1.8 Bilge and ballast
? A fire and bilge pump has suctions from
sea,bilge main and engine room bilge,
with discharges to fire main,oily water
separator and overboard,A ballast pump
has suctions from sea,ballast main,engine
room,bilge direct and bilge main with
discharges to overboard,the ballast main,
the oily water separator and possibly,the
main salt water circulating system,
1.8 Bilge and ballast
? A general service pump has suctions from sea,
ballast main,bilge main and engine room bilge
with discharges to the fire main,the ballast main,
the oily water separator and overboard,In this
way,three pumps provide effective alternatives
for all essential services in the event of
breakdown of one or even two,Many ships will
have more generous provision and all passenger
ships will have a submersible fire and bilge pump,
supplied with power from an emergency dynamo.
1.8 Bilge and ballast
? There are many differences in arrangement; some
ships will be fitted for oil or ballast in all double
bottom tanks (except one or two,port and
starboard for fresh water) some in only two or
three,Other vessels will have one (or more)
lower holds fitted as deep tanks and most will
have peak ballast tanks forward and aft,Some
ships will have a tunnel from the engine room to
No.1 hold aft bulkhead,for bilge,ballast and oil
pipes and fittings and others will have a duct keel
to carry the pipes forward,
1.8 Bilge and ballast
? In most other ships the bilge suction pipes will pass
through the wings of the holds and the ballast pipes
through the double bottom,In the two latter cases,the
valve chests will be on the engine room (or boiler room)
forward bulkhead or in a forward cofferdam,In all cases,
the bilge suction valves will be screw-down,non-return,
the oil and ballast valves,screw-lift,Ring and blank
flanges will be fitted in deep tank suctions,so that ballast
cannot be discharged inadvertently by a bilge pump not the
hold be flooded when used for cargo,If liquid cargoes are
carried,both will be blanked,Note that double bottom
tanks should never be pumped up.
1.8 Bilge and ballast
? The minimum number and capacity of
bilge pumps and fire pumps and their
dispersement within the ship is governed
by:
? 1 Classification Society Rules
? 2 National requirements
? 3 The IMCO International Convention for the
Safety of Life at Sea,1974(SOLAS 74).
1.8 Bilge and ballast
? The basic philosophy is similar in all three cases
but SOLAS 74 only defines bilge pump capacity
for passenger ships and the Convention only
applies to vessels trading internationally; more-
over it excludes cargo ships of less than 500
gross tons,The Classification Societies generally
prescribe the bore of the main bilge line and
branch bilge lines and relate the bilge pump
capacity of each pump to that required to
maintain a minimum water speed in the line; the
fire pump capacity is related to the capacity of
the bilge pump thus defined e.g.
1.8 Bilge and ballast
Bilge main dia,d1=1.68 +25 mm
Branch dia,d2=2.16 +25 mm
d2 not to be less than 50 mm and need not exceed 100 m.
d1 must never be less than d2
where
L = length of ship in m;
B = Breadth of ship in m;
D = Moulded depth at bulkhead deck in m;
C = Length of compartment in m.
)( DBL ?
)( DBL ?
)(C ?
)( DBC ?
1.8 Bilge and ballast
? Each pump should have sufficient
capacity to give a water speed of 122
m/min through the Rule size mains of this
bore,Furthermore each bilge pump should
have a capacity of not less than
? d12 m3/h
310
565.0
1.8 Bilge and ballast
? The fire pumps,excluding any emergency
fire pump fitted,must be capable of
delivering a total quantity of water at a
defined head,not less than two-thirds of
the total bilge pumping capacity,The
defined head ranges from 3.2 bar in the
case of passenger ships of 4000 tons gross
or more to 2.4 bar for cargo ships of less
than 1000 tons gross.
1.8 Bilge and ballast
? The following paragraphs are extracted
from the International Convention for the
Safety of Life at Sea 1974 Chapter 11-1
Regulation 18 which relates to passenger
ships:
1.8 Bilge and ballast
? ‘ 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
connexions being inadvertently run up from the
when containing cargo,of pumped out through a
bilge pipe when containing water ballast.’
1.8 Bilge and ballast
? ‘ Provision shall be made to prevent the
compartment served by any bile 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 one-fifth the
breadth of the ship (measured at right angles to
the centre line at the level of the deepest
subdivision load line),or in a duct keel,a non-
return valve shall be fitted to the pipe in the
compartment containing the open end.’
1.8 Bilge and ballast
? ‘ All the distribution boxes,cocks and valves in
connexion 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 out board of a line drawn at one-fifth of the
breadth of the ship 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 bulkhead
deck,
1.8 Bilge and ballast
? 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
condition; in that case only the cocks and valves
necessary for the operation of the emergency
system need be necessary for the operation of the
emergency system need be capable of being
operated from above the bulkhead deck.’
1.8 Bilge and ballast
? ‘ All cocks and valves mentioned in the
above paragraph of this Regulation which
can be operated from above the bulkhead
deck shall have their controls at their place
of operation clearly marked and provided
with means to indicate whether they are
open or closed.’
? A fire and bilge pump has suctions from
sea,bilge main and engine room bilge,
with discharges to fire main,oily water
separator and overboard,A ballast pump
has suctions from sea,ballast main,engine
room,bilge direct and bilge main with
discharges to overboard,the ballast main,
the oily water separator and possibly,the
main salt water circulating system,
1.8 Bilge and ballast
? A general service pump has suctions from sea,
ballast main,bilge main and engine room bilge
with discharges to the fire main,the ballast main,
the oily water separator and overboard,In this
way,three pumps provide effective alternatives
for all essential services in the event of
breakdown of one or even two,Many ships will
have more generous provision and all passenger
ships will have a submersible fire and bilge pump,
supplied with power from an emergency dynamo.
1.8 Bilge and ballast
? There are many differences in arrangement; some
ships will be fitted for oil or ballast in all double
bottom tanks (except one or two,port and
starboard for fresh water) some in only two or
three,Other vessels will have one (or more)
lower holds fitted as deep tanks and most will
have peak ballast tanks forward and aft,Some
ships will have a tunnel from the engine room to
No.1 hold aft bulkhead,for bilge,ballast and oil
pipes and fittings and others will have a duct keel
to carry the pipes forward,
1.8 Bilge and ballast
? In most other ships the bilge suction pipes will pass
through the wings of the holds and the ballast pipes
through the double bottom,In the two latter cases,the
valve chests will be on the engine room (or boiler room)
forward bulkhead or in a forward cofferdam,In all cases,
the bilge suction valves will be screw-down,non-return,
the oil and ballast valves,screw-lift,Ring and blank
flanges will be fitted in deep tank suctions,so that ballast
cannot be discharged inadvertently by a bilge pump not the
hold be flooded when used for cargo,If liquid cargoes are
carried,both will be blanked,Note that double bottom
tanks should never be pumped up.
1.8 Bilge and ballast
? The minimum number and capacity of
bilge pumps and fire pumps and their
dispersement within the ship is governed
by:
? 1 Classification Society Rules
? 2 National requirements
? 3 The IMCO International Convention for the
Safety of Life at Sea,1974(SOLAS 74).
1.8 Bilge and ballast
? The basic philosophy is similar in all three cases
but SOLAS 74 only defines bilge pump capacity
for passenger ships and the Convention only
applies to vessels trading internationally; more-
over it excludes cargo ships of less than 500
gross tons,The Classification Societies generally
prescribe the bore of the main bilge line and
branch bilge lines and relate the bilge pump
capacity of each pump to that required to
maintain a minimum water speed in the line; the
fire pump capacity is related to the capacity of
the bilge pump thus defined e.g.
1.8 Bilge and ballast
Bilge main dia,d1=1.68 +25 mm
Branch dia,d2=2.16 +25 mm
d2 not to be less than 50 mm and need not exceed 100 m.
d1 must never be less than d2
where
L = length of ship in m;
B = Breadth of ship in m;
D = Moulded depth at bulkhead deck in m;
C = Length of compartment in m.
)( DBL ?
)( DBL ?
)(C ?
)( DBC ?
1.8 Bilge and ballast
? Each pump should have sufficient
capacity to give a water speed of 122
m/min through the Rule size mains of this
bore,Furthermore each bilge pump should
have a capacity of not less than
? d12 m3/h
310
565.0
1.8 Bilge and ballast
? The fire pumps,excluding any emergency
fire pump fitted,must be capable of
delivering a total quantity of water at a
defined head,not less than two-thirds of
the total bilge pumping capacity,The
defined head ranges from 3.2 bar in the
case of passenger ships of 4000 tons gross
or more to 2.4 bar for cargo ships of less
than 1000 tons gross.
1.8 Bilge and ballast
? The following paragraphs are extracted
from the International Convention for the
Safety of Life at Sea 1974 Chapter 11-1
Regulation 18 which relates to passenger
ships:
1.8 Bilge and ballast
? ‘ 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
connexions being inadvertently run up from the
when containing cargo,of pumped out through a
bilge pipe when containing water ballast.’
1.8 Bilge and ballast
? ‘ Provision shall be made to prevent the
compartment served by any bile 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 one-fifth the
breadth of the ship (measured at right angles to
the centre line at the level of the deepest
subdivision load line),or in a duct keel,a non-
return valve shall be fitted to the pipe in the
compartment containing the open end.’
1.8 Bilge and ballast
? ‘ All the distribution boxes,cocks and valves in
connexion 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 out board of a line drawn at one-fifth of the
breadth of the ship 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 bulkhead
deck,
1.8 Bilge and ballast
? 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
condition; in that case only the cocks and valves
necessary for the operation of the emergency
system need be necessary for the operation of the
emergency system need be capable of being
operated from above the bulkhead deck.’
1.8 Bilge and ballast
? ‘ All cocks and valves mentioned in the
above paragraph of this Regulation which
can be operated from above the bulkhead
deck shall have their controls at their place
of operation clearly marked and provided
with means to indicate whether they are
open or closed.’
