Section
6 Pumps on bilge service and their connections
6.1 Number of pumps
6.1.1 In ships,
other than passenger ships, with engines up to 220 kW, at least one
power bilge pump is to be provided which may be worked from the main
engine. In addition, hand pump suctions are to be fitted. In ships
with engines exceeding 220 kW, at least two power bilge pumps are
to be provided in the machinery space, one of which may be worked
from the main engines and the other is to be independently driven.
6.1.2 For ships,
other than passenger ships having separate machinery spaces, not connected
to a common bilge system and with installed auxiliary engines up to
220 kW, at least one power bilge pump is to be provided which may
be worked from the auxiliary engine. In addition, hand pump suctions
are to be fitted. For installed auxiliary engines exceeding 220 kW,
at least two power bilge pumps are to be provided in the machinery
space, one of which may be worked from the auxiliary engines and the
other is to be independently driven.
6.1.3 In ships
other than passenger ships, a bilge ejector in combination with a
high pressure overboard water pump may be accepted as a substitute
for an independent bilge pump as required by Pt 5, Ch 11, 6.1 Number of pumps 6.1.1.
6.1.4 For small
passenger ships, additional independent power bilge pumps may be required,
depending on the size of the ship and the proposed service.
6.1.5 For passenger
ships with a Rule length exceeding 80 m, at least three power bilge
pumps are to be provided, one of which may be operated from the main
engines.
6.2 General service pumps
6.2.1 The bilge
pumps required by Pt 5, Ch 11, 6.1 Number of pumps, may also
be used for ballast, fire or general service duties of an intermittent
nature, but they are to be immediately available for bilge duty when
required.
6.2.2 Sanitary,
ballast, bilge or general service pumps may be accepted as fire pumps,
provided that for ships other than passenger ships they are not used
for pumping oil and that, if they are subject to occasional duty for
the transfer or pumping of fuel oil suitable change-over arrangements
are fitted to preclude the admission of oil into the fire main.
6.3 Capacity of pumps
6.3.1 The capacity
of each bilge pump is to be not less than required by the following
formula:
|
Q
|
= |
|
where
|
Q
|
= |
capacity,
in m3/h
|
|
d
m
|
= |
Rule internal diameter of main bilge line, in mm, as per Pt 5, Ch 11, 3.2 Cargo holds 3.2.12, Pt 5, Ch 11, 5.1 Main bilge line 5.1.1 or Pt 5, Ch 11, 5.4 Main bilge line – Tankers and dry cargo ships having machinery spaces with their own bilge arrangements
5.4.1 as applicable.
|
6.3.2 For open
hatch dry cargo vessels, the capacity of each bilge pump unit, based
on heavy rainfall, should be not less than required by the following
formula:
|
Q
|
= |
|
where
|
Q
|
= |
rainfall
mm/h, as applicable for the geographical area in which the ship will
operate with a minimum of 25 mm/h but not required to exceed 100 mm/h |
|
C
h
|
= |
length of the hold, in metres |
|
B
h
|
= |
breadth of the hold, in metres |
The greater capacity as calculated by Pt 5, Ch 11, 6.3 Capacity of pumps 6.3.1 or Pt 5, Ch 11, 6.3 Capacity of pumps 6.3.2 will be applicable.
6.3.3 In ships
other than passenger ships and ships not provided with submersible
bilge pumps, where one bilge pump is of slightly less than Rule capacity,
the deficiency may be made good by an excess capacity of the other
pump. In general, this deficiency is to be limited to 30 per cent.
6.4 Self-priming pumps
6.4.1 All power
pumps which are essential for bilge services are to be of the self-priming
type.
6.5 Pump connections
6.5.1 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.
6.5.2 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.
6.6 Submersible bilge pump arrangements
6.6.1 Arrangements
are to be such that at least two automatic non-return devices are
to be fitted between the overboard discharge and the watertight space
being served by the pump.
6.6.2 One of
these devices is to be fitted at or near the shell as high as practicable
but in any case well above the loaded waterline, and the other one
may be situated in the pipe work to the pump.
|
| Copyright 2022 Clasifications Register Group Limited, International Maritime Organization, International Labour Organization or Maritime
and Coastguard Agency. All rights reserved. Clasifications Register Group Limited, its affiliates and subsidiaries and their respective
officers, employees or agents are, individually and collectively, referred to in this clause as 'Clasifications Register'. Clasifications
Register assumes no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance
on the information or advice in this document or howsoever provided, unless that person has signed a contract with the relevant
Clasifications Register entity for the provision of this information or advice and in that case any responsibility or liability is
exclusively on the terms and conditions set out in that contract.
|
 |
|