Tanker Operations Quiz

Significantly reduces pollution risk and allows for easier tank cleaning.

Higher construction and maintenance costs, potentially faster corrosion and cracking than single-hull tankers.

Introducing inert gas into a tank to lower hydrocarbon levels below 2% to prevent flammability.

A process to remove flammable gases and vapors from a space.

Allows flow in one direction only (typically on the discharge side of a cargo pump).

The space above liquid cargo in a tank, measured from the top of the liquid to a higher reference point.

The lowest temperature at which a liquid gives off enough vapor to ignite.

A measure of a liquid's resistance to flow.

Water supply hoses contain internal wires that act as conductors for electrical power, providing the necessary electricity for the tanker.

A designated person, known as the PIC (Person in Charge), must supervise all functions aboard a tanker and its associated barges.

Topping off, the final stage of loading cargo oil, is the time with the highest risk of oil pollution due to potential spills or overflows.

Power Packs provide high-pressure hydraulic oil to operate the hydraulic pumps used for various functions on the tanker.

Mooring lines on working drums should have about 3-4 wraps to ensure proper securement and minimize slippage.

If a leak develops at the connection between the shore hoses and the manifold, immediately stop pumping and replace the leaking gasket before resuming.

Cavitation occurs in a centrifugal pump when the pressure in the suction line falls below the vapor pressure of the cargo, leading to the formation of vapor bubbles. This can be caused by loss of prime or low pump speed.

Eductors use the venturi effect to create low pressure in a suction line by expelling drive fluid (usually slops) through a narrow opening. This low pressure is then used to draw up fluids for stripping operations.

A crossover allows transfer of cargo between different tank sections or segregation zones on an oil tanker. It is used to move cargo between systems or compartments.

P/V (Pressure/Vacuum) Valves protect tanks from over-pressurization or under-pressurization. They automatically open or close to maintain a safe pressure range within the tank.

A metritape gauging system measures the level of cargo in tanks. It uses a stainless steel core with an exposed strip, wrapped in wire that makes contact when squeezed, providing a precise reading.

Inert Gas systems must deliver gas with less than 8% oxygen (O2) to create an inert atmosphere and prevent explosions.

When discharging oil, the primary focus is on getting the bow (front) of the ship up to maintain stability and prevent the ship from listing.

Excessive air in the suction line during stripping can lead to a loss of suction, making it difficult to pump out the remaining cargo.

The source tank for cleaning machines in a crude oil washing system must have at least one meter of decanted oil removed from it.

Topped off cargo tanks in cold weather risk overflowing when the temperature rises due to thermal expansion of the cargo.

A tanker with two hulls, an outer hull and an inner hull, providing extra protection against spills and making cleaning easier.

Purging introduces inert gas to an already inert tank to reduce hydrocarbons below 2%, preventing flammability. Gas-freeing removes flammable gases and vapors from a space, making it safe to enter.

A unit of volume equivalent to 42 gallons at 60°F.

Piping that directs cargo from the main line to individual tanks.

A valve allowing flow in one direction only, typically found on the discharge side of a cargo pump.

A measure of a liquid's resistance to flow.

The smallest percentage of vapor in the air that will allow for an ignitable mixture.

A single fitting that either blanks off a pipeline or allows full flow.

A system on an oil tanker that allows cargo transfer between different tank sections or segregation zones.

A valve that safeguards oil tanks from over-pressurization and under-pressurization, ensuring safe pressure levels within the tank.

A system used to measure cargo levels in tanks. A stainless steel core with an exposed strip, wrapped in wire making contact when squeezed, gives accurate readings.

System supplying low-oxygen gas (less than 8%) into tanks to prevent explosions.

Priority during oil discharge, ensuring the ship's front end is raised for stability.

Can lead to a loss of suction while stripping, making it difficult to pump out remaining cargo.

Minimum requirement for cleaning machines in crude oil washing systems: one meter of decanted oil in the source tank.

Cargo tanks should not be fully filled in cold weather due to potential overflow when temperatures increase.

Topping off is the final stage of cargo loading, where the tank is filled to its capacity.

Cargo pumps are generally positioned aft (toward the rear) of the vessel, near the centerline of the tank.

Cavitation happens when the pressure in the suction line drops below the vapor pressure of the cargo, creating vapor bubbles.

The Inert Gas System creates an inert atmosphere in tanks to prevent explosions by reducing oxygen levels.

The VGP (Voluntary Guidelines for Tankers) mandates daily visual inspections of the Inert Gas System.

A designated PIC (Person in Charge) is responsible for supervising all functions aboard the tanker.