Loadline reg

8/10/2019 Loadline reg

1/18

Freeboard

Assignment


2/18

Assignment FreeboardThe FreeboardAssignedis the

distance measured

vertically downwardsat amidships from the

upper edge of the deck

line to the upper edgeof the related load line

when floating in SW.


3/18

Purpose of Freeboard

regulations

Ensure adequate reserve buoyancy

Ensure adequate stability

Avoid excessive stress on the ships

hull due to overloading

Protection of crewaccess, railings

etc..


4/18

Freeboard Deck

Normally it is the uppermostcontinuous deck exposed to weather

and sea

Has permanent means of closing allopenings in the weather part thereof

Below which all openings in the sides

of the ship are fitted with permanent

means of watertight closing


5/18

Deck line A horizontal line marked amidships on

each side of the ship.

The upper edge of which corresponds

with the upper surface of the freeboard

deck.

It may be displaced e.g. due to a roundedshearstrake (tankers, bulkers)


6/18

Method of Assignment

Carried out by a Surveyor

Identifies the basic ship type, A or B

Assigns a Tabulated Freeboard Assesses Type B ships for further

reduction, B-60 or B-100 & other

corrections to obtain Basic Freeboard Applies further corrections to obtain

Assigned Freeboard.


7/18

TYPE A SHIP Characteristics

Vessels designed to only carry liquidcargoes in bulk

Small, watertight openings closed by steel covers

Freeboard deck has a high integrity with a low

permeability of loaded cargo spaces

There is a high degree of sub-division


8/18

If the vessel is over 150m long and has emptycompartments when fully loaded at the Summer

Loadline she should be capable of remaining

afloat after the flooding of such compartments(assumed permeability of 95%) in a prescribed

Condition of Equilibrium.

If over 150m long then the machinery space isconsidered as a floodable compartment (assumed

permeability 85%)

TYPE A SHIP


9/18

STATE OF EQUILIBRIUM

Final waterline MUST BE below any opening

that allows progressive flooding

Final angle of heel not to exceed 15 (17 if

deck edge not immersed).

Final GM at least 0.05m.

Residual Stability

Max. GZ not less than 0.1m. Positive range at least 20

Remaining Area under the curve at least

0.0175 mr.


10/18

ASSUMED DAMAGE

Vertical

from keel to deck


11/18

ASSUMED DAMAGE Transverse20% of the beam or 11.5m

(whichever the least)


12/18

ASSUMED DAMAGE Longitudinallybetween transverse

bulkheads (B-100to include 1 bulkhead otherthan machinery space bulkhead)


13/18

ASSUMED DAMAGE

Verticalfrom keel to deck

Transverse20% of the beam or

11.5m (whichever the least)

Longitudinallybetween transverse

bulkheads (B-100 to include onebulkhead other than machinery space

bulkhead)


14/18

TYPE B SHIP

Any ship other than a Type-A ship

have greater vulnerability and therefore require

a larger freeboard

Type B ships have less sub-divisionMore vulnerable to flooding in heavy weather

Have large deck openings


15/18

TYPE B-60 SHIP

Must be over 100m long

Steel weathertight hatch covers

Must remain afloat in the Condition of Equilibrium

after the flooding of a single compartmentIf the above conditions are met then the Tabulated

Freeboard may be reduced by 60% of the difference

between A & B


16/18

TYPE B-100 SHIP

In addition to Type B-60

Steel watertight hatch covers

E.Rm access from the deck protected by a deck house

Open rails, not bulwarks, for 50% of the ships length

Crew access between Poop & detached bridge must be

by gangway or under deck passage


17/18

TYPE B-100 SHIP

In addition to Type B-60

Must remain afloat in the condition of Equilibrium after

the flooding of a any 2 fore & aft adjacent compartments

compartment( = 95%). If the ship is over 150m long

then the machinery space alone can be regarded as a

floodable compartment ( = 85%).If the above conditions are met then the Tabulated

Freeboard may be reduced by 100% of the difference

between A & B


18/18

ASSUMED DAMAGE

Verticalfrom keel to deck

Transverse20% of the beam or

11.5m (whichever the least)

Longitudinallybetween transverse

bulkheads (B-100 to include onebulkhead other than machinery space

bulkhead)

Loadline reg

Documents

Transcript of Loadline reg