How are Generators Synchronized on a Ship?

                        Synchronization of generators is an activity that is carried out quite often on ship. It is a prerequisite that each and every engineer on the ship knows the procedure thoroughly. In emergencies, the engineers are required to carry out the process manually in extremely limited amount of time.

Introduction

                  It's a known fact that marine generators are the heart of any type of ship. Maritime law requires that every ship should have at least two generators. Nowadays all the ships have around 2-3 generators on board. More number of generators are used to facilitate load sharing and to prevent wear down due to excessive load.
             Maintenance of generators at regular interval of time is extremely important. In this article we will learn the process of generator synchronization when multiple machines are required or one of the generators needs to the stopped and the other started in its place
Say for example if a ship has three generators on board, two are used under normal working conditions and one is kept as stand-by.                  
              Whenever a requirement to service a running generator arises , the standby generator is brought in line and the desired generator is taken off line. For bringing the standby generator in line, the generator is synchronised with the other running generators.

The main things that are kept in check for synchronizing a generator are :

• Frequency
• Voltage
• Load
• Phase

Let's have a look how the synchonization of generators is done manually

Generator Synchronization Procedure- Before starting

A step by step method for synchronizing generators in provided below.

1. When a decision of synchronizing generators in taken, first the bridge should be notified about the scheduled activity
2. Start the generator that has to be synchronized. Before starting, prime the engine with fuel using hand pump. Make sure the engine block heater is turned off.
3. Open the air valve and then turn on the engine.
4. Once the engine starts, check if the oil pressure and cooling water pressure is adequate. Check if the cooling water pump is working properly by feeling the pipes. Once the check is done, close the air valves.

Synchronizing procedure

Once the engine starts running properly, synchronization is carried out.

1. In the Engine control room, Check the pressure gauges.
2. On the generator control panel, check if all the ground lights are working properly with adequate brightness.
3. Also check the synchronizing relays for open position. Bring the running or the lead generator to the desired optimum parameters: 480 volts and 60 hertz
4. Bring the generator that is to be synchronized(0n-coming) to the desired parameters. Now turn on the synchronizing relay and keep a close look at the needle.
5. The needle in the synchroscope will move at a varying speed initially. Adjust the speed of the generator by obtaining a steady slow motion of the needle in the clock wise direction.
6. Once the needle is moving at a steady speed, depress the breaker close button when the needle has traveled three-fourth of its way. Energize the breakers when the needle reaches a position similar to the 11' o clock position of a clock.
7. After doing this, check the parameters of the on-coming generator. They should be same as those of the leading generator. i.e 480 Volts and 60 hertz

 

 

 

After synchronizing

After the main job of synchronizing, the following steps are to be carried out.

1. Change the governer control to the off-going generator.
2. Now the load shown in the guages by this generator should be removed off the system as soon as possible before it starts acting as load(reverse power). This can be done by quickly pulling the trip breaker as soon as the generator goes off-line.
3. Once the generator is offline, stop the engine using a toggle switch.
4. After turning off the engine, turn on the engine block heater.
5. At the end, take a proper look at the control panel guages for adequate pressure and even distrubution of load.

           It must also be noted that load distribution can be adjusted by varying the fuel supply to the generator via its governor but for current sharing to be equal you would need to vary the excitation current which changes the power factor of the generator.

Image Credits

http://powergenelectrics.com/yahoo_site_admin/assets/images/synchroscope_2.291110319_std.jpg
http://www.seg-me.com/UNATRAC%20Project1.jpg
http://www.o-t-s.com/synchroscope.jpg

How to Avoid Food Poisoning in Ships

                             Hi blog readers,here i have listed the ways to avoid food poisoning onboard the vessel along with some video links...read and forward.....

                    Incidents of food poisoning in ships are not a surprise. Recently on January 08, at least 340 passengers of MSC Sinfonia, docked in Salvador, Bahia suffered severe vomiting and diarrhea. It was reported that an inspection found problems with the amount of chlorine in the ship’s drinking water and with the storage of some perishable food items, notably mayonnaise.
Ensuring food safety onboard is a team effort and here are some tips to avoid food poisoning in ships:





Storing

• Check goods before taking onboard
  • Source of supply: to be from approved vendors/brands
  • Check for expiry date
  • Do not accept damaged or open packages
  • Inspect frozen goods: to be inhard frozen state
  • Store frozen and chilled goods first
  • Do not store rotten vegetables and fruits
  • Follow FIFO (First In First Out) for using
  • Cold/Cool rooms: Check temperatures regularly and report problems if any
  • Cold/Cool rooms: Check indication lights are working and door seals on closure
  • Cold/Cool rooms: Check internal safety alarms, opening mechanisms operation
  • Use protective clothing to enter cold rooms and freezers
  • Carry goods safely

Food Handling

• Galley
  • Food contact areas to be kept clean, use right detergents
  • Keep work tops and cooking utensils clean and disinfected
  • Disinfect raw meat,fish cutting boards after use
  • Keep clean: Deck, bulk head, ventilation ducts
  • Secure cleaning gear in the right place after use
  • Follow housekeeping
•  
• Personal hygiene of Food Handlers
  • Wash your hands with soap in hot running water before you handle food
  • Dry your hands in single use towels or air dryer
  • Trim your nails
  • Be medically fit
  • Wash your hands again after you handle raw meat,poultry,fish
•  
• Water quality
  • Polluted or contaminated water may taste same, but if used causes sickness
  • Boil water before you use
  • Regularly flush taps that are not in constant use
  • Maintain a log
•  
• Storing prepared food
  • Store at temperature 8 degree Celsius or less, or 63 or higher
  • Do not expose food items for more than two hours in 8 to 63 degree Celsius
  • Ensure food storing place is free from rats and other insects

Personal Hygiene

• Wash your hands
  • before you eat
  • after you eat, drink, smoke
  • after using rest room
  • after blowing your nose
•  
• Do not eat if you find your food abnormal in terms of taste, smell, color or if there is dirt or foreign objects
•  
• Before you sip directly bottled drinks or cans, wash the bottles or cans

Here are some interesting video clips on Basic Food Safety and Foodborne Illnesses

• Part 1 of 6: Introduction to Safe Food Handling
• Part 2 of 6: Holding Time and Temperatures
• Part 3 of 6: Poor Personal Hygiene
• Part 4 of 6: Inadequate Cooking and Contaminated Equipment
• Part 5 of 6: Adulterated Food
• Part 6 of 6: Review
•                     Bye readers....keep reading my blog......

The Engine Room

                           The Engine Room

Here is the poem on Engine Room.....unknown author edited by me......


The sparkling triple expansion,
With its noise and whistling steam
The thumpity thump of the crankshaft,
And the connecting rods all agleam.
The clickity clack of the valve gear,
And the swish of the feed water rams,
The aroma of engine lubricants,
The sound of the oilman's salaams.

The whir from the boiler air fan,
The condenser's different smell,
The leaking steam from loose packing,
The gurgle from the bilge box well.

The sudden blast from the boiler room,
As the junior blows the glass,
The aroma of sweat and brasso,
As the fireman cleans the brass.

The startling ring of the telegraph,
And the action that it brings,
The harmony of disciplined colleagues,
Like music at it swings.

Sunlight streaming through skylights,
Dazzling on polished steel,
Moving around the engine room,
As the quartermaster moves the wheel.

The slowing down of the engines,
And the final telegraph sound,
The quietness of finished with engines,
The joy of homeward bound.

"MV Solitaire"of All Seas is the largest pipelay vessel in the world.

Some interesting features of MV Solitaire are:

• has a pipe carrying capacity of 22000 t.
• maneuvers with full dynamic positioning to work safely in congested areas.
• operational since 1998.
• has a lay speed of over 9 km a day with in-house Phoenix automatic welding system.
• has a deepwater pipelay record of 2775 m (9100’).
• after modifications in 2005, now with a holding force of 1050 t can lay the heaviest pipelines.

Here is a photograph of MV Solitaire, from All Seas.


             

View amazing video clips of operations onboard MV Solitaire:
 Part 1 and 
Part 2.

Centrifugal Oil Purifiers - Starting and Stopping Procedures

Centrifugal Oil Purifiers - Starting and Stopping Procedures

               We have already know about the basic principle of operation of purifiers...! Lets know how to start and stop purifiers.., necessary safety precautions before starting, de-sludging procedure, and emergency stopping....etc.....!

Recap...!

We all know that centrifuges are an important type of auxiliary equipment on board ships and that they are classified into two operating functions.
      
      One is Clarifier, which seperates solids from liquids.
      Other type is a Purifier, which seperates liquids of different density.  

The Purifier operates on the principle of seperation by centrifugal force. But in order to optimize the purification process, certain parameters should be adjusted before purifier is started. Out of those parameters, very important parameters are...

1. Feed inlet oil temperature, 
2. Density of Oil, 
3. R.P.M of the rotating bowl,
 4. Back Pressure, 
5. Throughput of oil feed.

Insight Of the Parameters...!

1. Feed inlet oil temperature: Before entering the purifier, the dirty oil passes through the heater, which increases the temperature, thus reducing the viscosity of the oil to be purified. The lower the viscosity, the better will be the purification.

2. Density of Oil: As the dirty oil entering the purifier is heated to reduce the viscosity, the density also reduces. The lower the density, better the seperation.

3. R.P.M of the rotating bowl: If the purifier has not achieved full rpm(revolutions per second), then the centrifugal force will not be sufficient enough to aid the seperation.

4. Back Pressure: The back pressure should be adjusted after the purifier is started. The back pressure varies as the temperature, density, viscosity of feed oil inlet varies. The back pressure ensures that the oil paring disc is immersed in the clean oil on the way of pumping to the clean oil tank.

5. Throughput of oil feed: Throughput means the quantity of oil pumped into the purifier/hr. In order to optimize the purification, the throughput must be minimum.

Pre-checks before starting a Purifier...!

Before starting a Purifier, following checks are very essential:

1. If the Purifier is started after a overhaul, then check all fittings are fiited in right manner. The bowl frame hood locked with hinges.

2. Check the Oil level in the gear case. Ensure that it is exactly half in the sight glass. Also ensure the sight glass is in vertical position, as there is a common mistake of fixing it in horizontal position.

3. check the direction of rotation of the seperator, by just starting and stopping the purifier motor.

4. Check whether the brake is in released position.

Starting a Purifier...!

1. Ensure the lines are set and respective valves are open. Usually the lines are set from settling tank to service tank.

2. Start the purifier feed pump with the 3-way re-circulation valve in a position leading to settling tank.

3. Open the steam to the heater slightly ensuring the drains are open so that the condensate drains. close the drains once steam appears.

4. Start the Purifier.

5. Check for vibrations, check the gear case for noise and abnormal heating.

6. Note the current (amps) during starting. It goes high during starting and then when the purifier bowl 
picks-up speed & when it reaches the rated speed, the current drawn drops to normal value.

7. Ensure the feed inlet temperature has reached optimum temperature for seperation as stated in the Bunker report & nomogram ( bunker delivery note gives the density of the fuel and using this we can get the seperation temperature and gravity disc size from the nomogram)

8. Now check whether the bowl has reached the rated speed by looking at the revolution counter. The revolution counter gives the scaled down speed of the bowl. The ratio for calculation can be obtained from the manual.

9. Now, after the bowl reaching the rated rpm, check for current attaining its normal value.

De-sludge procedure:

10. Open the Bowl closing water/Operating water, which closes the bowl. (Ensure sufficient water is present in the operating water tank)

11. Now after 10 seconds, open the sealing water to the bowl.

12. The sealing water should be kept open till the water comes out of the waste water outlet.

13. Once the water overflows throught the waste water outlet, stop the sealing water.

14. Now open the de-sludge water/bowl opening water. (this is done to ensure the bowl has closed properly). During de-sludge we can hear a characteristic sound by the opening of the bowl.

15. Repeat the steps 10, 11 ,12 & 13.

16. Open the 3-way re-circulation valve such that the dirty oil feed is fed into the purifier.

17. Wait for the back pressure to build up.

18. Check for overflowing of dirty-oil through waste water outlet & sludge port.

19. Now adjust the throughput to a value specified in the manual. Correspondingly adjust the back pressure too.

20. Now the purifier is put into operation. Change over the clean-oil filling valve to service tank.

After-checks & stopping of purifier...!

Checks after starting the purifier during regular watches:

1. Adjust the throughput, back pressure, temperature of feed inlet if necessary

2. gear case oil level, motor amps, general leakages, vibration have to be monitored

3. De-sludge every 2 hours for heavy oil purifiers & every 4 hours for lubricating oil purifiers.( refer manual or chief engineer instructions)

Stopping of Purifiers:

1. De-sludge the purifier after stopping the feed inlet.

2. shut down the steam inlet to the oil.

3. Stop the purifier after filling up the bowl with water.

4. Apply brakes and bring up the purifier to complete rest.

5. If any emergency, the purifiers has emergency stops, on pressing it, will stop the purifiers immediately shutting off the feed.
                                        
       Thus we have seen in detail how to start the purifier after carrying out all safety checks and we have also seen how to stop it...! But today the system is of ALCAP and much more......

The engineer and the mate

 I have posted not to show who is great or not...just for the poem......

Oil soaked shoes all covered with grime;
Polished shoes with a brilliant shine,

Sweated clothes all stained with grease;
Shirt and tie and pants well creased,

Oily scarred and calloused hands
Manicured fingers, looking grand.

Thus they approached the pearly gates,
The Engineer and the Mate.

Saint Peter gazed at this strange sight;
He knew one was wrong, the other was right,

To be sure, he then did look
In his gigantic secret judgment book

Then looking up he said so clear
I'll now pass judgment on the Engineer.

You've sweated blood, you breathed some gas
The scars and bruises and burns still last.

So come my son and take your place
Like a king, in all his grace.

My son you've stood it very well -
You've surely had your share of hell.

The Engineer passed through the gates;
Saint Peter then turned unto the Mate.

You've filled your lungs with cool clean air;
You've known the breezes and the sun up there,

Pushing a pencil, you've traveled in class;
You've been a passenger before the mast.

There isn't a question, yes or no -
Now it's your turn to go below!!

  unknown author....edited by me....

People on the ship and what do they do ?

Below is a brief description of various positions on a typical - larger vessel. This is given as an overall view there may be more or less people depending on the type of vessel and companies.......

                                               

DECK DEPARTMENT:

                     

Master (Captain) - In command of vessel and all of its departments, in most cases a pencil pushing job doing the payroll, ships paperwork, only on bridge for entry and departure of ports and to check on navigational watches. Almost always a day worker.
Chief Mate - Directly supervises Bosun, 2nd and 3rd Mates during all deck evolutions (cargo/maintenance/repairs/drills), on most ships also stands a navigation watch. Traditionally the Chief Mate was a day worker, but more recently a watch standee as more and more positions are eliminated from ships he has been made into a watch standee.
Second Mate - Responsible for all aspects navigation (voyage planning, chart/publication correction, navigation equipment maintenance, and recently added GMDSS Communications responsibilities as well) while at sea, in charge of cargo watch while in port for the safe and efficient transfer of cargo. Usually a watch standee.
Third Mate - Responsible for all safety inspections, usually designated as medical officer, maintains navigation watch while at sea, in charge of cargo watch while in port. Usually a watch standee.
Deck Cadet - A student from one of the Maritime Academies doing a sea apprenticeship to become a Third Mate. Entry Level
Bosun / Boatswain - Highest unlicensed rating that supervises all A/B's during deck maintenance and repair. Usually a day worker.
Able Bodied Seaman (A/B) / Leading Seaman / Quartermaster - While on navigation watch under the supervision of the mate on watch, responsible for keeping a lookout (for other vessels, land masses, etc.) and steering the vessel in and out of port. Deck maintenance primarily include chipping rust, painting, lubricating fittings, cleaning various areas, and splicing line. Usually a watch standee.
Ordinary Seaman (O/S) - Same as A/B with no steering, and heavier concentration on cleaning. If a vessel carries O/S's they are usually watch standees. Entry Level

ENGINE DEPARTMENT:

                      

                  

Chief Engineer - In charge of the Engine Department, responsible for most paperwork, ordering, maintaining spare parts inventory, and directly supervises critical engine repairs. Almost always a day worker.
1st Assistant Engineer - Is in charge of all engine room repairs and maintenance. Maintains overtime records. Can either be a watch standee or day worker for the same reasons as a Chief Mate.
2nd Assistant Engineer - Maintains an engine room watch and is responsible for the smooth operation of all engine room system. Also performs system checks on engine room systems. Usually a watch standee
3rd Assistant Engineer - Maintains an engine room watch and is responsible for the smooth operation of all engine room system. Usually a watch standee
4th Assistant Engineer - Maintains an engine room watch and is responsible for the smooth operation of all engine room system. Usually a watch standee
Engine Cadet - A student from one of the Maritime Academies doing a sea apprenticeship to become a Third Assistant Engineer. Entry Level
Electrician - Responsible for anything on ship's electrical system. Usually a day worker.
Mechanic - Responsible for the taking apart of machinery and their repairs, usually under the supervision of the day engineer. Normally the most senior rating.
DEMAC / QMED / Motorman - Make Rounds in Engine Room and report to Engineer on watch, assist as directed. Can either be a watch standee or day worker.
Oiler / UJE (Unlicensed Jr. Engineer) - Make rounds, clean, assist as directed. Usually a watch standee. Can either be a watch standee or day worker.
Wiper - Responsible for cleaning various engine spaces, and to assist as directed. Can either be a watch standee or day worker. Entry Level

STEWARD DEPARTMENT:

                                  

                                   

Chief Steward/Baker - In charge of steward department, creates daily menus, orders and stock sufficient amounts of food for voyage, cooks, bakes, and prepares food.
Chief Cook - Cooks, bakes and prepare food.
Assistant Cook - Cooks, bakes and prepare food.
GSU/BR (General Steward Utility/Bedroom) - Responsible for cleaning officer's staterooms, and also cleaning of galley areas around meal hours. Entry Level.