STEERING SYSTEMS Flashcards
There are 3 types of surface steering control systems
hand (electric), hydraulic telemotor, and digital.
This is used to control systems that are designed to operate the linkage-controlled servo valve on the main pump or the direct link to the swashplate.
Hand (electric)
The helm wheel, sometimes called the steering wheel or trick wheel, is part of a
synchro transmitter assembly
The wheel is mechanically
connected to the Helm Order Indicator pointer so the
helmsman can see the position of the wheel and the command
angle.
These synchro transmitters send signals to
the synchro receivers in the steering gear room
this is used for voltage imbalance to control the component that turns the input shaft of the differential.
The servo amplifier
The helm order/rudder angle pointers are mounted with
concentric shafting
The nonfollow-up controller (NFC) is a small control panel
used to steer the ship from the
bridge
What kind of switch is the steering mode selector, that allows the helmsman to select the method of steering the ship.
rotary switch
The faults are identified on the steering alarm indicators panel near the
helm at the ship control console.
Electrical cables carry steering control signals between remote steering stations and
the steering gear room
Duplicate cables are provided and are separated between the port and starboard sides of the ship to increase
the survivability of the system.
The amplifiers convert the electrical signals from the helm synchro transmitter assembly into control signals that operate
the input shaft of the differentials
Steering control amplifiers develop the signal that is used for controlling the
Rotary Hydraulic Power Unit (RHPU)
The switchboard is used to transfer control between steering stations and to
secure remote control signals when operating with the
differential trick wheels
The switchboard also functions as a distribution point for transmitting signals from the
bridge to each of the RCSUs
The differential mechanism measures any difference between the helm angle and the rudder angle and strokes the pump swashplate to
eliminate the difference
What kind of valve valve is within the RHPU controls the direction of motor rotation
4-way directional
When the motor is positioned to obtain the correct rudder
angle, hydraulic fluid flow from the auxiliary pump is directed away from the directional valve through a
bypass valve
The bypass valve is
solenoid operated
What kind of motor does the Rotary Hydraulic Power Unit (RHPU) contain
low inertia fluid motor that rotates the input shaft of the differential
What kind of valve is within the RHPU that controls the directon of the motor rotation
4-way directional valve
What provides a stabilizing influence on the servo motor rotation
tachometer
The primary function of servo motor systems is to
translate the electrical
signals from the remote steering stations into a mechanical rotation so that the steering commands can be input into the differential
The helm wheels are manually operated and perform the function of the
RHPU or servo unit
What equipment provides the automatic test capability to detect, localize, and isolate faults within the steering system.
Built-In-Test (BIT)
The wheel is mechanically attached to potentiometers and a
synchro transmitter
Critical faults include
a. Low hydraulic fluid level in the head tank
b. High hydraulic fluid temperature in the main pump case drain piping
c. Electric motor overload
d. Loss of ac power
Major faults include:
a. Low hydraulic fluid level in the head tank
b. High fluid temperature in the supply tank
c. Low servo pressure
d. Servo control error
e. Low replenishment pressure
f. High motor temperature
