5.25 ROUTINE INSPECTIONS WHILE DISCHARGING
The cargo discharge plan prepared by the chief officer indicates only
the principal activities (pump, COW and ballast), scheduled for the
discharge port. Each watch officer should build on that plan, at the
beginning of his watch, to develop a schedule of activities for his
personnel for the next four hours. This plan may be in his head, or
better yet in his deck notebook, but making the plan is an essential
effort to ensuring a smooth watch. In making the plan, each cargo watch
officer must consider the cargo discharge plan, the current status of
operations, the weather forecast, the times of tides, arrival of stores,
completion of repairs, scheduled inspections and any other known events.
One principal objective of the plan is to avoid a convergence of events
or activities at one time. The activities of the watch team should be
scheduled to produce a steady activity across the entire period of the
watch.
5.25.1 Tending mooring lines and gangway
Case studies
In July, a 90,000 DWT crude oil tanker was discharging crude oil in Venice.
Storm winds started to blow at 22.25 hours with heavy rain. An emergency
stop was executed and the crew tried in vain to keep the ship alongside
the berth. At 22.30 hours one discharging arm broke and the other was
badly damaged. The oil content of the discharging arm was lost to the
sea. USD 12,000 in expenses were incurred for clean up. Repair requirements
for the arms were extensive and costly, with the final bill totalling
USD 357,000.
In October, a 90,000 DWT tanker was discharging crude oil in Constanza.
At the end of the discharge a strong northerly breeze arose, blowing in
gusts up to 50 knots. The vessel stopped her pumps as two mooring lines
parted forward and one aft. The ship slipped off the berth, fracturing
the discharge arms. Based on damage costs from a previous incident, the
terminal authorities and cargo receivers demanded guarantees for repair
of the arms, dismantling and remounting after repair, loss of earnings
while arms were repaired, oil pollution fines and damages, loss of revenue,
cargo shortage, demurrage and third party liabilities. Guarantee demands
totalled USD 9 million. Final costs were estimated to be USD 3 million.
Case evaluation
A tanker in an offloading berth, near the end of its discharge , is even
more exposed to severe weather than it would be at sea. It has no room
to manoeuvre, or to change its heading and may not be able to add ballast.
Because of this exposure, the master and chief officer must keep as well
informed regarding the weather forecast in port as they are at sea. This
information must be passed on to the cargo watch officers. If severe weather
threatens, the chief officer or cargo watch officer must take early and
effective measures to ensure that the vessel will remain moored securely
alongside the berth. If the weather forecast is so severe that remaining
safely in berth cannot be assured, the cargo discharge should be suspended,
loading arms/hoses disconnected and preparations made to take the ship
off the berth. Where a berth is exposed to weather and sea from its offshore
side, the master must carefully observe the weather forecast and be prepared
to leave the berth if severe weather is forecast from the exposed direction.
If the ship is allowed to remain in such a situation and severe weather
develops quickly, tugs may be unable to work alongside and the vessel
will be trapped against the berth at the mercy of the storm. Tankers and
berths have been severely damaged in this way.
In normal weather conditions, the schedule of tending mooring lines will
be determined by the tide and the offloading schedule. Lines should be
tended immediately before any cargo operation which will require most
or all of the attention of the watch team.
Lines must be tended more frequently when the tide is flooding. Anchorage,
Alaska is an example of a port where the lines must be tended almost continuously
due to the high tidal range. Mooring lines may need to be tended infrequently,
or not at all in some berths, while the tide is ebbing.
After adjustment, winches should always be left with only the brake engaged.
Power should never be left on a winch to 'automatically' tension it, nor
should constant tension winches be left in the automatic position while
moored and loading.
Manning of the cargo watch should be arranged so that there are sufficient
personnel available at all times to properly attend both the mooring lines
and the cargo operation.
Towing off wires should be maintained as indicated in section 5.9.1.
5.25.2 Hoses and loading arms
(See section 3.20.2)
Cargo arms should be checked carefully while stripping cargo ashore
at the end of the discharge. Occasionally the speed pf a reciprocating
pump will set up a harmonic oscillation, or swaying, of the cargo arm.
this swaying action can cause structural stress and may cause the arm
to fail. If loading arm swaying is noted, stop the stripping pump and
then resume stripping at a slower (or faster), stroke rate, meanwhile
watching the cargo arm carefully until the discharge is complete.
5.25.3 Gangway watch
(See section 3.20.3)
5.25.4 Discharge line joints and connections
Cargo discharge pipe joints must be frequently checked for leakage.
Main deck lines will have been under considerable (sagging) stress during
the loaded passage and weaknesses may have developed. Gaskets of flanged
or dresser connections can fail under pressure with two effects:
• Cargo is sprayed into the surrounding area, creating an explosive
vapour hazard and
• Large amounts of cargo are spilled onto the deck, creating a safety
and pollution hazard.
All sections of the discharge line and the manifold connection must
be frequently inspected for leaks.
5.25.5 Safety inspections
Regular checks of personnel safe work practices should be conducted.
Personal protective equipment must be worn when appropriate. Rescue
and fire fighting equipment must be checked for readiness.
The deck watch should be questioned about the necessary responses to
emergencies which may arise and instructed if they respond incorrectly.
5.25.6 Garbage and other discharges
All ships garbage must be retained on board in port or disposed of to
a shore garbage container. Covered containers should be used for storage.The
incinerator should not be used in port. Any unusual discharges from
the engine room area should be reported immediately to the engineer
on watch.
5.25.7 Engine room manning
While the vessel is in port, adequate engineering staff including certified
engineering officers, electricians and sufficient ratings, must be continuously
on board. The provisions of STCW 1978, Resolution 4 should be followed.
5.25.8 Theft
Measures against theft of vessel equipment and crew personal effects
should be implemented, including:
• Exclusion from the ship of any person who does not have an authorised
job on board.
Keeping all offshore means of access secured. Regular inspection of
anchor cables and mooring lines
• Keeping the deck well lit, with regular crew patrols.
• All unused spaces should be kept locked.
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