Section
15 Requirements for yachts and service craft of 24 m or greater
in length, which are not required to comply with the HSC Code
15.1 General
15.1.1 The requirements of Pt 15, Ch 2, 1 General, Pt 15, Ch 2, 2 Construction and installation, Pt 15, Ch 2, 3 Shell valves and fittings (other than those on scuppers and sanitary discharges), Pt 15, Ch 2, 11 Air, overflow and sounding pipes and Pt 15, Ch 2, 12 Additional requirements relating to fixed pressure water spray fire-extinguishing systems of this Chapter are generally applicable. The remaining
Pt 15, Ch 2, 4 Bilge pumping and drainage systems of this Chapter concerning the requirements for bilge
pumping and drainage systems are replaced by the requirements given in Pt 15, Ch 2, 15.2 Drainage of spaces containing low flashpoint fuel to
Pt 15, Ch 2, 15.30 Bilge level detection.
15.2 Drainage of spaces containing low flashpoint fuel
15.2.1 Where
it is intended to carry vehicles or craft with fuel in their tanks
having a flashpoint (closed-cup test) less than 60̊C for their
own propulsion or having re-fuelling facilities for such vehicles
or craft, a separate bilge system is to be provided.
15.2.2 The
bilge system is to be designed to prevent pumping of flammable liquids
through piping and pumps in machinery, accommodation or any other
spaces where a source of ignition may exist.
15.2.3 For special requirements relating to the separate bilge system, see
Pt 15, Ch 2, 12 Additional requirements relating to fixed pressure water spray fire-extinguishing systems, Pt 15, Ch 2, 15.12 Sizes of bilge suction pipes 15.12.5, Pt 15, Ch 2, 15.14 Pumps on bilge service and their connections 15.14.7 and Pt 15, Ch 2, 15.16 Capacity of pumps 15.16.4.
15.3 Drainage of compartments, other than machinery spaces
15.3.1 All
craft are to be provided with efficient pumping plant having the suctions
and means for drainage so arranged that any water within any compartment
of the craft, or any watertight section of any compartment, can be
pumped out through at least one suction when the craft is on an even
keel and is either upright or has a list of not more than 5o.
For yachts a list of not more than 10 o shall be assumed.
For this purpose, wing suctions will generally be necessary, except
in short, narrow compartments where one suction can provide effective
drainage under the above conditions.
15.3.3 For
a normally inaccessible small void compartment such as an echo sounding
compartment, which is accessed from within a normally inaccessible
space such as a forepeak tank, alternative drainage arrangements to
those required by Pt 15, Ch 2, 15.3 Drainage of compartments, other than machinery spaces 15.3.1 may
be considered. For such arrangements, a warning notice is to be located
in a prominent position specifying the precautions to be taken prior
opening the manhole of the small void compartment. Means are to be
provided to indicate flooding of the compartment without opening,
such as fitting indicator plugs to the manhole. Drainage arrangements
are to be submitted to LR for approval.
15.4 Tanks and cofferdams
15.4.1 All
tanks (including double bottom tanks), whether used for water ballast,
fuel oil or liquid cargoes, are to be provided with suction pipes,
led to suitable power pumps, from the after end of each tank.
15.4.3 Similar
drainage arrangements are to be provided for cofferdams, except that
the suctions may be led to the main bilge line.
15.5 Fore and after peaks
15.5.1 Fuel
oil, lubrication oil and other flammable oils are not to be carried
in forepeak tanks.
15.5.2 Where
the peaks are used as tanks, a power pump suction is to be led to
each tank, except in the case of small tanks used for the carriage
of domestic fresh water, where hand pumps may be used.
15.5.3 Where
the peaks are not used as tanks, and main bilge line suctions are
not fitted, drainage of both peaks may be effected by hand pump suctions,
provided that the suction lift is well within the capacity of the
pumps. Drainage of the after peak may be effected by means of a self-closing
cock fitted in a well lighted and readily accessible position.
15.5.4 Pipes
piercing the collision bulkhead are to be fitted with suitable valves
secured to the bulkhead inside the forepeak. The valves are to be
operable from an accessible position above the freeboard deck on service
craft and above the bulkhead deck on yachts. An indicator is to be
provided to show whether the valves are open or closed. These valves
may be fitted on the after side of the collision bulkhead, provided
that they are readily accessible under all service conditions and
the space in which they are located is not a cargo space. In the latter
case, the valves need not be operable from above the freeboard or
bulkhead deck.
15.5.5 On service
craft required to comply with the International Convention for
the Safety of Life at Sea, 1974, as amended (SOLAS 74) and
on yachts, valves on the collision bulkhead are to be of a screw-down
type.
15.5.6 The
collision bulkhead is not to be pierced below the bulkhead deck by
more than one pipe for transferring the contents of the fore peak.
Where the fore peak is divided into two compartments, the collision
bulkhead may be pierced below the bulkhead deck by two pipes (i.e.
one for each compartment) provided there is no practical alternative
to the fitting of a second pipe. Each pipe is to be provided with
a valve as in Pt 15, Ch 2, 15.5 Fore and after peaks 15.5.4 and Pt 15, Ch 2, 15.5 Fore and after peaks 15.5.5.
15.5.7 For
yachts, when it is necessary to lead additional pipes to machinery
equipment located inside the forepeak, details are to be included
in the documentation required by Pt 15, Ch 1, 2.1 Plans and information.
Attention is drawn to the provision of additional penetrations in
the collision bulkhead being restricted by the UK MCA LY3 Code and
an exemption from the National Authority of the country in which the
ship is to be registered will be required.
15.6 Spaces above fore peaks, after peaks and machinery spaces
15.6.1 Provision
is to be made for the drainage of the chain locker and watertight
compartments above the fore peak tank by hand or power pump suctions.
15.6.2 Steering
gear compartments or other small enclosed spaces situated above the
after peak tank are to be provided with suitable means of drainage,
either by hand or power pump bilge suctions.
15.7 Maintenance of integrity of bulkheads
15.7.1 The
intactness of the machinery space bulkheads, and of tunnel plating
required to be of watertight construction, is not to be impaired by
the fitting of scuppers discharging to machinery space or tunnels
from adjacent compartments which are situated below the bulkhead deck.
15.7.2 No drain
valve or cock is to be fitted to the collision bulkhead. Drain valves
or cocks are not to be fitted to other watertight bulkheads if alternative
means of drainage are practicable.
15.8 Bilge drainage of machinery space
15.8.1 The
bilge drainage arrangements in the machinery space are to comply with Pt 15, Ch 2, 15.3 Drainage of compartments, other than machinery spaces except that the arrangements are
to be such that any water which may enter this compartment can be
pumped out through at least two bilge suctions when the craft is on
an even keel, and is either upright or has a list of not more than
5o. For yachts a list of not more than 10 o shall
be assumed. One of these suctions is to be a branch bilge suction,
i.e. a suction connected to the main bilge line, and the other is
to be a direct bilge suction, i.e. a suction led direct to an independent
power pump.
15.9 Separate machinery spaces
15.10 Machinery space with double bottom
15.10.1 Where
the double bottom extends the full length of the machinery space and
forms bilges at the wings, it will be necessary to provide one branch
and one direct bilge suction at each side.
15.10.2 Where
the double bottom plating extends the full length and breadth of the
compartment, one branch bilge suction and one direct bilge suction
are to be led to each of two bilge wells, situated one at each side.
15.10.3 Where
there is no double bottom and the rise of floor is not less than 5o on
service craft and 10 o on yachts, one branch and one direct
bilge suction are to be led to accessible positions as near to the
centreline as practicable.
15.11 Machinery space - Emergency bilge drainage
15.11.1 In
addition to the bilge suctions detailed in Pt 15, Ch 2, 15.8 Bilge drainage of machinery space andPt 15, Ch 2, 15.9 Separate machinery spaces, an emergency
bilge suction is to be provided in each main machinery space. This
suction is to be led to the main cooling water pump from a suitable
low level in the machinery space and is to be fitted with a screw-down
non-return valve having the spindle so extended that the hand wheel
is not less than 460 mm above the bottom platform.
15.11.2 Where
two or more cooling water pumps are provided, each capable of supplying
cooling water for normal power, only one pump need be fitted with
an emergency bilge suction.
15.11.3 Where
main cooling water pumps are not suitable for bilge pumping duties,
the emergency bilge suction is to be led to the largest available
power pump, which is not a bilge pump.
15.11.4 Emergency
bilge suction valve nameplates are to be marked `For emergency use
only'.
15.12 Sizes of bilge suction pipes
15.12.1 The
diameter, d
m, of the main bilge line is to
be not less than that required by the following formula, to the nearest
5 mm, but in no case is the diameter to be less than that required
for any branch bilge suction:
where
|
d
m
|
= |
internal diameter of main bilge line, in mm |
|
B
|
= |
greatest moulded breadth of craft, in metres, for mono-hull
craft |
| = |
greatest moulded breadth of a single hull in metres, for multi-hull
craft |
|
D
|
= |
moulded
depth to bulkhead deck, in metres |
|
L
|
= |
Rule
length of craft in metres, for service craft |
| = |
length as defined in the International Convention
on Load Lines in metres, for yachts. |
15.12.2 The
diameter d
b, of branch bilge suction pipes
to cargo and machinery spaces is to be not less than required by the
following formula, to the nearest 5 mm, but in no case is the diameter
of any suction to be less than 50 mm:
where
|
d
b
|
= |
internal diameter of branch bilge suction, in mm |
|
C
|
= |
length
of compartment, in metres |
B and D are as defined in Pt 15, Ch 2, 15.12 Sizes of bilge suction pipes 15.12.1
15.12.3 The
direct bilge suctions in the machinery space are not to be of a diameter
less than that required for the main bilge line.
15.13 Distribution chest branch pipes
15.13.1 The
area of each branch pipe connecting the bilge main to a distribution
chest is to be not less than the sum of the areas required by the
Rules for the two largest branch bilge suction pipes connected to
that chest, but need not be greater than that required for the main
bilge line.
15.14 Pumps on bilge service and their connections
15.14.1 For service craft, at least two power bilge pumping units are to be
provided in the machinery space. One of these units may be worked from the main engines
and the other is to be independently driven.
15.14.3 Each unit may consist of one or more pumps connected to the main bilge line,
provided that their combined capacity is adequate.
15.14.5 For yachts, at least two power bilge pumps are to be provided, both of which
are to be independently driven. The arrangement of the bilge pumps and their individual
supplies shall be such that, in the event of any one compartment being flooded at least
one of the pumps is available for removing water from the flooded space and adjacent
compartments. At least one pump shall be located in the machinery space.
15.14.8 Special consideration will be given to the number of pumps for small craft
and, in general, if there is a class notation restricting a small craft to harbour or
river service, a hand pump may be accepted in lieu of one of the bilge pumping
units.
15.15 General service pumps
15.16 Capacity of pumps
15.16.2 The capacity Q of each bilge pumping unit or bilge pump is to be not less
than required by the following formula:
where
|
d
m
|
= |
Rule internal diameter of main bilge line, in mm |
|
Q
|
= |
capacity,
in m3/hour
|
15.16.3 In
service craft, where one bilge pumping unit is of slightly less than
Rule capacity, the deficiency may be made good by an excess capacity
of the other unit. In general, the deficiency is to be limited to
30 per cent.
15.17 Self-priming pumps
15.17.1 All
power pumps which are essential for bilge services are to be of the
self-priming type, unless an approved central priming system is provided
for these pumps. Details of this system are to be submitted.
15.17.2 Cooling
water pumps having emergency bilge suctions need not be of the self-priming
type.
15.18 Pump connections
15.18.1 The
connections at the bilge pumps are to be such that one unit may continue
in operation when the other unit is being opened up for overhaul.
15.18.2 Pumps
required for essential services are not to be connected to a common
suction or discharge chest or pipe unless the arrangements are such
that the working of any pumps so connected is unaffected by the other
pumps being in operation at the same time.
15.19 Direct bilge suction
15.19.1 The
direct bilge suctions in the machinery space are to be led to independent
power pumps, and the arrangements are to be such that these direct
suctions can be used independently of the main bilge line suctions.
In yachts, when only one independent pump is available in the machinery
space, both direct bilges suctions required by Pt 15, Ch 2, 15.10 Machinery space with double bottom 15.10.2 may be led to this pump.
15.20 Main bilge line suctions
15.20.1 Suctions
from the main bilge line, i.e. branch bilge suctions, are to be arranged
to draw water from any compartment within the craft, excepting small
spaces such as those mentioned in Pt 15, Ch 2, 15.5 Fore and after peaks and
Pt 15, Ch 2, 15.6 Spaces above fore peaks, after peaks and machinery spaces where manual pump suctions
are accepted, and are not to be of smaller diameter than that required
by the formula in Pt 15, Ch 2, 15.12 Sizes of bilge suction pipes 15.12.2.
15.21 Prevention of communication between compartments
15.21.1 The
arrangement of valves, cocks and their connections is to be such as
to prevent the possibility of one watertight compartment being placed
in communication with another, or of dry cargo spaces, machinery spaces
or other dry compartments being placed in communication with the sea
or with tanks. For this purpose, screw-down non-return valves are
to be provided in the following fittings:
- Bilge valve distribution chests.
- Bilge suction hose connections, whether fitted directly to the
pump or on the main bilge line.
- Direct bilge suctions and bilge pump connections to main bilge
line.
15.22 Isolation of bilge system
15.22.1 Bilge
pipes which are required for draining cargo or machinery spaces are
to be entirely distinct from sea inlet pipes or from pipes which may
be used for filling or emptying spaces where water or oil is carried.
This does not, however, exclude a bilge ejection connection, a connecting
pipe from a pump to its suction valve chest, or a deep tank suction
pipe suitably connected through a change-over device to a bilge, ballast
or oil line.
15.23 Machinery space suctions - Mud boxes
15.23.1 Suctions
for bilge drainage in machinery spaces and tunnels, other than emergency
suctions, are to be led from easily accessible mud boxes fitted with
straight tail pipes to the bilges and having covers secured in such
a manner as to permit their being expeditiously opened or closed.
Strum boxes are not to be fitted to the lower ends of these tail pipes
or to the emergency bilge suctions.
15.24 Other compartment suctions - Strum boxes
15.24.1 The
open ends of bilge suctions in compartments outside machinery spaces
and tunnels are to be enclosed in strum boxes having perforations
of not more than 10 mm diameter, whose combined area is not less than
twice that required for the suction pipe. The boxes are to be so constructed
that they can be cleared without breaking any joint of the suction
pipe.
15.25 Tail pipes
15.25.1 The
distance between the foot of all bilge tail pipes and the bottom of
the bilge well is to be adequate to allow a full flow of water and
to facilitate cleaning.
15.26 Location of fittings
15.26.1 Bilge
valves, cocks and mud boxes are to be fitted at, or above, the machinery
space platforms.
15.26.2 Where
relief valves are fitted to pumps having sea connections, these valves
are to be fitted in readily visible positions above the platform.
The arrangements are to be such that any discharge from the relief
valves will also be readily visible.
15.27 Bilge pipes in way of double bottom tanks
15.27.1 Bilge
suction pipes are not to be led through double bottom tanks if it
is possible to avoid doing so.
15.27.2 Bilge
pipes which have to pass through these tanks are to have a minimum
wall thickness of 6.3mm. The thickness of pipes made from material
other than steel will be specially considered.
15.27.3 Expansion
bends, not glands, are to be fitted to these pipes within the tanks,
and the pipes are to be tested, after installation, to the same pressure
as the tanks through which they pass.
15.28 Bilge non-return valves
15.28.1 Where
non-return valves are fitted to the open ends of bilge suction pipes
in order to decrease the risk of flooding, they are to be of an approved
type which does not offer undue obstruction to the flow of water.
15.29 Arrangement and control of bilge valves in yachts
15.29.1 Distribution
boxes, valves and cocks in connection with the bilge pumping arrangements
are to be so arranged that, in the event of flooding of any one compartment,
one of the bilge pumps may be operative on that space and adjacent
compartments. For this purpose, it may be necessary to arrange for
remote control of the bilge suction valves from above the bulkhead
deck.
15.30 Bilge level detection
15.30.2 On
yachts, high level alarms are to be provided in bilges into which
fuel or other oils of similar or higher fire risk could collect, under
either normal or fault conditions.
15.30.3 High
level alarms are to be provided in bilges of spaces containing low
flashpoint fuel.
15.30.4 In
addition to the requirements of this Section, for yachts, attention
is to be given to any relevant requirements of the UK MCA LY3 Code.
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