Автоматизация на судне Automation. Bridge control.

Introduction

Automation is a subject which receives considerable attention in marine spheres; indeed it is becoming rare to find a ship that does not have some form of automatic means remote control for engines, power plants navigation and other equipment. Automatic control is more accurate and continuously watchful than manual control can ever be. Its installation, besides giving engine-room personnel more time to deal with maintenance problems, results in saving of fuel, maintenance costs, and out-of-service time due to failure. The major benefit of shipboard automation is the saving in operating cost resulting from a reduction of crew. This can readily be achieved through the installation of remotely operated valves in the ship's flow systems, the installation of sensors and the grouping of control and monitoring devices for convenient operation in the central control station.

The remote control room is air-conditioned and insulated. The main items which can be controlled from the room are: main engine, steam plants generators, auxiliary machinery, pressures, levels, temperature regulation and readings, alarms, communications, boiler service.

The latter includes visual instruments, status signal lights, alarms, graphic displays, and automatic data-logging equipment. Data logging improves supervision efficiency and often spots incipient faults before the human eye.

Automated systems developed and fitted to-date are, in the main, to control temperatures and pressures, to control combustion, steam pressures, etc. in steam plant and to control fuel systems, cooling and lubrication systems in Diesel plant. As more efficiency is called for, and pressures rise in Diesel machinery as do steam conditions for turbines, automatic supervision becomes increasingly necessary. A monitoring network increases the reliability in the operation of the ship, economizes overhaul and contributes to the ship's classification for unmanned engine room.

WORDS AND EXPRESSIONS:

to deal with maintenance problems — заниматься обслуживанием

to result in savings of fuel — в результате приводить к экономии топлива

due to failure— из-за поломки

remotely operated valves — клапаны дистанционного управления

sensors and monitoring devices — чувствительные элементы и контрольные приборы

status signal lights — сигнальные лампы

data-logging equipment — автоматические записывающие приборы (самописцы)

to improve supervision efficiency — улучшать эффективность контроля

to spot the faults— распознавать неисправности, ошибки

steam conditions — параметры пара

monitoring network — цепи контроля

unmanned engine room or unattended machinery space (UMS) — машинное отделение с безвахтенным обслуживанием

Exercise 1. Answer the following questions:

1. For what equipment can the remote control be used? 2. What does the automatic control result in? 3. Name the major benefit of shipboard automation, will you? 4. Where are the remotedly operated valve installed? 5. Enumerate the main items which can be controlled from central control room, can you? 6. What equipment does the control station include? 7. Say what parameters are automatically controlled in steam plants. 8. Say the same about Diesel plant. 9. What does a monitoring network increase? 10. Does the automatic control economize overhaul? If so_, prove your opinion.

Exercise 2. Write an annotation to the text.

BRIDGE CONTROL SYSTEM FOR MAIN DIESEL ENGINE

The Bridge Control System is a complete control system for main Diesel engines. Direct control from the bridge telegraph without manual intervention from the control room or engine room is possible.

On ships with periodically unmanned engine rooms the bridge control of the main engine is one of the most important functions. Standardized units, operational reliability, easy installation and a small number of spare parts are characteristic of this system.

Principles of operation. The bridge telegraph acts as a reference transmitter for the propeller speed and is continuously graduated in r.p.m. Alterations of the speed of the main engines are carried out according to fixed programs. They are set up to meet the requirements of each engine and of the ship with respect to overloading and manoeuvrability.

In some cases it is desirable to include safety functions, e.g low lubricating pressure, to obtain automatic speed reduction or to stop machinery. Such functions may be obtained by connecting the necessary number of pressure or thermo-switches. The functions which are required for starting and reversing the main engine are provided by logic circuits in the group unit. Such functions are: e.g. injection of toe starting air, positioning of the camshaft and fuel injection during starting. The output from the logic circuits is converted to a suitable power level for control of mechanical actuators on the main engine.

The Bridge Control System has the following basic equipment:

On the bridge - bridge telegraph, control panel, alarm buzzer. On the control desk — order repeater, control panel, alarm bell.

In the engine room — group unit with power supply and circuits for control and indication.

On the main engine - servomechanism, position switches, tachogenerator, electric, pneumatic or hydraulic actuators. The bridge telegraph is used for manual and automatic control. Two synchros are connected to the scale drum as angle transducers. One of them gives a signal for speed, the other is connected to the repeater pointer. The bridge telegraph also has contact functions for logic circuits for the desired direction of rotation. The order repeater indicates the set speed on the telegraph. It has a long pointer which shows the order given and a short reply pointer. The group unit contains units for power supply, indication and control. The control system is housed in aluminium boxes, which give maximum protection from oil, dust and water.

The servomechanism has the following main components:

• a driving unit, which consists of a three-phase motor and an electromagnetic gear-box;

• a position transducer, which is a part of the position servo;

• a position sensing device for control of the acceleration of the main engine.

The tachogenerator measures the speed of the main engine for control of the starting sequence.

WORDS AND EXPRESSIONS:

without manual intervention — без ручного вмешательства

to act as a reference transmitter — действовать как контрольный преобразователь

alterations of the speed— изменения скорости

to set up to meet the requirements — устанавливать, чтобы удовлетворять требованиям

with respect to — по отношению к

alarm buzzer — ревун

angle transducer — угловой преобразователь

short reply pointer — короткий ответный указатель

driving unit — приводящий механизм

electro-magnetic gear-box — электромагнитный редуктор

position transducer — позиционный преобразователь

position sensing device — позиционный чувствительный элемент, устрой

starting sequence — последовательность пусков

Exercise 3. Give the Russian equivalents:

bridge control system, main Diesel engines, bridge telegraph, manual intervention, unmanned engine-room, standardized units, operational reliability, easy installation, spare parts, reference transmitter, propeller speed, to meet the requirements, in some cases, speed reduction, logic circuits, group unit, injection of the starting air, positioning of the camshaft, fuel injection, power level, mechanical actuators, control panel alarm buzzer, order repeater, alarm bell, power supply, scale drum, angle transducer, direction of rotation, set speed, reply pointer, driving unit three-phase motor, electro-magnetic gear-box, position transducer, position servo, position sensing device, starting sequence.

Exercise 4. Translate into English.

1. Управление главными двигателями осуществляется с мости­ка. 2. Эта система используется на судах с машинным отделением без обслуживающего персонала. 3. Стандартные узлы и надежность в работе характерны для этой системы. 4. Легкость установки и не­большое число запчастей характерны для этой системы управления. 5. Пуск и реверс главного двигателя обеспечиваются логическими цепями.

Exercise 5. Give the translation to this abstract.