Laman

Minggu, 17 Februari 2013

Watchkeeping and equipment Operation


Watchkeeping and equipment Operation

The’ round the clock' operation of a ship at sea requires a rota system of attendance in the machinery space. This has developed into a system of watchkeeping that has endured until recently. The arrival of 'Unattended Machinery Spaces' (UMS) has begun to erode this traditional practice of watchkeeping. The organisation of the Engineering Department, conventional watchkeeping and UMS practices will now be outlined.
The Engineering Department
The Chief Engineer is directly responsible to the Master for the satisfactory operation of all machinery and equipment. Apart from assuming all responsibility his role is mainly that of consultant and adviser. It is not usual for the Chief Engineer to keep a watch.
The Second Engineer is responsible for the practical upkeep of machinery and the manning of the engine room: he is in effect an executive officer. On some ships the Second Engineer may keep a watch.
The Third and Fourth Engineers are usually senior watchkeepers or engineers in charge of a watch. Each may have particular areas of responsibility, such as generators or boilers.
Fifth and Sixth Engineers may be referred to as such, or all below Fourth Engineer may be classed as Junior Engineers. They will make up as additional watchkeepers, day workers on maintenance work or possibly act as Refrigeration Engineer.
Electrical Engineers may be carried on large ships or where company practice dictates. Where no specialist Electrical Engineer is carried the duty will fall on one of the engineers. Various engine room ratings will usually form part of the engine room complement. Donkeymen are usually senior ratings who attend the auxiliary boiler while the ship is in port. Otherwise they will direct the ratings in the maintenance and upkeep of the machinery space. A storekeeper may also be carried and on tankers a pump man is employed to maintain and operate the cargo pumps. The engine room ratings, e.g. firemen, greasers, etc., are usually employed on watches to assist the engineer in charge.
The watchkeeping system
The system of watches adopted on board ship is usually a four hour period of working with eight hours rest for the members of each watch. The three watches in any 12 hour period are usually 12-4, 4—8 and 8-12. The word 'watch' is taken as meaning the time period and also the personnel at work during that period. The watchkeeping arrangements and the make up of the watch will be decided by the Chief Engineer. Factors to be taken into account in this matter will include the type of ship, the type of machinery and degree of automation, the qualifications and experience of the members of the watch, any special conditions such as weather, ship location, international and local regulations, etc. The engineer officer in charge of the watch is the Chief Engineer's representative and is responsible for the safe and efficient operation and upkeep of all machinery affecting the safety of
the ship.
Operating the watch
An engineer officer in charge, with perhaps a junior engineer assisting and one or more ratings, will form the watch. Each member of the watch should be familiar with his duties and the safety and survival equipment in the machinery space. This would include a knowledge of the fire fighting equipment with respect to location and operation, being able to distinguish the different alarms and the action required, an understanding of the communications systems and how to summon help and also being aware of the escape routes from the machinery space. At the beginning of the watch the current operational parameters and the condition of all machinery should be verified and also the log
readings should correspond with those observed. The engineer officer in charge should note if there are any special orders or instructions relating to the operation of the main machinery or auxiliaries. He
should determine what work is in progress and any hazards or limitations this presents. The levels of tanks containing fuel, water, slops, ballast, etc., should be noted and also the level of the various bilges. The operating mode of equipment and available standby equipment should also be noted.
 At appropriate intervals inspections should be made of the main propulsion plant, auxiliary machinery and steering gear spaces. Any routine adjustments may then be made and malfunctions or breakdowns can be noted, reported and corrected. During these tours of inspection bilge levels should be noted, piping and systems observed for leaks, and local indicating instruments can be observed.
Where bilge levels are high, or the well is full, it must be pumped dry. The liquid will be pumped to an oily water separator, and only clean water is to be discharged overboard. Particular attention must be paid to the relevant oil pollution regulations both of a national and international nature, depending upon the location of the ship. Bilges should not be pumped when in port. Oily bilges are usually emptied to a slop tank from which the oil may be reclaimed or discharged into suitable facilities
when in port. The discharging of oil from a ship usually results in the engineer responsible and the master being arrested. Bridge orders must be promptly carried out and a record of any required changes in speed and direction should be kept. When under standby or manceuvring conditions with the machinery being manually operated the control unit or console should be continuously manned.
Certain watchkeeping duties will be necessary for the continuous operation of equipment or plant—the transferring of fuel for instance. In addition to these regular tasks other repair or maintenance tasks may be required of the watchkeeping personnel. However no tasks should be set or undertaken which will interfere with the supervisory duties relating to the main machinery and associated equipment.
During the watch a log or record will be taken of the various parameters of main and auxiliary equipment. This may be a manual operation or provided automatically on modern vessels by a data logger. A typical log book page for a slow-speed diesel driven vessel is shown in Figure 17.1. ( belum ada gambar )
The hours and minutes columns are necessary since a ship, passing through time zones, may have watches of more or less than four hours. Fuel consumption figures are used to determine the efficiency of operation, in addition to providing a check on the available bunker quantities. Lubricating oil tank levels and consumption to some extent indicate engine oil consumption. The sump level is recorded and checked that it does not rise or fall, but a gradual fall is acceptable as the
engine uses some oil during operation. If the sump level were to rise this would indicate water leakage into the oil and an investigation into the cause must be made. The engine exhaust temperatures should ail read about the same to indicate an equal power production from each cylinder. The various temperature and pressure values for the cooling water and lubricating oil should be at, or near to, the manufacturer's designed values for the particular speed or fuel lever settings. Any high outlet temperature for cooling water would indicate a lack of supply to that point. Various parameters for the main engine turbo-blowers are also logged. Since they are high-speed turbines the correct supply of
lubricating oil is essential. The machine itself is water cooled since it is circulated by hot exhaust gases. The air cooler is used to increase the charge air density to enable a large quantity of air to enter the engine cylinder. If cooling were inadequate a lesser mass of air would be supplied to the engine, resulting in a reduced power output, inefficient combustion and black smoke. Various miscellaneous level and temperature readings are taken of heavy oil tanks, both settling and service, sterntube bearing temperature, sea water temperature, etc. The operating diesel generators will have their exhaust temperatures, cooling water and lubricating oil temperatures and pressures logged in much the same way as for the main engine. Of particular importance will be the log of running hours since
this will be the basis for overhauling the machinery. Other auxiliary machinery and equipment, such as heat exchangers, fresh water generator (evaporator), boiler, air conditioning plant and refrigeration plant will also have appropriate readings taken. There will usually be summaries or daily account tables for heavy oil, diesel oil, lubricating oil and fresh water, which will be compiled at noon. Provision is also made for remarks or important events to be noted in the log for each watch. The completed log is used to compile a summary sheet or abstract of information which is returned to the company head office for record purposes. The log for a medium-speed diesel driven ship would be fairly similar with probably greater numbers of cylinder readings to be taken and often more than one engine. There would also be gearbox parameters to be logged. For a steam turbine driven vessel the main log readings will be for the boiler and the turbine. Boiler steam pressure, combustion air pressure, fuel oil temperatures, etc., will all be recorded. For the turbine the main bearing temperatures, steam pressures and temperatures, condenser vacuum, etc., must be noted. All logged values should correspond fairly closely with the design values for the equipment. Where situations occur in the machinery space which may affect the speed, manoeuvrability, power supply or other essentials for the safe operation of the ship, the bridge should be informed as soon as possible.
This notification should preferably be given before any changes are made to enable the bridge to take appropriate action. The engineer in charge should notify the Chief Engineer in the event of any serious occurrence or a situation where he is unsure of the action to take. Examples might be, if any machinery suffers severe damage, or a malfunction occurs which may lead to serious damage. However where immediate action is necessary to ensure safety of the ship, its machinery and crew, it must be taken by the engineer in charge. At the completion of the watch each member should hand over to his relief, ensuring that he is competent to take over and carry out his duties effectively.
UMS operation
The machinery spaces will usually be manned at least eight hours per day. During this time the engineers will be undertaking various maintenance tasks, the duty engineer having particular responsibility for the watchkeeping duties and dealing with any alarms which may occur. When operating unmanned anyone entering the machinery space must inform the deck officer on watch. When working, or making a tour of  inspection alone, the deck officer on watch should be telephoned at agreed intervals of perhaps 15 or 30 minutes. Where the machinery space is unattended, a duty engineer will be responsible for supervision. He will normally be one of three senior watchkeeping engineers and will work on a 24 hour on, 48 hours off  rota. During his rota period he will make tours of inspection about every four hours beginning at 7 or 8 o'clock in the morning. The tour of inspection will be similar to that for a conventional watch with due consideration being given to the unattended mode of machinery operation. Trends in parameter readings must be observed, and any instability in operating conditions must be rectified, etc. A set list or mini-log of readings may have to be taken during the various tours. Between tours of inspection the Duty Engineer will be on call and should be ready to investigate any alarms relayed to his cabin or the various public rooms. The Duty Engineer should not be out of range of these alarms without appointing a relief and informing the bridge.
The main log book readings will be taken as required while on a tour of inspection. The various regular duties, such as fuel transfer, pumping of bilges, and so on, should be carried out during the daywork period, but it remains the responsibility of the Duty Engineer to ensure that they
are done.
Bunkering
The loading of fuel oil into a ship's tanks from a shoreside installation or
bunker barge takes place about once a trip. The penalties for oil spills
are large, the damage to the environment is considerable, and the ship
may well be delayed or even arrested if this job is not properly carried
out.
Bynkering is traditionally the fourth engineer's job. He will usually be
assisted by at least one other engineer and one or more ratings. Most
ships will have a set procedure which is to be followed or some form of
general instructions which might include:
1. AH scuppers are to be sealed off, i.e. plugged, to prevent any minor
oil spill on deck going overboard.
2. All tank air vent containments or drip trays are to be sealed or
plugged.
3. Sawdust should be available at the bunkering station and various
positions around the deck.
4. All fuel tank valves should be carefully checked before bunkering
commences. The personnel involved should be quite familiar with
the piping systems, tank valves, spill tanks and all tank-sounding
equipment.
5. All valves on tanks which are not to be used should be closed or
switched to the 'off position and effectively safeguarded against
opening or operation.
6. Any manual valves in the filling lines should be proved to be open
for the flow of liquid.
7. Proven, reliable tank-sounding equipment must be used to regularly
check the contents of each tank. It may even be necessary to 'dip' or
manually sound tanks to be certain of their contents.
8. A complete set of all tank soundings must be obtained before
bunkering commences.
9. A suitable means of communication must be set up between the ship
and the bunkering installation before bunkering commences.
10. On-board communication between involved personnel should be by
hand radio sets or some other satisfactory means.
11. Any tank that is filling should be identified in some way on the level
indicator, possibly by a sign or marker reading 'FILLING'.
12. In the event of a spill, the Port Authorities should be informed as
soon as possible to enable appropriate cleaning measures to be
taken.
Periodic safety routines
In addition to watchkeeping and maintenance duties, various safety and
emergency equipment must be periodically checked. As an example, the
following inspections should take place at least weekly:
348 Watchkeeping and equipment operation
1. Emergency generator should be started and run for a reasonable
period. Fuel oil, lubricating oil and cooling water supplies and tank
levels should be checked.
2. Emergency fire pump should be run and the deck fire main
operated for a reasonable period. AH operating parameters should
be checked.
3. Carbon dioxide cylinder storage room should be visually examined.
The release box door should be opened to test the alarm and check
that the machinery-space fans stop.
4. One smoke detector in each circuit should be tested to ensure
operation and correct indication on the alarm panel. Aerosol test
sprays are available to safely check some types of detector.
5. Fire pushbutton alarms should be tested, by operating a different
one during each test.
6. Any machinery space ventilators or skylights should be operated
and greased, if necessary, to ensure smooth, rapid closing should
this be necessary.
7. Fire extinguishers should be observed in their correct location and
checked to ensure they are operable.
8. Fire hoses and nozzles should likewise be observed in their correct
places. The nozzles should be tried on the hose coupling. Any
defective hose should be replaced.
9. Any emergency batteries, e.g. for lighting or emergency generator
starting, should be examined, have the acid specific gravity checked,
and be topped up, as required.
10. All lifeboat engines should be run for a reasonable period. Fuel oil
and lubricating oil levels should be checked.
11. All valves and equipment operated from the fire control point
should be checked for operation, where this is possible.
12. Any watertight doors should be opened and closed by hand and
power. The guides should be checked to ensure that they are clear
and unobstructed.

1 komentar: