November 2020 – IMU NOTES

November 29, 2020November 29, 2020

BRIDGE EQUIPMENT – NAVTEX.

ABOUT

NAVTEX (NAVigational TEleX), It is a type of one communication system where we only receive navigational warnings sent by the Navtex station.
NAVTEX was developed to provide information at low cost fortunately there is no user fees associated with receiving NAVTEX broadcasts.

REQUIREMENT

Navtex is part of GMDSS equipment which is required to be fitted onboard every ship as per SOLAS Chapter IV Reg 7.

FREQUENCY

The international navtex frequency is 518 kHz, and these broadcasts should always be in English. National transmission (Generally in local Language)of navtex uses 490 kHz.

LIST OF NAVTEX STATIONS

The world is divided into 16 areas + 5 areas recently introduced for the Arctic region.

Navarea 1 – North Atlantic, North Sea, Baltic Sea
Navarea 2 – East Atlantic
Navarea 3 – Mediterranean Sea
Navarea 4 – West Atlantic
Navarea 5 – Brasil
Navarea 6 – Argentina, Uruguay
Navarea 7 – South Africa
Navarea 8 – India
Navarea 9 – Arabia
Navarea 10 – Australia
Navarea 11 – East Asia
Navarea 12 – Eastern Pacific
Navarea 13 – Russia
Navarea 14 – New Zealand, Southern Pacific
Navarea 15 – Chile
Navarea 16 – Peru
+ 5 areas recently introduced for the Arctic region

Navtex Message text screen

FORMAT OF MESSAGE

November 25, 2020November 25, 2020

What’s the difference between waves and swell?

A lot many people are confused between waves and swell. Waves are generated by the wind moving over the water, Faster the wind bigger is the wave and the direction is the same as the wind. Whereas Swell is created due to the difference in the atmospheric pressure. Swell usually has a smooth top. Swell moves beyond the area they are created but waves are bound to the particular area.

November 12, 2020November 12, 2020

Work on board a Container vessel for Deck Cadet and Crew.

With the term crew we are here talking about the deck department and crew side deck department includes –

Bosun
AB (Able sea man)
OS (ordinary Seaman)
Trainee OS (Trainee Ordinary seaman)

Where Cadet is a Junior Officer he is also involved in maintenance work with rest of the crew. So we will here be focusing only on days work. As you all know Cadet is involved in almost everything he is assisting Chief officer, 3 rd officer keeping watch etc so we will cover this in some other post.

DAYS WORK

The day for OS and Trainee OS

0600-0700 Cleaning ( Accommodation cleaning )
0700-0800 Breakfast
0800-1000 Work
1000 – 1030 Tea Break
1030 – 1200 Work
1200 – 1300 Lunch Break
1300 – 1500 Work
1500 – 1530 Tea Break
1530 – 1730 Work
************************ Do what ever you want ***********************

The day for AB and BOSUN **

800-1000 Work
1000 – 1030 Tea Break
1030 – 1200 Work
1200 – 1300 Lunch Break
1300 – 1500 Work
1500 – 1530 Tea Break
1530 – 1730 Work
************************ Do what ever you want ***********************

** In case of able seaman they will keep watch also and they will get rest accordingly. The Above time table is if they are not keeping watch then this will be the default schedule. For example at anchor. If you want to know in more detail please comment below.

So Now lets come to what are the works CREW do onboard, They have to know everything and should be able to do whatever required as we have limited number of people onboard. Works like Chipping, Painting, Plumbing, High pressure washing etc.

Work Onboard

1. Maintenance of monorail.

Chipping if required and then painted, If some parts require graeasing that is also done.

2. Maintenance of Lashing Bridge

3. Buffing of Foundation bolt .

November 9, 2020November 9, 2020

Gangway

The gangway means the narrow passages used to board or disembark ships. It is named gang as when the vessel is alongside the shore gang uses this passage to board the vessel. The gangway is also considered one of the most critical equipment, as when at the shore we will have high tide and low tide so it is necessary to adjust the gangway accordingly. Even in case if a boat is coming alongside for crew change or maybe some other purpose sometimes the boat might damage the gangway.

November 8, 2020November 8, 2020

Various steps taken by IMO to control pollution.

It is estimated that approximately 706 million gallons of waste oil enter the ocean every year. With this, we can imagine the extent of pollution, Oil tankers transport some 3 Billion tonnes of crude oil and oil products every year around the world by sea.

Now coming to the main question – Various steps taken by IMO to control pollution.

Measures introduced by IMO have helped ensure that the majority of oil tankers are safely built and operated and are constructed to reduce the amount of oil spilled in the event of an accident. Operational pollution, such as from routine tank cleaning operations, has also been cut.

Marpol one of the most important regulation came in force in 1983, have been a success. Statistics from reputable industry and independent bodies showing that these regulations, along with other safety-related regulations such as the introduction of mandatory traffic separation schemes and international standards for seafarer training, have been instrumental in the continuous decline of accidental oil pollution that has taken place over the last 30 years.

Through Marpol IMO introduced a number of radically new concepts,The requirement for new oil tankers to be fitted with segregated ballast tanks.

As far as operational oil pollution is concerned, the many innovations introduced by MARPOL on allowable discharges of bilge water through the oily water separator (with the well-known 15ppm standard), or oily waters from the cargo tanks, through the oil discharge and monitoring system, have contributed greatly to a noticeable decrease in the pollution of the world’s seas.

November 4, 2020January 5, 2021

Everything About Life Raft, HRU and Requirements.

Life rafts are provided in addition to lifeboats on all the ships. They can be launched manually or even automatically when submerged in water with the help of HRU (hydrostatic release unit). Life rafts are stored in a fiberglass container, incorporated with a high-pressure gas used for inflating life raft at the time of emergency.

Requirements

Liferafts should be stowed in such so as to permit the manual release of one raft or container at a time from the securing arrangements.
All liferaft provided on ships should be stowed with its painter permanently attached to strong point on the ship.
Liferaft should inflate automatically when the ship sinks. (we will talk about this later in this post)
Liferafts intended for throw-overboard launching should be stowed so as to be readily transferable for launching on either side of the ship.
Liferafts shall be so constructed so that it can withstand nature for 30 days in all sea conditions.
Liferafts shall be constructed so that it can be droped from a min height of 18m and works satisfatory. Maximum height depends on the place it is stowed.
It shall be provided by means of maunting SART at a height at least 1m above sea level.

What is Hydrostatic release unit (HRU)

The black cylinder in the above image is a HRU. When HRU is submerged in water by 4 m it will automatically cut the rope and liferaft is free to float clear to the surface.

IMUNOTES.IN What is Hydrostatic release unit (HRU)

HRUs may be either of the disposable type, in which case they are replaced every 2-4 years, or they can be of the type that has an unlimited life provided they are serviced and tested.

LIFE RAFT LOCATIONS

On a 399.98m long container vessel, We had 12 liferafts –

2 Each Side Forward of accomodation.
2 Each Side on boat deck.
2 Each Side Aft of accomodation.

Read more about HRU source –
https://www.wartsila.com/

November 3, 2020November 3, 2020

SOLAS Requirements for Lifeboats

SOLAS REQUIREMENT FOR LIFEBOATS.

The number of people onboard determines the capacity of the lifeboat, The lifeboat must be able to accommodate at least 125% of the number of crew and passenger.
Every ship shall carry at least 2 lifeboats.
The lifeboat of a cargo ship with 20,000 GT must be capable of launching when the ship’s speed is at 5 knots.
The ship must carry a minimum of one rescue boat for rescue purposes in addition to the number of lifeboats. If more than one lifeboat is present onboard the ship, one of them can be designated as a rescue boat.
The gravity davits must be held and slid down the lifeboat even when the ship is heeled at an angle of 15 degrees on either side. Ropes called gripes are used to hold the lifeboat with the cradle in the stowed position.
The lifeboat should not descend at more than a speed of 0.6m/s or 36m/min. This speed is generally controlled by centrifugal brakes.
The Lifeboats are to be painted with an internationally-approved bright orange color and the ship’s call sign is to be printed on it.

WHAT’S INSIDE A LIFEBOAT

Magnetic Compass

The magnetic compass is important when navigating we will talk about this later in some other article – why we need a magnetic compass when we already have a gyrocompass. whenever we enter a lifeboat we compare the heading of the magnetic compass on the lifeboat with that on the bridge.

Food Rations and water.

Radar Reflector.

Labeled cup

Fishing tackle.

Day Signaling Mirror

Waterproof Torch.

November 3, 2020November 3, 2020

Bilge alarm testing onboard.

Onboard a container vessel we used to check all the bilge alarms every month and it was recorded with the chief officer’s signature near the bilge alarm and pumping out pannel.

When a bilge alarm comes we used to get the Alarm on Bridge and Ships office on some ships it can be in CCR. The panel looks different on different vessel. Look at a sample we found onboard a container vessel.

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The above image is panel for bilge alarm and pumping out arrangement. Once bilge alarm testing is complete our pannel will look something like the image below.