Magnetic compass

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Image
The magnetic compass is fitted on the upper bridge exactly center line of the ship   It is referred to as standard compass     1. D ry C ard    2. W et C ard   A compass point north because all magnets have two poles north pole, south pole.   The north pole of the one magnet attracted towards the south pole of another magnet     DRY CARD COMPASS   A light aluminum ring about 254mm in diameter is attached to a brass hub by silk cord which is threaded in and out through holes in the ring.   This tight silk cord is act like bicycle wheels.   There is no other connection or support between the ring and the hub.   Silk cord is used because it doesn’t shrink or stretch due to moisture or change in atmospheric temperature.     Card support: -     The bottom of the hub has small cap fi tt ed with a sapphire bearing surface.   This rests on a pivot tipped with iridium which is hard nonmagnetic metal....
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USE OF DUNNAGES

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  1. Dunnages are the wooden blocks or gunny cloths or paper material which are used in cargo holds to protect cargo and their packaging from
  • Moisture.
  • Contamination.
  • Mechanical damage.
  • Lack of ventillation.
  1. Dunnages are of four types.they are
  • Floor dunnage.
  • Lateral dunnage.
  • Inter layer dunnage.
  • Top dunnage.
  1. On general cargo ships, the most important of these is floor dunnage .It protects moisture sensitive cargo such as bagged cargoes (tea and coffee..)or bales( tobacco..)from sweat forms on ship’s sides and runs off over the decks.
  2. Protection of underlying cargo from contamination by a top cargo.
  3. Segregation of individual hatches of cargo.
  4. The floor dunnage lift the cargo off the deck, so that water is able to flow off without coming into contact with the cargo.
  5. To protect sensitive cargoes from contamination.
  6. Most of the general cargo ships have sparceilings.These are wooden planks connected securely to the ship, which prevent direct contact between the cargo and the ship’s side and allow the sweat to flow downward over the steel ship side.
  7. In the absence of spar ceilings, the dunnage or criss cross dunnage must be used. The criss cross consists of nailed criss-cross wise wooden dunnage being nailed vertical uprights.
  8. The ventillation of cargoes is also very important, Dunnages will help to pass the cool air through cargo in appropriate weather condition.
  9. Make sure the wooden Dunnages are dry.


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The magnetic compass is fitted on the upper bridge exactly center line of the ship   It is referred to as standard compass     1. D ry C ard    2. W et C ard   A compass point north because all magnets have two poles north pole, south pole.   The north pole of the one magnet attracted towards the south pole of another magnet     DRY CARD COMPASS   A light aluminum ring about 254mm in diameter is attached to a brass hub by silk cord which is threaded in and out through holes in the ring.   This tight silk cord is act like bicycle wheels.   There is no other connection or support between the ring and the hub.   Silk cord is used because it doesn’t shrink or stretch due to moisture or change in atmospheric temperature.     Card support: -     The bottom of the hub has small cap fi tt ed with a sapphire bearing surface.   This rests on a pivot tipped with iridium which is hard nonmagnetic metal....
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