(a) Ships shall be provided with an efficient
bilge pumping plant capable of pumping from and draining any watertight
compartment which is neither a permanent oil compartment nor a permanent
water compartment under all practicable conditions after a casualty
whether the ship is upright or listed. For this purpose wing suctions
will generally be necessary except in narrow compartments at the ends
of the ship, where one suction may be sufficient. In compartments
of unusual form, additional suctions may be required. Arrangements
shall be made whereby water in the compartment may find its way to
the suction pipes. Where in relation to particular compartments the
Administration is satisfied that the provision of drainage may be
undesirable, it may allow such provision to be dispensed with if calculations
made in accordance with the conditions laid down in Regulation 5 and assumed for the
purposes of Regulations 6 and 7 show that the safety of the ship
will not be impaired. Efficient means shall be provided for draining
water from insulated holds.
(b)
-
(i) Ships shall have at least three power pumps
connected to the bilge main, one of which may be attached to the propelling
unit. Where R is more than 0.50, one additional independent
power pump shall be provided.
-
(ii) The requirements are summarized in the following
table:
Required Subdivision Index R
|
Less
than 0.50
|
and
over 0.50
|
Main
engine pump (may be replaced
|
|
|
by
one independent pump)... ... ... ...
|
1
|
1
|
Independent pumps... ... ... ... ...
|
2
|
3
|
-
(iii) Sanitary, ballast and general service pumps
may be accepted as independent power bilge pumps if fitted with the
necessary connections to the bilge pumping system.
(c) Where practicable, the power bilge pumps shall
be placed in separate watertight compartments so arranged or situated
that these compartments will not readily be flooded by the same damage.
If the engines and boilers are in two or more watertight compartments,
the pumps available for bilge service shall be distributed throughout
these compartments as far as is possible.
(d) On ships 330 feet (or 100 metres) or more
in length or having R more than 0.50, the arrangements
shall be such that at least one power pump shall be available for
use in all ordinary circumstances in which a ship may be flooded at
sea. This requirement will be satisfied if:
-
(i) one of the required pumps is an emergency
pump of a reliable submersible type having a source of power situated
above the relevant bulkhead deck; or
-
(ii) the pumps and their sources of power are
so disposed throughout the length of the ship that under any condition
of flooding which the ship is required to withstand, at least one
pump in an undamaged compartment will be available.
(e) With the exception of additional pumps which
may be provided for peak compartments only, each required bilge pump
shall be arranged to draw water from any space required to be drained
by paragraph (a) of this Regulation.
(f) Each power bilge pump shall be capable of
giving a speed of water through the required main bilge pipe of not
less than 400 feet (or 122 metres) per minute. Independent power bilge
pumps situated in machinery spaces shall have direct suctions from
these spaces, except that not more than two such suctions shall be
required in any one space. Where two or more such suctions are provided
there shall be at least one on the port side and one on the starboard
side. The Administration may require independent power bilge pumps
situated in other spaces to have separate direct suctions. Direct
suctions shall be suitably arranged and those in a machinery space
shall be of a diameter not less than that required for the bilge main.
(g)
-
(i) In addition to the direct bilge suction or
suctions required by paragraph (f) of this Regulation there shall
be in the machinery space a direct suction from the main circulating
pump leading to the drainage level of the machinery space and fitted
with a non-return valve. The diameter of this direct suction pipe
shall be at least two-thirds of the diameter of the pump inlet in
the case of steamships, and of the same diameter as the pump inlet
in the case of motorships.
-
(ii) Where in the opinion of the Administration
the main circulating pump is not suitable for this purpose, a direct
emergency bilge suction shall be led from the largest available independent
power driven pump to the drainage level of the machinery space; the
suction shall be of the same diameter as the main inlet of the pump
used. The capacity of the pump so connected shall exceed that of a
required bilge pump by an amount satisfactory to the Administration.
-
(iii) The spindles of the sea inlet and direct
suction valves shall extend well above the engine room platform.
(h)
-
(i) All pipes from the pumps which are required
for draining cargo or machinery spaces shall be entirely distinct
from pipes which may be used for filling or emptying spaces where
water or oil is carried.
-
(ii) All bilge pipes used in or under fuel storage
tanks or in boiler or machinery spaces, including spaces in which
oil-settling tanks or oil fuel pumping units are situated, shall be
of steel or other approved material.
(i) The diameter of the bilge main shall be calculated
according to the following formulae provided that the actual internal
diameter of the bilge main may be of the nearest standard size acceptable
to the Administration or
where
d
|
= |
internal
diameter of the bilge main (in inches or in millimetres respectively) |
Ls
and B
1
|
= |
in feet or metres respectively |
Ds
|
= |
moulded depth of ship to immersion limit line at midlength (in
feet or metres respectively). |
The diameter of the bilge branch pipes shall be determined by
rules to be made by the Administration.
(j) The arrangement of the bilge and ballast pumping
system shall be such as to prevent the possibility of water passing
from the sea and from water ballast spaces into the cargo and machinery
spaces, or from one compartment to another. Special provision shall
be made to prevent any deep tank having bilge and ballast connections
being inadvertently run up from the sea when containing cargo, or
pumped out through a bilge pipe when containing water ballast.
(k) Provision shall be made to prevent the compartment
served by any bilge suction pipe being flooded in the event of the
pipe being severed, or otherwise damaged by collision or grounding
in any other compartment. For this purpose, where the pipe is at any
part situated nearer the side of the ship than 0.2B
1(measured
at right angles to the centreline at the level of the deepest subdivision
loadline), or in a duct keel, a non-return valve shall be fitted to
the pipe in the compartment containing the open end.
(l) All the distribution boxes, cocks and valves
in connection with the bilge pumping arrangements shall be in positions
which are accessible at all times under ordinary circumstances. They
shall be so arranged that, in the event of flooding, one of the bilge
pumps may be operative on any compartment; in addition, damage to
a pump or its pipe connecting to the bilge main outboard of a line
drawn at 0.2B
1, shall not put the bilge system
out of action. If there is only one system of pipes common to all
the pumps, the necessary cocks or valves for controlling the bilge
suctions must be capable of being operated from above the immersion
limit line. Where in addition to the main bilge pumping system an
emergency bilge pumping system is provided, it shall be independent
of the main system and so arranged that a pump is capable of operating
on any compartment under flooding conditions; in that case only the
cocks and valves necessary for the operation of the emergency system
need be capable of being operated from above the immersion limit line.
(m) All cocks and valves mentioned in paragraph
(1) of this Regulation which can be operated from above the immersion
limit line shall have their controls at their place of operation clearly
marked and provided with means to indicate whether they are open or
closed.