Pick up the correct statement from the following regarding radial flow centrifugal pumps: (A) These are provided with volute type or turbine type casings (B) In involute type of radial flow centrifugal pump, the impeller discharges into a gradually expanding spiral casing (C) The efficiency of turbine type of radial flow centrifugal pump, is always higher than that of volute type (D) All the above

Pick up the correct statement from the following regarding radial flow centrifugal pumps: 

(A) These are provided with volute type or turbine type casings 

(B) In involute type of radial flow centrifugal pump, the impeller discharges into a gradually 

expanding spiral casing 

(C) The efficiency of turbine type of radial flow centrifugal pump, is always higher than that of 

volute type 

(D) All the above 

by

1 Answer

Answer :

(D) All the above 

by

Related questions

Which of the following is not the function of a volute casing provided in a centrifugal pump? (A) To reduce the head loss in discharge (B) To increase the pump efficiency (C) To collect liquid from the periphery of the impeller and to transmit it to the delivery pipe at constant velocity (D) To increase the pump discharge rate

Description : Which of the following is not the function of a volute casing provided in a centrifugal pump? (A) To reduce the head loss in discharge (B) To increase the pump efficiency (C) To collect liquid ... and to transmit it to the delivery pipe at constant velocity (D) To increase the pump discharge rate

Last Answer : Option D

A centrifugal pump is called a turbine pump, if it is having a (A) Turbine type impeller (B) Vaned diffusion casing (C) Rotating vaned volute (D) None of these

Description : A centrifugal pump is called a turbine pump, if it is having a (A) Turbine type impeller (B) Vaned diffusion casing (C) Rotating vaned volute (D) None of these

Last Answer : (B) Vaned diffusion casing

A mixed flow centrifugal pump (A) Employs such an impeller, through which the flow is a combination of radial & axial flow (B) Mixes the two fluids before pumping them (C) Pumps the two fluids separately and then mixes them (D) Employs impellers in both the radial & axial directions

Description : A mixed flow centrifugal pump (A) Employs such an impeller, through which the flow is a combination of radial & axial flow (B) Mixes the two fluids before pumping them (C) Pumps the two fluids separately and then mixes them (D) Employs impellers in both the radial & axial directions

Last Answer : (A) Employs such an impeller, through which the flow is a combination of radial & axial flow

Volute type of casing is provided in a centrifugal pump to (A) Convert velocity head to pressure head (B) Convert pressure head to velocity head (C) Reduce the discharge fluctuation (D) Increase the discharge

Description : Volute type of casing is provided in a centrifugal pump to (A) Convert velocity head to pressure head (B) Convert pressure head to velocity head (C) Reduce the discharge fluctuation (D) Increase the discharge

Last Answer : (D) Increase the discharge

In centrifugal compressor terminology, vaneless space refers to the space between A. The inlet and blade inlet edge B. Blades in the impeller C. Diffuser exit and volute casing D. Impeller tip and diffuser inlet edge

Description : In centrifugal compressor terminology, vaneless space refers to the space between A. The inlet and blade inlet edge B. Blades in the impeller C. Diffuser exit and volute casing D. Impeller tip and diffuser inlet edge

Last Answer : ANSWER : D

Design of the casing of centrifugal pump should be such as to minimise the (A) Back flow through impeller (B) Loss of kinetic head (C) Loss of static head (D) None of these

Description : Design of the casing of centrifugal pump should be such as to minimise the (A) Back flow through impeller (B) Loss of kinetic head (C) Loss of static head (D) None of these

Last Answer : (B) Loss of kinetic head

Which of the following options will facilitate the achievement of a very high head (say 30 metres) in case of a centrifugal pump? (A) Increasing the impeller speed and the volute area (B) Increasing the number of vanes in the impeller (C) Mounting of two or more impellers in series on a single shaft (D) Either of (A), (B) or (C)

Description : Which of the following options will facilitate the achievement of a very high head (say 30 metres) in case of a centrifugal pump? (A) Increasing the impeller speed and the volute area (B) Increasing the number of vanes ... or more impellers in series on a single shaft (D) Either of (A), (B) or (C)

Last Answer : (C) Mounting of two or more impellers in series on a single shaft

Volute of a centrifugal pump should be designed in a fashion, such that the (A) Kinetic head gets converted into static head (B) Moving stream gradually reduces velocity (C) Mean velocity remains constant (D) None of these

Description : Volute of a centrifugal pump should be designed in a fashion, such that the (A) Kinetic head gets converted into static head (B) Moving stream gradually reduces velocity (C) Mean velocity remains constant (D) None of these

Last Answer : (A) Kinetic head gets converted into static head

Conversion of dynamic velocity head into static pressure head in a centrifugal pump is the result of : (a) Increasing area of flow between adjacent vanes from inlet to outlet (b) Difference in pressure between suction and delivery ends (c) Radial thrust in pumps (d) Stuffing Box

Description : Conversion of dynamic velocity head into static pressure head in a centrifugal pump is the result of : (a) Increasing area of flow between adjacent vanes from inlet to outlet (b) Difference in pressure between suction and delivery ends (c) Radial thrust in pumps (d) Stuffing Box

Last Answer : (b) Difference in pressure between suction and delivery ends

Centrifugal pump is normally classified on the basis of the (A) rpm (B) Type of casing (C) Impeller blade angle (D) Number of blades in impeller

Description : Centrifugal pump is normally classified on the basis of the (A) rpm (B) Type of casing (C) Impeller blade angle (D) Number of blades in impeller

Last Answer : (B) Type of casing

The capacity of a centrifugal pump Can be increased by increasing the (A) Impeller diameter or speed (B) Number of pumps and joining them in series (C) Number of pumps and joining them in parallel (D) All (A), (B) and (C)

Description : The capacity of a centrifugal pump Can be increased by increasing the (A) Impeller diameter or speed (B) Number of pumps and joining them in series (C) Number of pumps and joining them in parallel (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Which one of the following statements is correct? A. Reciprocating compressors are used to supply large quantities of air at a lower pressure ratio B. Centrifugal compressors are used to supply large quantities of air at a lower pressure ratio C. Centrifugal compressors are used to supply small quantities of air at a lower pressure ratio D. Centrifugal compressors cannot be run at high speed because of impeller, diffuser and casing.

Description : Which one of the following statements is correct? A. Reciprocating compressors are used to supply large quantities of air at a lower pressure ratio B. Centrifugal compressors are used to supply ... . Centrifugal compressors cannot be run at high speed because of impeller, diffuser and casing.

Last Answer : ANSWER : B

To handle smaller quantity of fluid at higher discharge pressure, use a __________ pump. (A) Reciprocating (B) Centrifugal (C) Volute (D) Rotary vacuum

Description : To handle smaller quantity of fluid at higher discharge pressure, use a __________ pump. (A) Reciprocating (B) Centrifugal (C) Volute (D) Rotary vacuum

Last Answer : (A) Reciprocating

Higher specific speed (200-500) of a centrifugal pump indicates that the pump is of __________ flow type. (A) Axial (B) Radial (C) Mixed (D) None of these

Description : Higher specific speed (200-500) of a centrifugal pump indicates that the pump is of __________ flow type. (A) Axial (B) Radial (C) Mixed (D) None of these

Last Answer : (A) Axial

In case of a centrifugal pump, the ratio of total delivered pressure to pressure developed with the impeller is called the __________ efficiency. (A) Manometric (B) Mechanical (C) Volumetric (D) Overall

Description : In case of a centrifugal pump, the ratio of total delivered pressure to pressure developed with the impeller is called the __________ efficiency. (A) Manometric (B) Mechanical (C) Volumetric (D) Overall

Last Answer : (A) Manometric

In case of a, centrifugal pump, the ratio h1/h2is termed as the __________ efficiency (where, h1 = actual measured head & h2 = head imparted to the fluid by impeller). (A) Mechanical (B) Overall (C) Volumetric (D) Impeller

Description : In case of a, centrifugal pump, the ratio h1/h2is termed as the __________ efficiency (where, h1 = actual measured head & h2 = head imparted to the fluid by impeller). (A) Mechanical (B) Overall (C) Volumetric (D) Impeller

Last Answer : A) Mechanical

Most commonly used pump for lifting water in water supply mains, is (A) Axial flow pump (B) Reciprocating pump (C) Rotary type pump (D) Centrifugal pumps

Description : Most commonly used pump for lifting water in water supply mains, is  (A) Axial flow pump  (B) Reciprocating pump  (C) Rotary type pump  (D) Centrifugal pumps 

Last Answer : (A) Axial flow pump 

Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B) The co-efficient of contraction of a Venturimeter is always unity (C) For a fixed pressure drop, the discharge of a gas through a Venturimeter is greater, when compressibility is taken into account, than when it is neglected (D) None of these

Description : Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B ... , when compressibility is taken into account, than when it is neglected (D) None of these

Last Answer : (D) None of these

In centrifugal pumps, cavitation occurs, when pressure of the impeller eye or vane becomes (A) Less than atmospheric pressure (B) More than liquid vapor pressure (C) Less than liquid vapor pressure (D) More than atmospheric pressure

Description : In centrifugal pumps, cavitation occurs, when pressure of the impeller eye or vane becomes (A) Less than atmospheric pressure (B) More than liquid vapor pressure (C) Less than liquid vapor pressure (D) More than atmospheric pressure

Last Answer : (C) Less than liquid vapor pressure

The type of pump used for the recirculation of molten sodium coolant in liquid metal cooled reactor is a/an __________ pump. (A) Electromagnetic (B) Reciprocating (C) Centrifugal (D) Volute

Description : The type of pump used for the recirculation of molten sodium coolant in liquid metal cooled reactor is a/an __________ pump. (A) Electromagnetic (B) Reciprocating (C) Centrifugal (D) Volute

Last Answer : (A) Electromagnetic

Priming of a centrifugal pump is done to (A) Increase the mass flow rate of fluid (B) Develop effective pressure rise by the pump (C) Avoid chances of separation inside the impeller (D) None of these

Description : Priming of a centrifugal pump is done to (A) Increase the mass flow rate of fluid (B) Develop effective pressure rise by the pump (C) Avoid chances of separation inside the impeller (D) None of these

Last Answer : (C) Avoid chances of separation inside the impeller

Which one of the following types of impeller vanes are most commonly used in centrifugal type compressors? A. Forward curved B. Radial C. Backward curved D. Tangential

Description : Which one of the following types of impeller vanes are most commonly used in centrifugal type compressors? A. Forward curved B. Radial C. Backward curved D. Tangential

Last Answer : ANSWER : C

Maintenance cost of a __________ pump for a particular duty is the least. (A) Centrifugal (B) Reciprocating (C) Volute (D) Gear

Description : Maintenance cost of a __________ pump for a particular duty is the least. (A) Centrifugal (B) Reciprocating (C) Volute (D) Gear

Last Answer : (A) Centrifugal

Turbine impeller (A) Produces only radial current (B) Produces only tangential current (C) Is effective over wide range of viscosities (D) Does not produce tangential current

Description : Turbine impeller (A) Produces only radial current (B) Produces only tangential current (C) Is effective over wide range of viscosities (D) Does not produce tangential current

Last Answer : (C) Is effective over wide range of viscosities

Reciprocating pumps are not able to compete with the centrifugal pump for industrial use, mainly because these pumps have (A) Very low speeds (B) Smaller discharge (C) Higher capital &maintenance cost (D) High vibrations

Description : Reciprocating pumps are not able to compete with the centrifugal pump for industrial use, mainly because these pumps have (A) Very low speeds (B) Smaller discharge (C) Higher capital &maintenance cost (D) High vibrations

Last Answer : (C) Higher capital &maintenance cost

Which is the correct relationship for a centrifugal pump? (Where, D = Impeller diameter, inches H = Head developed, ft of liquid pumped N = Speed of pump, rpm) (A) D = 1840 H0.5 /N (B) D = 1840 N/H0.5 (C) H = 1840 D0.5 /N (D) D = 1840 H/N

Description : Which is the correct relationship for a centrifugal pump? (Where, D = Impeller diameter, inches H = Head developed, ft of liquid pumped N = Speed of pump, rpm) (A) D = 1840 H0.5 /N (B) D = 1840 N/H0.5 (C) H = 1840 D0.5 /N (D) D = 1840 H/N

Last Answer : (A) D = 1840 H0.5 /N

Pick out the wrong statement pertaining to the turbine agitator. (A) Recommended peripheral speed for the turbine agitator is 200-250 metres/minute (B) Pitched blade turbine agitator gives only radial flow with complete absence of the axial flow (C) Generally, the diameter of the agitator is kept between l/3rd to l/6th of the tank diameter while the blade length is l/4th of agitator diameter (with central disc, it is l/8th of the agitator diameter)

Description : Pick out the wrong statement pertaining to the turbine agitator. (A) Recommended peripheral speed for the turbine agitator is 200-250 metres/minute (B) Pitched blade turbine agitator gives only radial flow with ... l/4th of agitator diameter (with central disc, it is l/8th of the agitator diameter)

Last Answer : (B) Pitched blade turbine agitator gives only radial flow with complete absence of the axial flow

The depth of the water table at a place is 45 m below the general ground level. To lift water from a deep tube well in such a locality, the type of pump to be installed is (A) Centrifugal pump (B) Reciprocating pump (C) Deep well turbine pump (D) None of these

Description : The depth of the water table at a place is 45 m below the general ground level. To lift water from a  deep tube well in such a locality, the type of pump to be installed is  (A) Centrifugal pump  (B) Reciprocating pump  (C) Deep well turbine pump  (D) None of these 

Last Answer : (C) Deep well turbine pump

The pump impeller and the turbine runner in a hydraulic torque converter (A) Have the same diameter (B) Have different diameters (C) Are directly coupled (D) None of these

Description : The pump impeller and the turbine runner in a hydraulic torque converter (A) Have the same diameter (B) Have different diameters (C) Are directly coupled (D) None of these

Last Answer : (B) Have different diameters

In case of a __________ the energy of flow is considerably decreased downstream of the machine. (A) Blower (B) Turbine (C) Centrifugal pump (D) Centrifugal fan

Description : In case of a __________ the energy of flow is considerably decreased downstream of the machine. (A) Blower (B) Turbine (C) Centrifugal pump (D) Centrifugal fan

Last Answer : (B) Turbine

Most of the centrifugal pumps used in chemical plants are usually __________ driven. (A) Steam (B) Diesel engine (C) Electric motor (D) Gas turbine

Description : Most of the centrifugal pumps used in chemical plants are usually __________ driven. (A) Steam (B) Diesel engine (C) Electric motor (D) Gas turbine

Last Answer : (C) Electric motor

Consider a centrifugal pump having a specific impeller diameter, fixed impeller speed pumping a liquid of constant density at a particular discharge capacity. With decrease in the capacity of the pump, the __________ decreases. (A) NPSH required (B) BHP required by the pump (C) Head of the liquid pumped (D) All (A), (B) and (C)

Description : Consider a centrifugal pump having a specific impeller diameter, fixed impeller speed pumping a liquid of constant density at a particular discharge capacity. With decrease in the capacity of the pump, the __________ decreases. (A) ... the pump (C) Head of the liquid pumped (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

With a constant diameter impeller of a centrifugal pump (A) Its capacity varies directly as the square of speed (B) Head varies as the square of speed (C) Horsepower input varies as the square of speed (D) Head varies as the speed

Description : With a constant diameter impeller of a centrifugal pump (A) Its capacity varies directly as the square of speed (B) Head varies as the square of speed (C) Horsepower input varies as the square of speed (D) Head varies as the speed

Last Answer : (B) Head varies as the square of speed

Theoretical head developed by a centrifugal pump does not depend upon the __________ the impeller. (A) Radius of (B) Speed of (C) Fluid velocity leaving (D) None of these

Description : Theoretical head developed by a centrifugal pump does not depend upon the __________ the impeller. (A) Radius of (B) Speed of (C) Fluid velocity leaving (D) None of these

Last Answer : (D) None of these

Head developed by a centrifugal pump depends on its (A) Speed (B) Impeller diameter (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : Head developed by a centrifugal pump depends on its (A) Speed (B) Impeller diameter (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : C) Both (A) and (B)

At a constant speed of the centrifugal pump, it’s __________ the impeller diameter. (A) Capacity varies directly with (B) Head varies as the square of (C) Horsepower varies as the cube of (D) All (A), (B) and (C)

Description : At a constant speed of the centrifugal pump, it’s __________ the impeller diameter. (A) Capacity varies directly with (B) Head varies as the square of (C) Horsepower varies as the cube of (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

The head developed by a centrifugal pump is largely determined by the (A) Power of the pump(B) Nature of the liquid being pumped(C) Angle of the vanes and the speed of the tip of the impeller(D) Vapour pressure of the liquid

Description : The head developed by a centrifugal pump is largely determined by the (A) Power of the pump (B) Nature of the liquid being pumped (C) Angle of the vanes and the speed of the tip of the impeller (D) Vapour pressure of the liquid

Last Answer : (C) Angle of the vanes and the speed of the tip of the impeller

In case of a centrifugal pump, the theoretical head developed is dependent on the __________ the impeller. (A) Speed of (B) Diameter of (C) Fluid velocity leaving (D) All (A), (B) and (C)

Description : In case of a centrifugal pump, the theoretical head developed is dependent on the __________ the impeller. (A) Speed of (B) Diameter of (C) Fluid velocity leaving (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Erosion and pits formation on the impeller of a centrifugal pump may be due to (A) Cavitation (B) Low speed of impeller (C) Its operation with delivery valve closed for considerable time after starting the pump (D) Off centering of pump with motor

Description : Erosion and pits formation on the impeller of a centrifugal pump may be due to (A) Cavitation (B) Low speed of impeller (C) Its operation with delivery valve closed for considerable time after starting the pump (D) Off centering of pump with motor

Last Answer : (A) Cavitation

Good design of the casing of a centrifugal pump aims at minimising the (A) Cavitation (B) Frictional losses (C) Kinetic energy loss (D) Static head

Description : Good design of the casing of a centrifugal pump aims at minimising the (A) Cavitation (B) Frictional losses (C) Kinetic energy loss (D) Static head

Last Answer : Option C

For attaining maximum efficiency, a Francis turbine runner is so designed as to result in radial discharge at exit. This is done by : a) Providing runner vane angle at inlet as 90o b) Providing guide vane angle at inlet as 90o c) Providing runner vane angle at exit as 90o d) Designing for absolute velocity at outlet to be inclined at 90o to direction of vane there

Description : For attaining maximum efficiency, a Francis turbine runner is so designed as to result in radial discharge at exit. This is done by : a) Providing runner vane angle at inlet as 90o b) Providing ... 90o d) Designing for absolute velocity at outlet to be inclined at 90o to direction of vane there

Last Answer : d) Designing for absolute velocity at outlet to be inclined at 90o to direction of vane there

What is difference between Archimedian spiral and involute of a circle?

Description : What is difference between Archimedian spiral and involute of a circle?

Last Answer : answer:From Wolfram MathWorld article on Circle Involute Pedal Curve: The pedal curve of circle involute f = cos t + t sin t g = sin t - t cos t with the center as the pedal point is the ... . The two curves are compared in this image from Wikipedia (black = circle involute; red = A. spiral).

The locus of a point on a thread unwound from a cylinder will be a.A circle b.A cycloid c.A straight line d.A spiral e.An involute

Description : The locus of a point on a thread unwound from a cylinder will be a.A circle b.A cycloid c.A straight line d.A spiral e.An involute

Last Answer : b. A cycloid

Reciprocating pumps (A) Are not suitable for variable heads (B) Are four times costlier than centrifugal pumps (C) Are not suitable for pumping water containing sediments (D) Single stroke produce pulsating flow

Description : Reciprocating pumps  (A) Are not suitable for variable heads  (B) Are four times costlier than centrifugal pumps  (C) Are not suitable for pumping water containing sediments  (D) Single stroke produce pulsating flow 

Last Answer : (A) Are not suitable for variable heads 

Which of the following pumps in used to pump sewage solids with liquid sewage without clogging the pump is? A. Centrifugal pump B. Pneumatic ejector C. Reciprocating pump D. None of these

Description : Which of the following pumps in used to pump sewage solids with liquid sewage without clogging the pump is? A. Centrifugal pump B. Pneumatic ejector C. Reciprocating pump D. None of these

Last Answer : ANS: A

Propellers are (A) Axial flow mixers (B) Low speed impeller (C) Used for mixing liquids of high viscosity (D) Radial flow mixers

Description : Propellers are (A) Axial flow mixers (B) Low speed impeller (C) Used for mixing liquids of high viscosity (D) Radial flow mixers

Last Answer : (A) Axial flow mixers

__________ is an example of axial flow impeller. (A) Paddle (B) Turbine (C) Propeller (D) All (A), (B) and (C)

Description : __________ is an example of axial flow impeller. (A) Paddle (B) Turbine (C) Propeller (D) All (A), (B) and (C)

Last Answer : (C) Propeller

With increasing flow rate, the hydraulic efficiency of a centrifugal pump (A) Monotonically decreases (B) Decreases and then increases(C) Remains constant(D) Increases and then decreases

Description : With increasing flow rate, the hydraulic efficiency of a centrifugal pump (A) Monotonically decreases (B) Decreases and then increases (C) Remains constant (D) Increases and then decreases

Last Answer : (A) Monotonically decreases

Pick up the correct statement from the following: (A) At a particular speed of operation, the head produced decreases with the increase of discharge (B) At zero discharge, discharge valve remaining closed, the head developed is maximum which is known as shut-off head (C) At a particular speed the discharge at which efficiency of a pump is maximum, is known as normal discharge (D) All the above

Description : Pick up the correct statement from the following: (A) At a particular speed of operation, the head produced decreases with the increase of discharge (B) At zero discharge, discharge valve remaining closed ... which efficiency of a pump is maximum, is known as normal discharge (D) All the above

Last Answer : (D) All the above

Check valve provided in the discharge line of a centrifugal pump serves the purpose of controlling the (A) Back flow of fluid in the event of stoppage of pump (B) Discharge pressure (C) Flow of liquid during operation of the pump (D) All (A), (B) and (C)

Description : Check valve provided in the discharge line of a centrifugal pump serves the purpose of controlling the (A) Back flow of fluid in the event of stoppage of pump (B) Discharge pressure (C) Flow of liquid during operation of the pump (D) All (A), (B) and (C)

Last Answer : (A) Back flow of fluid in the event of stoppage of pump