3.1 Lack of weathertightness may be attributed
to:
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.1 normal use of the hatch cover system, such
as deformation of the hatch coaming or cover due to impact, wear of
the friction pads where fitted, or wear and tear of the cleating arrangement
which may be corrected by a rebuild to restore the original specification;
or
-
.2 lack of maintenance such as corrosion of plating
and stiffeners due to breakdown of coatings, lack of lubrication of
moving parts; cleats, joint gaskets and rubber pads in need of replacement,
or replaced with incorrect specification parts.
3.2 Insecure hatch covers may be particularly
attributed to damage or wear of securing devices, and incorrect adjustment,
hence incorrect pre-tension and load sharing, of cleating systems.
3.3 Shipowners and operators should institute
a programme of maintenance. This maintenance should be directed to:
-
.1 protecting exposed surfaces of plating and
stiffeners of hatch covers and coamings in order to preserve overall
structural strength;
-
.2 preserving the surface of trackways of rolling
covers, and of compression bars and other steel work bearing on seals
or friction pads, noting that surface smoothness and correct profile
are important for reducing wear rates on these components;
-
.3 maintaining hydraulic or mechanically powered
opening, closing securing or cleating systems in accordance with manufacturers
recommendations;
-
.4 maintaining manual cleats in adjustment, with
replacement on significant wastage, wear or loss of adjustment capability;
-
.5 replacing seals and other wear components in
accordance with manufacturers recommendations, noting the need to
carry aboard or obtain such spares of correct specification, and that
seals are designed for a particular degree of compression, hardness,
chemical and wear resistance; and
-
.6 keeping peripheral and cross joint drains,
where fitted, in working order, noting that any drains fitted to the
inboard side of seal lines will have non-return valves for prevention
of water ingress to holds in the event of boarding seas.
3.4 It is recommended that renewal of components
such as seals, rubber washers, peripheral and cross joint cleats are
made at least as a panel set, to facilitate equalisation of securing
loads.
3.5 Shipowners and operators are recommended to
maintain a record of maintenance, and component replacement, to facilitate
statutory surveys by the Administration. All major repairs should
be undertaken only after consultation with the hatch cover manufacturer
and with the approval of the Administration. Hatch cover maintenance
plans should form part of a ship's safety management system as referred
to in the ISM
Code.
3.6 Where a range of cargoes carried requires
different gasket materials, a selection of gasket materials of the
correct specification should be carried aboard, in addition to other
spares.
3.7 At each operation of a hatch cover, the cover,
and in particular bearing surfaces and drainage channels, should be
free of debris and as clean as practicable.
3.8 Attention is drawn to the dangers of proceeding
to sea without fully secured hatch covers. Securing of all covers
should always be completed before the commencement of a sea passage.
During voyages, especially on loaded passages, cover securing devices
and tightness of cleating and securing arrangements should be checked,
especially in anticipation of and following periods of severe weather.
3.9 Containers and other cargoes should not be
stowed on hatch covers unless the covers are designed and approved
for such carriage. Lashings should not be secured to the covers or
coamings unless these are designed to withstand the lashing forces.
It is therefore particularly important to consult the cargo securing
manual when loading on deck.