WorksheetsWhy do we need to study about pumps?
Total questions: 86
Worksheet time: 43mins
Pumps are an integral _______ equipment common to all ships.
auxiliary
primary
navigation
communication
Which of the following is NOT a use of pumps on ships?
Used in engine room
Used in main engine
Used in generator engine systems
Used for cooking food
Pumps are essential in case of emergencies like flooding and fires.
True
False
Explain the purpose of Marine pumps and describe the types of other pumps used on board ships.
Marine pumps are used for transferring fluids and include types such as centrifugal, reciprocating, screw, and gear pumps.
Marine pumps are only used for air circulation and include only centrifugal pumps.
Marine pumps are used for electrical generation and include only gear pumps.
Marine pumps are used for navigation and include only reciprocating pumps.
Discuss the construction, operation and application of rotary displacement pumps, gear pumps, screw pumps and rotary vane pumps.
Rotary displacement pumps include gear, screw, and rotary vane pumps, each with unique construction and operation suited for specific applications.
Rotary displacement pumps are only used for water supply and do not include gear or screw pumps.
Gear pumps and screw pumps are not types of rotary displacement pumps.
Rotary vane pumps operate identically to centrifugal pumps and have no unique construction.
The purpose and function of components of a centrifugal pump are:
To convert mechanical energy into hydraulic energy and move fluids efficiently.
To generate electricity from water flow.
To filter impurities from liquids.
To measure the pressure of fluids in a system.
The characteristic of a centrifugal pump with respect to suction lift, priming, discharge pressure, and vapour in liquid is:
It requires priming, has limited suction lift, moderate discharge pressure, and can be affected by vapour in liquid.
It does not require priming, has unlimited suction lift, high discharge pressure, and is not affected by vapour in liquid.
It requires no priming, has low suction lift, low discharge pressure, and is unaffected by vapour in liquid.
It requires priming, has high suction lift, high discharge pressure, and is not affected by vapour in liquid.
Applying knowledge of pumping systems, which of the following best describes how to conduct maintenance checks on submersible pumps, mono pumps, variable delivery pumps, and swash plate pumps?
Inspect for leaks, check electrical connections, monitor vibration, and ensure proper lubrication.
Only check the pump's exterior for dirt and dust.
Run the pumps at maximum speed to test durability.
Ignore electrical connections and focus only on mechanical parts.
Identify the correct sequence of steps to troubleshoot displacement and centrifugal pumps.
Check for leaks, inspect for blockages, verify power supply, and test pump operation.
Replace the pump immediately without inspection.
Ignore unusual noises and continue operation.
Increase the pump speed without checking for issues.
The purpose and requirement of the bilge pumping system, emergency bilge suction, emergency fire pump, and ballast pumping system are:
To remove unwanted water, provide emergency dewatering, supply water for firefighting, and manage ship stability.
To generate electricity, control engine speed, and monitor fuel consumption.
To provide ventilation, control temperature, and manage waste disposal.
To store cargo, maintain crew quarters, and operate navigation systems.
What is one function of a pump?
Transfer fluid between two points.
Generate electricity.
Measure temperature.
Store solid materials.
What is another function of a pump?
Produce required flow rate.
Generate electricity.
Measure temperature.
Store energy.
What is another function of a pump?
Produce required pressure.
Generate electricity.
Store fuel.
Measure temperature.
In the diagram of the pump, which side is labeled as 'suction'?
Top
Bottom
Left
Right
A pump changes both ______ and pressure of the fluid.
velocity
temperature
color
density
A pump only adds to the system energy.
True
False
Power supplied to the pump is to transfer fluid at specified flow rate and pressure by overcoming ______ in the pump and the system.
resistance
temperature
velocity
density
A pump creates pressure and provides flow.
True
False
Viscosity of the fluid pumped must be within the range ______ specified in the pump design.
specified
measured
expected
observed
Which type of pump can handle any required viscosity?
Centrifugal Pumps
Reciprocating Displacement Pumps
Rotary Positive Displacement Pumps
None of the above
Rotary Positive Displacement Pumps (Common- Gear and Screw) are used for ______ range of viscosities.
intermediate
low
high
very high
Centrifugal Pumps are used for which range of viscosities?
High
Medium to Low
Intermediate
Any
Onboard ships, permission should be obtained before any fluids are moved, which might affect the stability of the ship.
True
False
One use of pumps onboard ship is the transfer of ___
Transfer of oil and other fluids from tanks, machinery or other equipment
Electrical signals between control panels
Passengers between decks
Cargo using conveyor belts
One use of pumps onboard ship is ___ .
Cargo operation (discharging cargo in tankers)
Navigating the ship
Operating the radar
Cooking food
One use of pumps onboard ship is ___ .
Ballasting operation
Cooking food
Navigating the ship
Operating the radar
One use of pumps onboard ship is ___.
Fire fighting
Cooking food
Navigating the ship
Operating the radar
One use of pumps onboard ship is to pump out seawater in case of vessel ingress.
Pump out seawater in case of vessel ingress
Start the ship's engine
Navigate the ship
Operate the ship's radar
One use of pumps onboard ship is ___ .
Oil spill prevention
Cooking food
Navigating the ship
Operating the radar
What is the full form of NPSH?
Net Positive Suction Head
Negative Pressure Suction Head
Nominal Pump Suction Height
Normal Pressure Supply Head
Why is the Net Positive Suction Head (NPSH) margin important when selecting a pump?
It is a crucial factor that is commonly overlooked while selecting a pump.
It determines the color of the pump.
It affects the electrical wiring of the pump.
It is only relevant for pumps used in chemical industries.
What is the difference between NPSHa and NPSHr?
NPSHa is the Net Positive Suction Head available at the pump’s inlet, and NPSHr is the Net Positive Suction Head required by the pump to operate without cavitation.
NPSHa is the Net Positive Suction Head required by the pump, and NPSHr is the Net Positive Suction Head available at the pump’s inlet.
NPSHa and NPSHr are both the same and refer to the pressure at the pump outlet.
NPSHa is the Net Positive Suction Head at the discharge side, and NPSHr is at the suction side.
Cavitation is the formation of ______ at the pump inlet, followed by their sudden collapse, which can cause permanent damage.
bubbles
crystals
solids
fibers
The NPSH margin value must be ______ to avoid cavitation.
negative
zero
positive
very high
What phenomenon is shown damaging the metal surface?
Corrosion
Cavitation
Erosion
Fatigue
Using the diagram on the right, cavitation in mechanical systems is:
The formation of vapor bubbles in a liquid due to a drop in pressure, which can cause damage when they collapse.
The process of lubricating moving parts to reduce friction.
The increase in fluid pressure leading to improved system efficiency.
The accumulation of solid particles in a fluid causing blockages.
Considering the total energy of a fluid moving, every time a fluid increases its velocity its pressure _________.
decreases
increases
remains constant
becomes zero
What does the relationship between velocity and pressure produce with respect to hydraulic machinery, pipes, and hydraulic structures?
Welcome effects
Unwelcome effects
No effects
Positive effects
These problems arise when the absolute pressure falls sufficiently for the small quantity of air that is dissolved in the water to be released followed by local vaporization of the liquid. What is this process called?
Sublimation
Cavitation
Condensation
Precipitation
What happens to these bubbles when pressure increases?
They implode.
They expand.
They float to the top.
They multiply.
One of the factors affecting suction lift is ________ and volatility of the fluid.
Temperature
Pressure
Density
Viscosity
One of the factors affecting suction lift is pressure exerted on the ________ side of the liquid.
free
inlet
discharge
vacuum
One of the factors affecting suction lift is friction losses at entrances, bends and ________ in the suction system.
pipes
valves
tanks
motors
What is a prime mover? A prime mover is a term for a machine or device that converts other forms of energy into ________ mechanical energy.
rotational
thermal
chemical
electrical
Which of the following is a type of pump prime mover?
Electric motor
Solar panel
Wind turbine
Steam engine
Which of the following is NOT listed as a type of pump prime mover?
Hydraulic motor
Pneumatic
Gasoline engine
Electric motor
The three types of pump prime movers mentioned in the passage are:
Electric motor, internal combustion engine, steam turbine
Hydraulic ram, windmill, solar panel
Diesel generator, pneumatic actuator, hydraulic press
Gas turbine, centrifugal fan, reciprocating compressor
According to the passage, why might it be desirable to use two or more pumps operating together instead of one large machine?
There are circumstances where it may be desirable to use two or more pumps operating together instead of one large machine.
It is always more efficient to use a single large machine for pumping.
Using multiple pumps is never recommended in any situation.
Two or more pumps are only used when the passage specifically prohibits large machines.
Which of the following is NOT one of the three choices for pump operation mentioned in the passage?
Single machine
Pumps in series
Pumps in parallel
Pumps in sequence
The three choices for pump operation mentioned are Single machine, Pumps in series, and ________.
Pumps in parallel
Pumps in reverse
Pumps in cascade
Pumps in isolation
Why is it preferable to use several small machines operating at peak efficiency in a combination of pumps?
Because the required discharge varies over a wide range hence it is preferable to use several small machines operating at the peak efficiency.
Because small machines are easier to maintain than large machines.
Because small machines consume less power than large machines.
Because small machines are less expensive than large machines.
What does it mean if Q and H are out of the range of the individual machine in the context of pump combinations?
It means that the required flow rate (Q) and head (H) cannot be achieved by a single pump, so a combination of pumps is used.
It means the pump is operating at maximum efficiency.
It means the pump is not connected to a power source.
It means the pump is suitable for all types of fluids.
What is the advantage of splitting the duty between several pumps if the pump is in continuous use?
Splitting the duty between several pumps allows one to be on standby to provide emergency backup in the event of a breakdown, and for planned maintenance.
Splitting the duty between several pumps increases the risk of simultaneous breakdowns.
Splitting the duty between several pumps reduces the overall efficiency of the system.
Splitting the duty between several pumps makes maintenance more difficult and time-consuming.
Each pump in a series configuration has its own _____
motor
pipe
valve
filter
In a series configuration, both pumps are fitted to the same suction and delivery pipes, meaning the same water passes through each of the pumps in turn.
True
False
For pumps in series, Q is the same as a single pump but the head is _____
doubled
halved
unchanged
reduced
What is one advantage of using pumps in series (P+P)?
We can cover a high range of H.
The system never fails.
It reduces friction losses.
It increases the number of pumps required.
If one pump in a series system breaks, the ______ system fails.
whole
partial
backup
parallel
What is the formula for the specific speed (Ns) for each unit in series?
(H/n)3/4NQ
H3/4NQ
Ns=H1/2NQ
Ns=H5/4NQ2
If friction consists the major part of the system curve, series operations provide more capacity.
True
False
Refer to the diagram showing 'Pumps in series (P+P)'. What is the effect on the head (h_a) when two pumps are placed in series compared to one pump?
The head (h_a) increases when two pumps are placed in series compared to one pump.
The head (h_a) decreases when two pumps are placed in series compared to one pump.
The head (h_a) remains the same when two pumps are placed in series compared to one pump.
The head (h_a) becomes zero when two pumps are placed in series compared to one pump.
Refer to the diagram showing 'Pumps in series (P+P)'. At which point, (A) or (B), is the system operating with two pumps in series?
Point (A)
Point (B)
Refer to the diagram showing 'Pumps in series (P+P)'. True or False: Placing two pumps in series increases the flowrate at the same system head compared to a single pump.
True
False
Which statement is true about pumps in parallel?
Each pump has its own suction pipe but delivers into a common delivery pipe.
Each pump shares a suction pipe and delivers into separate delivery pipes.
All pumps share both suction and delivery pipes.
Each pump operates independently without any shared pipes.
The head obtained from two pumps in parallel is the same as for a single pump, but the ______ is doubled.
discharge
head
efficiency
power
How can the H-Q curve be obtained for pumps in parallel?
By doubling Q for a particular H.
By doubling H for a particular Q.
By halving Q for a particular H.
By halving H for a particular Q.
Pumps in parallel may be the best arrangement when _____ is relatively constant but _____ varies over a wide range.
H; Q
Q; H
P; V
V; P
If the static head component is a large portion of the system total head and friction losses are low, pumps in parallel provide more _____
capacity
pressure
efficiency
temperature
The specific speed of each unit is _____ = N∗Q/n/H3/4 .
Ns
Np
Nr
Nt
When two pumps are operated in parallel (P//P), the flowrate compared to a single pump:
increases significantly
decreases
remains the same
becomes zero
Refer to the diagram showing pumps in parallel (P//P). At which point, A or B, is the system operating with two pumps in parallel?
Point A
Point B
Which of the following is increased by pumps in SERIES?
Flowrate
Total dynamic head (Pressure)
Temperature
Total volume transferred
Pumps in PARALLEL increase the ________ (i.e. Total volume transferred by the pump).
flowrate
pressure
temperature
efficiency
What is the main function of the impeller in a centrifugal pump?
To increase water pressure
To rotate radial vanes and draw water into the center
To discharge water by gravity
To filter water
The most commonly used pumps in water supply systems are ________ pumps.
centrifugal
reciprocating
gear
peristaltic
The common feature of all centrifugal pumps is the Volute.
True
False
Look at the diagram. Identify the type of mechanical component shown in the image.
Gear
Pulley
Lever
Spring
Refer to the diagram labeled 'DISMANTLING (PUMP WITH PACKING)'. What is the location of the dowel pin at the parting line called?
A
B
C
D
What is the dimension 'A' for pump size 2 x 3-11?
9.755
8.500
10.200
12.000
What is the packing size for pump size 4 x 6-10?
12
10
14
16
What is the dimension 'A' for pump size 8 x 10-17?
11.495
10.250
12.000
13.750
Is internal piping with seal cage optional?
True
False
A pump changes both _______ and pressure of the fluid.
velocity
temperature
density
color
Pump only adds to the system _______.
energy
pressure loss
friction
temperature
Power supplied to the pump is to transfer fluid at specified flow rate and pressure by overcoming _______ in the pump and the system.
resistance
temperature
velocity
density
A pump creates pressure in the system.
True
False
