Text C. Side Doors and Loaders
Side door/ramps are available for ro-ro operations and are similar to stern door/ramp installations. Most side door installations, however, are intended for quayside fork lift operations with palletized cargo being loaded onto a platform at the door by the quayside forklift and stowed in the ship by another forklift truck. Instead of a loading platform on ships trading to ports with high tidal ranges a ramp onto which the quayside forklift truck drives may be fitted. Elevator platforms may be fitted immediately inboard of the side door to service various tween decks and the hold. A particular type of elevator system is that developed for the transportation of paper products especially newsprint. The quayside forklift places the newsprint rolls on the height-adjustable loading platform which together with the elevator platform is fitted with roller conveyors. Movement of the roller conveyors is automatic, the newsprint rolls being transferred from the loading platform to the elevator platform which travels to the pre-selected deck or hold level for unloading.
Upward folding doors with hydraulic cylinders actuating the hinge are usually fitted to the side opening, the load platform being fitted inside the door and hinged at the bottom of the opening, automatically being lowered when the door is opened. Combined side door/hatch covers are fitted in designs where the ship is low in the water relative to the height of quay in order to provide sufficient head room for forklift truck operation. With the side port elevator system referred to above a combined door/hatch is fitted to the hatch carrying part of the tower which houses the upper part of the cargo elevator.
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 forengines, 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 ofspare 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 logiccircuitsin 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 характерныдля этой системы управления. 5. Пуск и реверс главного двигателя обеспечиваются логическими цепями.
Exercise 5.Give the translation to this abstract.
AUTOCHIEF
Main Engine Bridge Control
AutoChief III is a main engine bridge control system for single engine plant with fixed propeller. It is designed for engines having extensive pneumatic manoeuvring equipment delivered as part of the engine in order to get the maximum benefit from the engine standard system. Norcontrol speed-set unit controls set point to main engine standard governor. AutoChief III is an electronic-pneumatic system, using electrical signal transmission from bridge to engine room and between sensors and the central unit. Starting, reversing and, speed are controlled directly by a manoeuvring handle on bridge which also has built-in emergency telegraph system. The engine is automatically protected against rough manoeuvring.
The engine-room panel, which is normally located near by existing f manual manoeuvring system, contains necessary test and simulating facilities. The electronic logic isconcentrated on a minimum number of cards, which results in low spare part costs.
Вспомогательные механизмы.
Auxiliaries. PUMPS
Exercise 1. Read and learn the following words and expressions:
| to flow out | вытекать | |
| suction head | высота всасывания | |
| rotation | вращение | |
| rotary | ротационный | |
| arrow | стрелка | |
| acquirement | требование | |
| ammeter | амперметр | |
| to exceed | превышать | |
| single stage | односекционный | |
| rating | расчетная величина | |
| tightness | герметичность, зд: затяжка | |
| packing gland | сальник, уплотнение вала | |
| to trap | захватывать | |
| impeller | крылатка | |
| volute | улитка | |
| output | производительность | |
| plunger | плунжер | |
| discharge head | высота нагнетания | |
| reciprocating | поршневой | |
| screw | винтовой | |
| centrifugal | центробежный | |
| gear | шестерёнчатый | |
| vane | лопастной | |
| axial-plunger | аксиально плунжерный | |
| jet | струйный |
Exercise 2. Read and translate the text
Marine Pumps
On board ship, pumps are used for a number of services. Pumps feed water to the boilers, draw condensate from the condensers, supply sea water to the fire-main, circulate cooling water for the main and auxiliary engines cooling system, coolers and condensers, empty the bilges, transfer fuel oil, pump in and out ballast water, discharge fuel oil to the burners and fuel injection valves, circulate lube oil to bearings and gears of the propulsion plant components.
Every pump has a power end, which may be a steam turbine, a reciprocating engine or an electric motor, and a liquid end where the liquid enters and leaves the pump.
The suction head means the pressure of the liquid entering the pump, or the difference in the level of liquid with respect to the level of the pump on the suction side. The discharge head means the pressure of the liquid leaving the pump, or the level of liquid with respect to the level of the pump on the discharge side.
Most marine pumps are of reciprocating, rotary, centrifugal, or jet type.
The reciprocating pump moves liquid or gas by means of a piston or plunger which goes back and forth or up and down within a cylinder containing a suction valve and a discharge valve. An adjustable relief valve is fitted to the discharge chamber to protect the pump and piping against excessive pressure.
All rotary pumps work by means of rotating parts, which trap the liquid at the suction side and force it through the discharge outlet. Classification of rotary pumps is generally made according to the type of rotating elements: screw, gear, vane, axial-plunger rotary pumps. Rotary pumps are particularly used for pumping oil and other heavy, viscous liquids.
The centrifugal pump utilizes the throwing force of a rapidly revolving impeller. The liquid is drawn in at the center of the impeller and is discharged at the outer rim of the impeller. Centrifugal pumps are widely used on board ship for pumping, no viscous liquids. Fire pumps usually are single stage, double suction, volute type either turbine-driven or motor-driven centrifugal pumps. Main feed pump is a high-speed, multistage, turbine driven, horizontal or vertical pump.
Jet pumps, unlike other types of pumps, use the Venturi effect to move fluid from one location to another, it means that the fluid is drawn into the pump passing through a constricted section. While passing through the constricted section the fluid’s pressure decreases, while the fluids velocity increases resulting in an increase in kinetic energy that allows fluid to flow.
There are many brands and models of jet pumps available, with some models offering pump capacity of up to a thousand gallons per hour. When choosing these pumps, the first thing should be paid attention to is how much water flow is required.
Exercise 3. Answer the following questions:
1. What is the most often used type of pumps in ships? 2. Where are the pumps to be found? 3. What is the function of the pumps? 4. What does the pump consist of? 5. Is it good when the liquid seeps through the packing? 6. Is impeller keyed onto the shaft? 7. How is the shaft protected against liquid? 8. What should be head of the pump be? 9. If the pump does not deliver water, will you check the casing? Should it be full of liquid? 10. What is recommended to do during long standing still periods?
Exercise 4. Give Russian/English equivalents.
· Steam turbine powered vessel; to handle fresh water; vertical shaft unit; pump casing, coupling; suction nozzle and discharge nozzle; secured by means of studs; grease lubricator; operating features; power requirements; discharge chamber; packing;
· высота всасывания, односекционный, лопастный насос, захватывать, набивка, труба, уплотнительное кольцо, заглушка, мощность, приемное сопло, фланец, предотвращать, корпус, муфта, крылатка, вертикальный агрегат.
Exercise 5.Look through the following information and then make the translation of the part B.
Part A.