Ingangsdatum: 01-01-2012
Chapter 12, paragraph 2.2.1.3 – Emergency fire pumps in cargo
ships
1 It should be documented that chapter 12, paragraph
2.2.1.3, of the Code is satisfied and the suction inlet is fully
submerged under all conditions given in this unified
interpretation.
1.1 Operational seagoing condition for which
roll, pitch and heave should be taken into account.
The
lightest seagoing condition should be considered, which is
defined as the ballast condition which gives shallowest draught
at the position of the sea chest and emergency fire pump as
given in the approved stability booklet (or preliminary
stability calculation for new building). The following table
should be applied for the calculation of roll, pitch and heave.
The heave combined pitch and heave combined roll are taken into
account separately.
1.1.1 Heave combined
pitch1 in head sea
| L, m | 75 and
below
| 100 | 125 | 150 | 175 | 200 | 225 | 250 | 300 | 350 and
above
|
 , deg | 4.5 | 4 | 3.2 | 2.7 | 2.3 | 2.1 | 1.8 | 1.7 | 1.6 | 1.5 |
| H,
m | 0.73 | 0.8 | 0.87 | 0.93 | 0.98 | 1.03 | 1.07 | 1.11 | 1.19 | 1.25 |
Note: Values at the
intermediate length of ships are to be obtained by linear
interpolation.
where:
| L: | | length of the ship, in metres, as defined in
the International Convention on
Load Lines in force, or length between
perpendiculars at the ballast draught,
whichever is greater |
| j: | | pitch angle2 as
defined in figure 1 |
| H: | | heave amplitude as defined
in figure 1. |
1.1.2 Heave combined roll in beam sea
Heave combined roll angle2 should
be taken as:
- ships with bilge keels: 11o; and
- ships without bilge keels:
13o.
Figure 1 – Waterline for which heave combined pitch
is taken into account
1.2 The emergency fire pump suction
should be submerged at the waterlines corresponding to the two
following conditions:
a static waterline drawn through the level of 2/3
immersion of the propeller at even keel (for pod or
thruster driven ship, special consideration should be
given); and
the ship in the arrival ballast condition, as per the
approved trim and stability booklet, without cargo and
with 10% stores and fuel remaining.
For either condition, roll, pitch and heave need not be
applied.
1.3 A ship operating solely in sheltered water
issued with SOLAS Certificates should be subject to compliance
with the still water submergence requirements set out in
paragraph 1.2.1 above.
2 In all cases the net positive suction
head (NPSH) available for the pump should be greater than the NPSH
required.
3 Upon completion of the emergency fire
pump installation, a performance test confirming the pump's capacity
required in the FSS Code, chapter 12, paragraph 2.2.1.1, should be
carried out and, if the emergency fire pump is the main supply of
water for any fixed fire-extinguishing system provided to protect
the space where the main fire pumps are located, the pump should
have the capacity for this system. As far as practicable, the test
should be carried out at the draught corresponding to the lightest
seagoing condition.
1 The heave combined pitch is taken into
account as in figure 1.
2
Angle is to be measured from still waterline and downwards.