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DG Shipping to issue marksheet along with COC

DG shipping has taken new initiative to issue the mark sheet. For the first time marksheets are being issued to all candidates of foreign going grades on sucessful completion of written and oral examination along with the Certificate of Competency (CoC) for nautical wing. Marksheet for 2nd Mate(FG), Master (FG) and 1st Mate(FG) started issuing from 1st, 19th and 30th September, 2016, respectively. Below is the notice diplayed in dgshipping official website. No message has not yet come for the engineering wing.

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Ballast water management (BWM) convention to enter into force in sep 2017

The International Convention for the Control and Management of Ships' Ballast Water and Sediments (BWM Convention) will enter into force on 8 September 2017. The convention stipulates that it will enter into force 12 months after ratification by a minimum of 30 States, representing 35% of world merchant shipping tonnage. Finland ratified this convention on 8th september 2016 to make the total gross tonnage to 35.1 percent and contracting parties to 52. So, after 12 months from this date, this convention will come into force on 8th september 2017.

This convention deals with halting the spread of invasive aquatic species, which can cause havoc for local ecosystems, affect biodiversity and lead to substantial economic loss. Under the Convention's terms, ships will be required to manage their ballast water to remove, render harmless, or avoid the uptake or discharge of aquatic organisms and pathogens within bal'iast water and sediments

The BWM Convention was adopted in 2004 by the lnternational Maritime Organization (lMO), the United Nations specialized agency with responsibility for developing global standards for ship safety and security and for the protection of the marine environment and the atmosphere from any harmful impacts of shipping.

From 8 September 2017, all ships of 400gt and above will be required to have onboard
- An approved Ballast Water Management plan
- A Ballast Water Record Book.
- All ships fitted with Ballast water treatment systems must have a type approval certificate in compliance with the IMO Guidelines for the approval of ballast water management systems
- An International Ballast Water Management Certificate or statement of compliance.

Master checker - seafarers personal database in dg shipping e-governance profile

 All the seafarers have been provided with the facility to view his or her details in the master Checker in his profile. In the Master Checker, the candidate can view all the data such as CDC details, Training details, sea service details, COC details, details of other certificates like Watch keeping, Dangerous Cargo endorsement, GMDSS etc.

It is mentioned that this data is uploaded in the system by the issuing authorities. Therefore, if there is any corrections to be made in the data or if some details are found missing, then the candidates please approach the respective authorities/agencies as under-
-INDOS database- INDOS cell
-CDC details- Respective Shipping Master
-Training details- Respective Maritime Training Institute
-COC details- Nautical or Engineering wing of DGS
-WKC/ Dangerous Cargo/GMDSS- Respective MMDs
-Sea service details- Shipping Company if Articles of Agreement is to be uploaded or RPSL if the -Form -IIIA is to be uploaded. (It is mentioned here that the RPSL cannot uploaded the data which is more than three months old).

All seafarers has to make sure that RPSL agencies, Maritime Training institutes and the Ship owners have uploaded the data regularly in time, so that the seafarer is not inconvenienced at the time of the assessment for examination or endorsements.

Explain shipping term Sheer and its purpose

This article explains the terms sheer, flare and camber in ship construction and its purpose

Sheer is the rise of the deck in a fore and aft direction. The amount of the sheer is measured vertically from a level line through the deck at the midship to the deck at the two perpendiculars.

a) To increase the reserve buoyancy at the ends of the vessel.
b) To counter the immersion of the ends that may occur during pitching and is important particularly for smaller vessels
c) To increase the "Seaworthiness of the ship, that is amount of water coming in on deck would be reduced
d) since fore end is more susceptible to immersion than the aft end, "standard sheer is a parabolic curve with sheer twice that of sheer aft. Modern ships have straight line sheer, often in the fore body only, in some cases only over the forward one third ship's length. Sometimes, very large ships, the minimum bow height is achieved without the need for sheer, conversely, very small vessels may hve very large sheer forward and aft

Flare and its purpose

Camber and its purpose

Explain Camber in ship construction and its advantage?

This article explains the definition and purposes of camber, sheer and flare.

Camber is the rise of the deck from the ships side to the centerline,

a) to facilitate drainage of water,
b) Increase the resistance to deflection under load;
c) Standard camber is parabolic and approximately 1/50th of the breadth of the ship. Modern ships have "dog-log' camber where they are level across the deck between the hatches then dropping in a straight line to the deck at side.
d) the upper deck were to be constructed flat, the humps & hollows that occur due to welding distortion would delay complete drainage.

Flare and its purpose

Sheer and its purpose

Define Flare in ship construction and its purpose

This article explains that Definition of flare, camber, sheer and thier purposes.

Flare It is the outward curvature of the shell at the forward end of the ship.

a) It increases the reserve of buoyancy at the forward end to give better seaworthiness when pitching.
b) water is dispersed away from the ship when lightly pitching (driver deck)
c)  creates it wider forecastle deck, giving more spaces for the fitting off machinery such as the windlass
d)  allows it cleared up life of the anchor from the water, thuz reducing hul damage by abrasion

Sheer and its purpose

Camber and its purpose

What is the need for preferential tripping in marine electrical distribution system

 In marine electrical distribution system, a major consideration is that the supply of power to the switch board must be maintained, if possible. Otherwise a black out situation due to tripping of alternator breaker can endanger the safety of the vessel itself especially in restricted waters and maneouvring. The breaker therefore is to be arranged to trip instantly only in the event of fault such as short circuit. When over current is not so high, time delays with inverse definite Minimum Time relays are provided by way of preference trips which are designed to shed non-essential switchboard load. Preference trips are operated by relay set at about 110 percent of the normal full load, but with different time delays to open the breakers feeding non essential feeders such as galley load, ventilation fan, AC, etc, thereby reducing the load on alternator and saving the main breaker to trip

conditions for synchronizing of two electrical alternators (generator on parallel) on board ship

Three conditions must be fulfilled before an incoming alternator can be connected to the live busbar system.
 i) The voltage of the incoming alternator must be same or within acceptable limits of the busbar voltage. This to be checked from the Voltmeter.
ii)  The frequency of the incoming alternator must be same or within acceptable limits olthe busbar frequency.However in practice, the incoming alternator frequency is to be kept slightly higher, i.e. synchroscope to move clockwise at a slow speed, because when it will come on load there will be drop in speed and then it will match with the busbar frequency.
iii) Phase angle of the incoming alternator must be matched with that of the busbar, indicated by the synchroscope pointer at 12'0 clock position. Which means phase angle difference between corresponding phases of incoming alternator and that of bulbar must be zero or within acceptable limits.

Explain Skin effect and proximity effect in current carrying conductor. How it effect the system

Skin Effect :
When an alternating current flows through a solid conductor, the distribution of current across the cross section of the conductor found to be non-uniform and the current tends to flow around the surface of the conductor. This effect is called skin effect. It is more pronounced at high frequencies and with conductors of large cross sections. Since the inner core of the conductor is linked with larger amount of magnetic flux than the outer surface, it is having larger impedance to alternating currents than the Outer surface and hence current and current density tend to he greater in the outer surface.This reduces the effective area of section of the conductor. rherefore a hollow conductor bus is best suited and economical to transmit high current.

Proximity effect
When two conductors are placed near to each other carrying high currents. then half portion of the conductor links with more magnetic flux being nearer and the other half gets less flux linkage being further away. This causes non-uniformity of current flow across the cross-section of the conductors due to the increase in impedance in part of the conductors.
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