3.13 SETTING THE VALVES FOR LOADING
Cargo valves will normally be set for the loading operation while
the loading hoses/arms are being connected. The setting of valves should
be done according to a written plan, with each valve identified by a
unique identity number (or other code) and its open or closed position
noted. An independent check of the valve alignment must be performed
to discover any one-man-errors in the cargo system loading alignment.
When all valves in the cargo system have been set for loading, the manifold
valve at the shore connection should be the only valve closed against
the flow of cargo into the ship.
3.13.1 Valve setting procedure
The basic rule for setting cargo valves is that 'any valve not required
for the loading operation must be closed'. The easiest way to ensure
this is to first close all cargo valves in the ship, then systematically
open only those valves to be used for the first phase of the loading
operation. This is easily done from an automated CCR, but more difficult
on tankers with manual valves. This procedure includes a check of the
offshore manifold valves.
The valve setting orders should be used as a checklist. The completed
checklist should be signed by the officer in charge of setting the valves.
3.13.2 Valve position indicators
The cargo officers and pumpmen must fully understand the functioning
of the ship's valve position indicators and the modes of failure of
the indicators. This is particularly important on automated vessels
with CCR operation. Wherever possible, critical valves should be examined
visually to ensure that they are in the same position as indicated in
the CCR. Any valve which shows an ambiguous signal when actuated in
the CCR should be considered suspect and not used until it can be checked.
It may be necessary to disable the remote function of the valve and
operate it locally by hand until necessary repairs are made. If this
is done, a written note that the valve control has been disconnected
must be placed on the CCR valve control board, on the CCR status board
and in the cargo orders.
3.13.3 Independent check
After the valves have been set, an independent check should be conducted
under the supervision of an officer who did not participate in the initial
valve setting. Once again, the valve setting orders should be used as
a checklist and the completed audit signed by the verifying officer.
3.13.4 Pumproom check
In most cases, the pumproom piping will not be used for cargo loading.
In that case, all block valves to the pumproom should be closed and
all valves in the pumproom systems should be closed. If one pumproom
line is to be used for loading, all other lines should be isolated from
it and all other valves closed.
Sea suction valves must be closed, lashed and sealed (except SBT discharge
valves).
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