procedure to Supply Inert Gas to the Cargo Tanks during the discharge Operation
3.3 LOadING CarGO
3.3.1 LOadING a SINGLE GradE CarGO
Prior to arrival at the load port a number of checks and tests must be carried out to verify the correct operation of the cargo hydraulic and monitoring systems.
The check lifts on each pressure vacuum valve (PV) must be operated to confirm that the valves are free to operate on their seats before loading. In addition the check lifts fitted to the main vent riser PV valve should be operated, and the check lift on the pressure regulating valve situated at the main vent riser.
After planning the stability, taking into consideration the maximum permissible draught, bunkers, water and extras, the loading of a single grade homogeneous cargo can be relatively straightforward.
Note: All loading operations are carried out via the Damcos computer workstation, all remote hydraulic valves are operated using the Damcos computer control switches, both for the open/close and proportional type.
All manually operated valves only have their location indicated on the screen display.
a) Ensure that all of the tank isolating valves to the inert gas (IG) line are open and that all spectacle pieces are swung to the open position and the tank hatches are securely closed.
b) Check that the IG deck isolating valves, NDV002 and NDV005 are closed.
When preparing the system to load cargo, it is important to ensure that all cargo valves are in the closed position prior to the setting of the cargo lines.
c) Ensure that all overboard valves are in the closed/locked and sealed position and that the spectacle pieces are swung and closed in the closed position. These may be sealed at the load port by shore personnel.
d) Ensure that all unused manifold valves are blanked and shut. All manifolds may be sealed after loading by shore personnel.
e) The main vent mast riser manual valve NDV012, will need constant adjustment during loading. The pressure regulating valve (VOCON) is in operation during loading. Refer to Section 3.2.2 for loading with Vapour Emsission Control (VEC).
f) Open the pump bypass loading valves, the pump room bulkhead master valves and the required tank suction valve.
g) Open the manifold valves to which the loading arms are connected.
h) Commence loading cargo at the agreed slow rate into one tank.
When cargo is confirmed as coming into the selected tank, other tank valves may be opened as required and the loading rate increased to the agreed figure.
Note: It is important to note that in order to prevent any slops passing into adjacent tanks when loading into the slop tanks which already contain slops;
do not load into the slop tanks until the cargo tanks are at a slightly higher ullage than the slop tanks. This vessel would normally carry slops in the starboard slop tank.
i) Create an appropriate stagger for controlled topping-off and reduce the loading rate in ample time. The small slop tanks may fill well ahead of the other cargo tanks.
j) Ensure the ballast operations are completed in advance of the final topping-off.
The trimming tanks are the slack cargo oil tanks (CoTs) resulting from trim, draught or nominated cargo restrictions. These are normally cargo centre tanks.
Using centre tanks No.1 and No.3 for final trim and draught requirements may prove advantageous.
Trimming tanks are filled to pre-planned ullages and then shut. They are brought to their final ullage towards the end of loading, at a reduced loading rate.
It is always advisable to complete loading in a slack tank in order to reduce the risk of a carry-over of cargo to the inert gas main.
Deballasting is to be started in accordance with the loading plan, which is generally after bulk loading is under way. Consideration should be made to ensure adequate stern trim is maintained during the ballast tank stripping. Refer to Section 3.7, Ballasting of this manual.
This load plan is for a single grade cargo and has all bottom cargo tank lines common. All tanks are loaded simultaneously for a maximum loading rate, providing stability and trim criteria can be met during the loading and deballasting operation. If such acceptable criteria cannot be met, consider reducing the number of tanks open at any one time, or loading can follow the illustrated multigrade load.
position description Valve
Close Deck main IG isolating valve NDV002
Close Deck main IG isolating valve NDV005
As required Adjust manually the mast riser valve NDV012 Open No.1 cargo oil pump bypass valve CLV061 Open No.2 cargo oil pump bypass valve CLV062 Open No.3 cargo oil pump bypass valve CLV063 Open No.1 bottom line bulkhead valve CLV052 Open No.2 bottom line bulkhead valve CLV053 Open No.3 bottom line bulkhead valve CLV054
Open Lines No.1, 2 and 3 segregation valves CLV001, CLV002 CLV003, CLV004 CLV005, CLV006 CLV007, CLV008 CLV026, CLV027 CLV028, CLV029 CLV033, CLV034 CLV035, CLV036
Open No.5 centre tank valves CLV024, CLV050
Open No.1, 2, 3 and 4 manifold valves port
or
No.1, 2, 3 and 4 manifold valves starboard
CLV157, CLV156 CLV155, CLV154 or
CLV161, CLV160 CLV159, CLV158
Note: No.4 manifold is always common with No.3 line and manifold.
Section 3.3.1 - Page 2 of 4
Issue: Final Draft - November 2007 IMO No: 9323948
Deck Operating Manual
Maersk Nautica
ODME Control Signal
H Main Deck
15 25
From
Compressed Air CLV130
CLV 128
No.4 Cargo Oil Tank (Starboard) No.4 Cargo Oil Tank (Port)
Illustration 3.3.1a Loading a Single Grade Cargo
CLV
Cargo Grade 1
CLV 037
No.1 Cargo Oil Tank (Port)
No.1 Cargo Oil Tank (Starboard) No.1 Cargo
Oil Tank (Centre) No.2 Cargo
Oil Tank (Centre) No.3 Cargo
Oil Tank (Centre) No.4 Cargo
Oil Tank (Centre) No.5 Cargo
Oil Tank (Centre)
CLV005 CLV006 CLV008 CLV007
CLV
100 700
700
700
200
200
700 700 700
25
150 150
200
750 250 550 250 550 250 550
550
No.2 Cargo Oil Tank (Port)
No.2 Cargo Oil Tank (Starboard)
No.3 Cargo Oil Tank (Port)
No.3 Cargo Oil Tank (Starboard)
No.4 Cargo Oil Tank (Port)
No.4 Cargo Oil Tank (Starboard)
No.5 Cargo Oil Tank (Port)
No.5 Cargo Oil Tank (Starboard) Slop Tank
(Port)
Slop Tank (Starboard) CLV CLV 030
009
CLV080 CLV100
CLV116 Compressed Air
CLV099
To Tank Cleaning Main Double
Bottom
Pump Room Bilge Suction From DrainTank
From
CLV058 CLV055
VUV002
CLV106 CLV092
CLV132
CLV 077
CLV CLV118 076
CLV117
From Inert Gas Main Line
CLV108
Emergency Connection with Ballast System ChestSea
No.1 Cargo Oil Pump 5,500m3/h
No.2 Cargo Oil Pump 5,500m3/h
No.3 Cargo Oil Pump 5,500m3/h
Stripping Pump 125m3/h
CLV069
CLV068
CLV101 CLV102
CLV125
Issue: Final Draft - November 2007 IMO No: 9323948
k) Commence loading at the agreed slow rate until the initial safety and integrity checks are completed and cargo is being received into the first cargo tank, then open all tanks in the loading plan and slowly increase to the agreed full loading rate. As loading is through the pump room frequent checks should be made in the pump room.
position description Valve
Open No.1 centre tank cargo valves CLV012, CLV038 Open No.2 centre tank cargo valves CLV015, CLV041 Open No.3 centre tank cargo valves CLV018, CLV044 Open No.4 centre tank cargo valves CLV021, CLV047 Open No.1 wing tank cargo valves CLV011, CLV037 CLV013, CLV039 Open No.2 wing tank cargo valves CLV014, CLV040 CLV016, CLV042 Open No.3 wing tank cargo valves CLV017, CLV043 CLV019, CLV045 Open No.4 wing tank cargo valves CLV020, CLV046 CLV022, CLV048 Open No.5 wing tank cargo valves CLV023, CLV049 CLV025, CLV051 Open Slop tank cargo valves
(dependent upon ullage)
CLV030, CLV031 CLV032
l) Shut the required trimming tanks at a suitable ullage, adjusting the loading rate as required. It is important to ensure that both valves on the tanks are closed when the correct ullage is achieved.
m) Create an appropriate stagger for controlled topping-off and reduce the loading rate in sufficient time, remembering that loading may be undertaken through the smaller stripping suctions for greater control of the final flow into each tank.
n) Top-off the wing tanks first, then top-off the centre tanks and finally finish on the trimming tanks. It is important to ensure that both valves on the tanks are closed when the correct ullage is achieved.
o) On completion of the cargo loading leave the final finishing tank open to drain down the lines. Manifold drain down is accomplished via drains into No.4 starboard cargo tank for starboard manifold loading, and into No.4 port cargo tank for port side manifold loading. Be advised by the port procedure regarding hose draining.
p) Agree the ship/shore figures and disconnect the loading arms, ensuring that the manifolds are shut and the drain valves have cleared the connections.
q) Ensure the tank pressure is kept at an acceptable level for the tank survey and for safety.
r) Climatic conditions may dictate leaving all main cargo lines open into the last loaded tank only, to allow for thermal expansion, until it can be established that this is no longer required.
s) Record all operations in the Port Deck Log Book.
t) Record details in the official Oil Record Book as required for the cargo loaded.
CauTION
The main cargo valves are not proportional valves, and so can only be set either fully open or fully closed and usually take 1 minute to move to the requested position. as such, great care must be taken when topping-off so as not to over-pressurise the pipelines during final topping-topping-off.
Final adjustments can be made to the tank levels via loading through the stripping suction valves, only when the load rate is reduced.
The above illustrated load procedure shows the optimum manifold connections in use with all pipelines common in the bottom lines. Sometimes the vessel may not be presented with all four manifold connections, and in such cases the pipeline configuration can be adjusted to ensure all lines and tanks are common.
The final line set-up will depend upon a various range of circumstances and criteria, but the options available to the vessel are to common the deck lines at the deck line crossover valves, CLV151, CLV152 and CLV153, adjacent to the manifolds.
For loading rates, refer to the VECS Manual and Load Rate XL Sheet.
Section 3.3.1 - Page 4 of 4
Issue: Final Draft - November 2007 IMO No: 9323948
Deck Operating Manual
Maersk Nautica
H Main Deck
15 25
From
Compressed Air CLV130
CLV 128
No.4 Cargo Oil Tank (Starboard) No.4 Cargo Oil Tank (Port)
Illustration 3.3.2a Loading a Two Grade Cargo
CLV
Cargo Grade 1 Cargo Grade 2
CLV 037
No.1 Cargo Oil Tank (Port)
No.1 Cargo Oil Tank (Starboard) No.1 Cargo
Oil Tank (Centre) No.2 Cargo
Oil Tank (Centre) No.3 Cargo
Oil Tank (Centre) No.4 Cargo
Oil Tank (Centre) No.5 Cargo
Oil Tank (Centre)
CLV005 CLV006 CLV008 CLV007
CLV
100 700
700
700
200
200
700 700 700
25
150 150
200
750 250 550 250 550 250 550
550
No.2 Cargo Oil Tank (Port)
No.2 Cargo Oil Tank (Starboard)
No.3 Cargo Oil Tank (Port)
No.3 Cargo Oil Tank (Starboard)
No.4 Cargo Oil Tank (Port)
No.4 Cargo Oil Tank (Starboard)
No.5 Cargo Oil Tank (Port)
No.5 Cargo Oil Tank (Starboard) Slop Tank
(Port)
Slop Tank (Starboard) CLV CLV 030
009
CLV080 CLV100
CLV116 Compressed Air
CLV099
To Tank Cleaning Main Double
Bottom
Pump Room Bilge Suction From DrainTank
From
CLV058 CLV055
VUV002
CLV106 CLV092
CLV132
CLV 077
CLV CLV118 076
CLV117
From Inert Gas Main Line
CLV108
Emergency Connection with Ballast System ChestSea
No.1 Cargo Oil Pump 5,500m3/h
No.2 Cargo Oil Pump 5,500m3/h
No.3 Cargo Oil Pump 5,500m3/h
Stripping Pump 125m3/h
CLV069
CLV068
CLV101 CLV102
CLV125
Issue: Final Draft - November 2007 IMO No: 9323948