CARGO OPS ; Cargo Systems, COW, Definitions, Tanker Work Flashcards
What is a characteristic of all centrifugal cargo pumps?
Decreasing the speed of rotation will decrease the discharge pressure
The system of valves and cargo lines in the bottom piping network of a tank barge that connects one section of cargo tanks to another section is called a __________.
crossover
What is NOT an advantage of centrifugal pumps over reciprocating pumps?
They require priming for stripping
The purpose of a bilge well is to __________.
collect water to be pumped out
What is TRUE of pressure/vacuum valves?
They are designed to provide for the flow of small volumes of tank atmospheres caused by thermal variations in a cargo tank
They should operate in advance of the pressure/vacuum breakers.
They should be kept in good working order by regular inspection and cleaning
When stripping a tank, excessive air in the suction line may cause __________.
loss of suction
Which statement is TRUE of centrifugal pumps aboard tankers?
They are gravity-fed
Which statement about a centrifugal cargo pump is TRUE?
It must have a positive suction
Which statement is TRUE of centrifugal pumps aboard tank vessels?
They are gravity fed
Which pump must always be primed?
Centrifugal pump
The valve on the discharge side of a cargo pump on a tank vessel will usually be a __________.
check valve
To insure proper seating when closing a valve on a tank, the valve should be __________.
closed, opened half a turn, and then closed again
Centrifugal pumps have what advantage(s) over reciprocating pumps?
They are less expensive
They are smaller for equivalent pumping ability
They pump more cargo in less time
What is the purpose of the relief valve of a cargo pump?
permits the return of cargo to the suction side of the pump
A deepwell pump is a type of __________.
centrifugal pump
All of the following steps are taken in starting a centrifugal pump.
Check the lubrication system
Vent the pump casing
Open the pump suction and discharge valves
What is NOT a step taken in starting a centrifugal pump?
set the relief valve
What is the purpose of pressure-vacuum relief valves?
To maintain a tank or void at atmospheric pressure
Cargo pump relief valves are piped to the __________.
suction side of pumps
A relief valve for a cargo pump is generally installed __________.
between the pump and discharge valves
The system of valves and cargo lines in the bottom piping network of a tanker that connects one section of cargo tanks to another section is called a __________.
crossover
A single fitting installed in a pipeline that either blanks off the pipe or allows a full flow passage of a liquid through the pipe is referred to as a __________.
spectacle flange
The main function of a stripping system is to __________.
discharge liquid left in the cargo tanks after the main pumps have discharged the bulk
What will NOT increase friction of a liquid flowing in a pipe and cause a loss of suction head?
slowing the pumping rate
The fitting at the end of a cargo line in a tank that allows suction to be taken close to the bottom of a tank is a __________.
bell-mouth
What is LEAST likely to be used to strip a cargo tank?
centrifugal pump
The pipe used to connect two separate piping systems on a tank vessel is known as a __________.
crossover
The piping that routes an oil cargo from the manifold directly to a cargo tank and serves only one tank is known as a __________.
tank drop
The main underdeck pipeline on a tankship is connected to individual tanks by __________.
branch lines
The piping that routes an oil cargo from the manifold to underdeck pipelines is known as a __________.
line drop
Which characteristic is an advantage of a butterfly valve as compared to a gate valve?
quick operation
Which characteristic is an advantage of a butterfly valve as compared to a gate valve?
easier operation
What is an advantage of a gate valve over a butterfly valve?
less frequent maintenance
Which method should be used to warm up the pump turbines prior to discharge?
Shut the discharge valve and run the pump at low speed
Which statement is TRUE concerning deep well self-priming pumps?
stripping systems are generally eliminated for the purposes of cargo handling
Insulating flanges minimize the dangers arising from __________.
accumulations of electro static charges
You have completed a crude oil wash. What action should be taken with the oil in the lines running to the washing machines?
open a COW nozzle forward and one aft and drain the line into the after tank by gravity
When cleaning a tank by the Butterworth process, you should begin to pump out the slops __________.
when the process is started
When cleaning cargo tanks with portable machines, how is the machine grounded?
The water supply hoses contain internal wires that act as conductors
You are cleaning the tanks after carrying a cargo of crude oil. Which statement is TRUE?
steam cleaning and water washing are both capable of generating electro static charges within a tank
You are planning to use a crude oil washing system. What precaution must be taken with the source tank for the washing machines?
at least one meter must be decanted from the source tank
You are planning to use the crude oil washing system on your tankship. What is required to prevent electrostatic buildup in the tanks?
The source tank for the tank cleaning machines must have at least one meter decanted from it
You have water washed your cargo tanks using the fixed machines. What should you do before using portable machines to clean areas screened from the wash of the fixed machine by structural members?
ventilate the tank to eliminate any electrostatically charged mist
In order to reduce the accumulation of static electricity while loading petroleum products, you should __________.
start to load slowly
Static electricity may be built up by the __________.
Spraying or splashing of petroleum
Settling of solids or water in petroleum
Flow of petroleum through pipes
Which product is most likely to accumulate static electricity?
lubricating oil
The complete details of a crude oil washing system aboard your vessel, including the operating sequences and procedures, design characteristics, a description of the system, and required personnel will be found in the __________.
Crude Oil Washing Operations and Equipment Manual
When tank cleaning with a portable machine, the weight of the machine is suspended from __________.
the supply hose
Before a tank is to be crude oil washed, the oxygen content in the tank must be measured at a position __________.
one meter from the deck
What is NOT a requirement for the safe and effective use of a crude oil washing system?
Use portable washing machines to reach areas obscured by structural members in the tanks
What are requirements for the safe and effective use of a crude oil washing system?
Strip all tanks and remove the bottom residue
Use an inert gas system while washing tanks
Decant one meter from the source tank fro the tank cleaning machines
Which step is NOT generally taken when gas-freeing a tank?
application of degreasing solvents
Reid vapor pressure is __________.
a measurement of the amount of flammable vapors given off by a liquid at a certain temperature
The standard unit of liquid volume used in the petroleum industry, as well as the tanker industry, is a __________.
barrel
Ullages on tankers are measured from __________.
an above-deck datum such as the top of the ullage pipe
Argon is classified as a __________.
nonflammable gas
Camphor oil is classified as a grade __________.
D
Which statement concerning castor oil is TRUE?
It is a grade E combustible
Flame screens are used to __________.
prevent flames from entering tanks
Flammable liquid means any liquid which gives off flammable vapors at or below __________.
80F (26.7 C)
Flammable liquids should have what kind of label?
red
For the purpose of regulating tank vessels, flammable liquids are liquids which will __________.
give off flammable vapors at or BELOW 80* F (27* C)
Nonflammable gases should have what kind of label?
green
Containers of flammable solids should be conspicuously labeled by the shipper with a __________.
red and white lable
Most crude oils are classified as grade __________.
C or D
The lowest temperature at which a liquid will give off sufficient vapors to form a flammable mixture with air is known as the __________.
flash point
With an increase in temperature the volume of flammable and combustible liquids __________.
expands
Which refers to the depth of a petroleum product in a tank?
Innage
A flammable liquid having a Reid vapor pressure of 8½ P.S.I.A. or less and a flash point of 80°F or below is grade __________.
C
A petroleum liquid has a flash point of 135°Fahrenheit. This liquid is classed as a grade __________.
D combustible liquid
A petroleum liquid has a flash point of 85°F. This is a grade __________.
D combustible liquid
Combustible liquid is defined as any liquid having a flash point above __________.
80F (27C)
Combustible liquids are divided into how many grades?
Two
Grade D combustible liquids have a maximum flash point of __________.
149*F
Grade E combustible liquids have a flash point of __________.
150*F or above
A combustible liquid with a flash point of 90°F would be grade __________.
D
The designations A, B, C, D, and E grades of cargo refer to the __________.
flash point range and Reid vapor pressure index of petroleum products
A standard net barrel of petroleum products is __________.
42 gallons at 60* F
What is meant by “thieving” a petroleum cargo?
Determining the amount of water (if any) in each cargo tank
What is the standard net barrel for petroleum products?
42 gallons at 60*Fahrenheit
What refers to the depth of a petroleum product in a tank?
Innage
The distance between the surface of the liquid and the tank top in a cargo tank is called __________.
ullage
The explosive range of a fuel lies between the lower explosive limit and the __________.
upper explosive limit
The minimum temperature required to ignite gas or vapor without a spark or flame being present is called __________.
autoignition temperature
The (auto)ignition temperature is that temperature at which __________.
no spark or flame is required to ignite gas or vapor
A “barrel” is a unit of liquid measure equivalent to __________.
42 U.S. gallons at 60*F
Ullage measurements are taken from the top of the liquid to __________.
an above deck datum, usually the top of the ullage hole
Ullages are measured from __________.
an above deck datum
Sour crude oil __________.
contains high quantities of hydrogen sulfide
The vapor pressure of a substance __________.
increases with the temperature
Cargo transfer operations on a tank vessel need NOT be stopped when __________.
a tug comes alongside while the tanker is loading grade D and E cargoes
When loading a tanker, you should __________.
close valves by closing them down, reopening one or two turns, and re-closing
When loading bulk liquid cargo, what is the FIRST action you should take if a cargo valve jammed open?
order the dock man to shut down
Which factor must be considered when determining the order of loading of dissimilar products through the same piping system aboard a tanker?
contamination of the cargo
Which tanker discharge pattern would be the safest and most efficient?
Start discharging with most of the discharge coming from forward, but include some from midships and after tanks
While discharging a cargo, the stripping of the tanks falls behind schedule. This would indicate the __________.
main pumps are leaving too much oil in the tanks
While discharging a tanker, list can be controlled by __________.
using wing tanks near the longitudinal center, discharging as necessary
Your tank vessel is fully loaded, and you find that she is down slightly by the head. To adjust the trim, you may __________.
shift cargo aft
Your tank vessel is loaded down to her marks, and you find that she has too much trim by the stern. To adjust the trim you may __________.
shift bunkers forward
Your vessel is taking on cargo oil when a small leak develops in the hose. You order the pumping stopped. Before you resume pumping, you should __________.
replace the hose
The terminal indicates to you that they are going to use a booster pump to assist the discharging operation. You start the discharge and in a few minutes the pressure drops sharply. This could be a result of the __________.
booster pump coming on the line and discharging properly
When hooking up a cargo hose to your vessel’s manifold, you should use a(n) __________.
insulating flange or single length of non-conducting hose
Pinching of the cargo hose between the vessel and the dock should be prevented by __________.
adjusting the hose supports
To allow for the rise or fall in tide and for change in draft of a tankship during cargo transfer, cargo hoses must be suspended with __________.
enough slack in their bight
What is NOT a precaution to be taken when topping off?
notify the engine room of the procedure
Petroleum cargo tanks should not be topped off at deck level when loading on a cold day because __________.
a subsequent temperature rise will cause the cargo to overflow
Litmus paste is used in order to determine __________.
thievage
If you are bunkering and you close off one tank in the line of tanks being filled, the rate of flow to other open tanks on the same line will __________.
increase
Oil product samples should be taken from the __________.
Dock riser
Ship’s cargo tanks
Shore tank discharge
When discharging an oil cargo, the first consideration is to __________.
get the bow up
When measuring the oxygen content of the cargo tanks prior to loading cargoes requiring vapor recovery, check it __________.
one half the ullage of the tank and one meter below the tank top
When planning the loading or discharging of a VLCC (100,000 DWT+) what is the most important consideration?
limits of the bending moments
Which statement is TRUE concerning insulating flanges?
They should be inspected and tested periodically to ensure that the insulation is clean and in good condition
Functions aboard a tanker or tank barge such as connecting, disconnecting, and topping off must be supervised by _________
the person designated as “the person in charge”
Oil may NOT be transferred unless __________.
discharge containment equipment (i.e. drip pans) are in place
In controlling pollution, which action should be taken after all dirty ballast has been transferred to the slop tank and prior to discharge through the oily water separator?
The slops should be allowed time to settle
Which statement is TRUE concerning protection of double bottom tanks against excessive pressure?
The total area of the vents or the overflow shall be at least 125% of the area of the fill line
The most likely time for oil pollution while bunkering is when __________.
final topping off is occuring
When bunkering is complete, the hoses should be __________.
drained, blanked off, and stored securely
Which statement is FALSE concerning precautions during fueling operations?
fuel tanks should be topped off with no room for expansion
Which statements are TRUE concerning precautions during fueling operations?
All engines, motors, fans, etc. should be shut down when fueling
All windows, doors, hatches, etc. should be closed
A fire extinguisher should be kept nearby
You are on a vessel that carries liquefied gasses in bulk. The person on watch is required to have what information about the cargo easily accessible?
firefighting procedures
The Master must maintain the Oil Record Book on board for at least __________.
36 months
The oil record book is required to be carried aboard __________.
Tankers
Passenger vessels
Cargo vessels
The Oil Record Book on a vessel NOT engaged on a foreign voyage shall be maintained on board for not less than __________.
36 months
When oil is discharged overboard, an entry is required in the __________.
Oil Record Book
When oily ballast has been pumped overboard, an entry must be made in the __________.
Oil Record Book
While your vessel is docked port side to a wharf, a sudden gale force wind causes the vessel’s stern lines to part. The stern begins to fall away from the dock, and no tugs are immediately available. Which measure(s) should you take FIRST?
shut down any cargo transfer that’s in process
You start a centrifugal cargo pump to discharge cargo. The pump works for a while and then loses suction. This could be caused by __________.
incomplete priming
You start a centrifugal cargo pump to discharge cargo. The pump works for a while and then loses suction. This could NOT be caused by __________.
high cargo level in the tanks
You may be able to avoid loss of suction in a pump by __________.
Using a full tank to keep the pump primed
Opening the vent cock on the pump
Closing down on the tank valve
