Deck Watch Keeping a Check

• The Inert Gas System recorder to be switched onto record and monitor the cargo tanks pressure
• After adjusting the inert gas pressure in tanks, the
IG system to be stopped when the pressure reaches the prescribed value (usually 1000 mmAq)
81. l Marine Insight Cargo Completion Survey The cargo completion survey is done by the terminal surveyor, who after satisfactory inspection, issues the " Dry certificate / ROB certificate. Cargo Operations for Tanker I 82. Inert Gas Generator Panel Surveyor Making Records

The deck watch officer must attend the terminal surveyor or berth master when cargo tank gauging is done to confirm the tank is free from pumpable liquid) cargo. Any remaining Un-pumpable cargo must be documented with suitable remarks on the certificate. The vessel is to prepare a dry certificate or ROB certificate (in case the cargo tank contains pumpable liquid. The deck officer or chief officer should insist for the copy of the surveyor's document for onboard documentation.
Recordkeeping in Tanker Cargo Log Book Following items shall be recorded in Tanker Cargo Log Book on hourly basis :
• Discharged Quantity (Rate) to compare it with that
83. l Marine Insight of the terminal side
• Cargo levels (ullage) in tanks not being used
• The pumping performance record/pumping log
• PumppPressure and RPM
• Manifold pressure / temperature
• Draft & Trim
• Stress and Stability of the vessel
• Tank pressure
• Issue time and date of the dry certificate or ROB certificate Cargo Operations for Tanker I 84.

Stripping is the process of completely draining down the cargo tanks during discharging. A proper understanding of the ships pumping system is essential to achieve maximum cargo outturn and minimum discharge time.
85. l Marine Insight As the tank sounding reaches 2 meters or less, switch on the auto unloading system, set the vacuum pumps to auto, open gas extraction valve, and put the pneumatic discharge valve on auto. Thus, the auto unloading system maintains the level of cargo in the separator by throttling the pneumatic discharge valve and also by using vacuum pumps to remove air trapped in the line. The remaining pumps can be run into their respective groups. The COP recirculates cargo into slop tank at a high discharge pressure of approximately 8 bars. A vacuum is created by the cargo eductor, which is used to educt the group red utilizing the stripping line connected at the bottom of the tank to the main cargo

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