Gyratory crushers compared to the reciprocating jaw crushers
(A) Have greater capacity per unit of discharge area
(B) Crush intermittently
(C) Are less suitable for coarse materials
(D) Have less steady power consumption

1 Answer

Answer :

(A) Have greater capacity per unit of discharge area

Related questions

Description : As per Taggart's formula, the capacity (kg/hr) of Jaw & Gyratory crushers (for gapes of 10 to 60 cms) is equal to (where, L = Length of feed opening, cms S = Maximum width of discharge opening, cms). (A) LS (B) 93 LS (C) 250 LS (D) √(LS)

Last Answer : (B) 93 LS

Description : Reciprocating screens are normally inclined at an angle of 5° with the horizontal and employ gyratory motion at feed end & reciprocating motion at the discharge end. They are not suitable for the ... Dry chemicals (C) Heavy tonnages of rocks or gravel (D) Powdered food & granular materials

Last Answer : (C) Heavy tonnages of rocks or gravel

Description : Capacity (in tons/hr) of jaw/gyratory crusher is equal to (where, L = length of the receiving opening, cm S = greater width of the discharge opening, cm). (A) 0.01 L.S (B) 0.087 L.S (C) L.S (D) L.S/0.087

Last Answer : (B) 0.087 L.S

Description : The term 'angle of nip' is concerned with the operation of the __________ crushers. (A) Jaw (B) Roll (C) Gyratory (D) None of these

Last Answer : (B) Roll

Description : Size reduction does not occur due to compression in case of (A) Rod mills (B) Gyratory crushers (C) Jaw crushers (D) Smooth roll crushers

Last Answer : (A) Rod mills

Description : Which of the following crushers can be considered as a combination of a jaw crusher and a roller crusher? (A) Rod mill (B) Fluid energy mill (C) Gyratory crusher (D) Ball mill

Last Answer : (C) Gyratory crusher

Description : Pick out the wrong statement. (A) For the compressible cake, voidage & the specific resistance of the cake can be assumed to be constant (B) Cake resistance is independent of the pressure ... Crushing of explosive materials are done by employing dry-grinding (D) Gyratory crusher is a coarse crusher

Last Answer : (B) Cake resistance is independent of the pressure drop

Description : The capacity of a gyratory crusher is __________ that of a jaw crusher with the same gape, handling the same feed & for the same product size range. (A) Same as (B) 2.5 times (C) 5 times (D) 10 times

Last Answer : (B) 2.5 times

Description : Size reduction of asbestos and mica is done by (A) Hammer mills (B) Rod mills (C) Gyratory crushers (D) Crushing rolls

Last Answer : (A) Hammer mills

Description : Pick out the wrong statement pertaining to the roll crushers. (A) Maximum feed size determines the required roll diameter (B) For hard material's crushing, the reduction ratio should not ... ratio and differential roll speed affect production rate & energy consumed per unit of surface produced

Last Answer : (C) Both the rolls run necessarily at the same speed

Description : According to Taggart's rule for selecting between a gyratory crusher and a jaw crusher; the later should be used, if the hourly tonnage to be crushed divided by the square of the gape expressed in cm is less than (A) 0.00184 (B) 0.0184 (C) 0.184 (D) 1.84

Last Answer : (B) 0.0184

Description : Choke crushing (in case of a Jaw crusher) compared to free crushing (A) Results in increased capacity (B) Consumes less power (C) Consumes more power (D) Both (A) and (C)

Last Answer : (C) Consumes more power

Description : Size reduction mechanism used in Jaw crushers is (A) Attrition (B) Compression

Last Answer : (B) Compression

Description : Basic slag is not ground in (A) Jaw crushers (B) Ball mills

Last Answer : (A) Jaw crushers

Description : Pick out the wrong statement. (A) More commonly used jaw crusher between Dodge jaw crusher and Blake jaw crusher is the later one (B) There are only four methods namely compression, impact ... Operating principles of Dodge and Blake jaw crushers are combined in the working of universal jaw crushers

Last Answer : (C) Cutting machines mainly employ 'attrition' for size reduction of solids

Description : Which of the following is a coarse crusher? (A) Smooth roll crusher (B) Toothed roll crusher (C) Gyratory crusher (D) Tube mill

Last Answer : (C) Gyratory crusher

Description : Pick out the wrong statement: (A) Magnetic separation method can be employed to treat both dry & wet ores (B) Reduction ratio in crushing operation is defined as the ratio of minimum feed ... ) Gyratory crusher is used for coarse crushing (D) Screens are of stationary, moving and vibratory types

Last Answer : (B) Reduction ratio in crushing operation is defined as the ratio of minimum feed size to the maximum product size

Description : Which of the following comes in the category of primary crusher for hard and tough stone? (A) Jaw crusher (B) Cone crusher (C) Gyratory crusher (D) None of these

Last Answer : (A) Jaw crusher

Description : Which of the following is a fine crusher? (A) Blake jaw crusher (B) Gyratory crusher (C) Toothed roll crusher (D) Dodge jaw crusher

Last Answer : (C) Toothed roll crusher

Description : Size reduction of ice and gypsum can be accomplished suitably by a __________ crusher. (A) Blake jaw (B) Toothed roll (C) Gyratory (D) None of these

Last Answer : (B) Toothed roll

Description : Which of the following achieves the least reduction ratio for a given feed size? (A) Jaw crusher (B) Roll crusher (C) Cone crusher (D) Gyratory crusher

Last Answer : (B) Roll crusher

Description : To get a fine talc powder from its granules, the equipment used is (A) Roller crusher (B) Ball mill (C) Jaw crusher (D) Gyratory crusher

Last Answer : (B) Ball mill

Description : A double acting reciprocating pump compared to a single acting pump (of almost same size working under same pressure levels) would give almost double (A) Head (B) Discharge (C) Efficiency (D) None of these

Last Answer : (B) Discharge

Description : Centrifugal pumps as compared to reciprocating pumps (A) Run at a lower speed for the same discharge (B) Do not need priming (C) Deliver fluid with pulsating/fluctuating discharge (D) Can be run with discharge line valve closed for a short interval

Last Answer : (D) Can be run with discharge line valve closed for a short interval

Description : Diaphragm electrolytic cell as compared to mercury electrolytic cell (A) Produces 70% NaOH solution (B) Requires less specific power consumption for the production of chlorine (C) Requires lesser investment for similar capacity (D) All (A), (B) and (C)

Last Answer : (C) Requires lesser investment for similar capacity

Description : Reduction ratio of crushers is the (A) Ratio of feed opening to discharge opening (B) Ratio of discharge opening to feed opening (C) Determining factor for minimum dia of the feed and the product (D) None of these

Last Answer : (A) Ratio of feed opening to discharge opening

Description : From base load operation and from achieving best specific energy consumption point of view, which of the following compressors are suitable? a) Single stage reciprocating compressors b) Centrifugal compressors c) Two stage reciprocating compressor d) Multi stage reciprocating compressor

Last Answer : b) Centrifugal compressors

Description : From the point of lower specific energy consumption, which of the following compressors are suitable for part load operation? a) Two stage reciprocating compressors b) Centrifugal compressors c) Two stage screw compressor d) Single stage screw compressor

Last Answer : a) Two stage reciprocating compressors

Description : Which of the following parts of a jaw crusher is subjected to maximumwear and tear during its operation? (A) Check plates (B) Jaw plates (C) Toggles (D) Crush shaft

Last Answer : (B) Jaw plates

Description : Bond crushing law (A) Calls for relatively less energy for the smaller product particles, than does the Rittinger law (B) Is less realistic in estimating the power requirements of commercial crushers ( ... (D) States that the work required for the crushing is proportional to the new surface created

Last Answer : (A) Calls for relatively less energy for the smaller product particles, than does the Rittinger law

Description : Centrifugal compressors compared to reciprocating compressors (A) Require less space (B) Have quieter operation (C) Have lower operating costs (D) All (A), (B) and (C)

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

Description : Which of the following is used for primary crushing of very hard lumpy materials? (A) Toothed roll crusher (B) Gyratory crusher

Last Answer : (B) Gyratory crusher

Description : The static load carrying capacity of fine threads is greater than that of coarse threads. a) True b) False

Last Answer : b) False

Description : For a reciprocating pump, the indicator diagram is the graph between the (A) Discharge and overall efficiency (B) Volume swept by piston for one complete revolution and the pressure in the cylinder (C) Angle swept by the crank pin at any instant and the discharge (D) None of these

Last Answer : (B) Volume swept by piston for one complete revolution and the pressure in the cylinder

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

Description : For very low pressure and high discharge rate, the compressor used is a/an __________ compressor. (A) Axial (B) Reciprocating (C) Rotary (D) None of these

Last Answer : (C) Rotary

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

Description : Which of the following is most prone to pulsating discharge flow? (A) Centrifugal pump (B) Reciprocating pump (C) Gear pump (D) Axial flow pump

Last Answer : (C) Gear pump

Description : Function of air vessel provided in a reciprocating pump is to (A) Reduce discharge fluctuation (B) Reduce the danger of cavitation (C) Avoid the necessity of priming (D) Increase the pump efficiency

Last Answer : (A) Reduce discharge fluctuation

Description : Air vessel fitted to a reciprocating pump (A) Increases the work done (B) Decreases the work done (C) Causes cavitation (D) Results in non-uniform discharge

Last Answer : (B) Decreases the work done

Description : Purpose of relief valve in a reciprocating pump is to (A) Protect the pump against developing excessive pressure (B) Facilitate unidirectional flow of liquid (C) Reduce the discharge pressure (D) Control the rate of discharge

Last Answer : (A) Protect the pump against developing excessive pressure

Description : In case of unsteady fluid flow, conditions & flow pattern change with the passage of time at a position in a flow situation. Which of the following is an example of unsteady flow? (A) ... level is maintained (D) Low velocity flow of a highly viscous liquid through a hydraulically smooth pipe

Last Answer : (B) Water flow in the suction and discharge pipe of a reciprocating pump

Description : Pick out the wrong statement. (A) Hammer crushers operate by impact action (B) Standard screens have circular opening (C) With increase in mesh number of screens, their diameter in microns decreases (D) 200 mesh screen has 200 openings per linear cm

Last Answer : (D) 200 mesh screen has 200 openings per linear cm

Description : Select the wrong statement pertaining to flow of an incompressible fluid through a Venturimeter. (A) For frictionless flow, the fluid pressure entering the venturi meter will be exactly equal ... than an orificemeter (D) Venturimeter incurs less power loss compared to an equivalent orificemeter

Last Answer : (C) Venturimeter occupies less space than an orificemeter

Description : Pick out the wrong statement. (A) Longer tubes are less expensive per unit heat transfer area as compared to shorter tubes (B) A cost index is merely a number for a given year ... butt welded joints are less expensive compared to lap welded joints, because squaring of plates is not necessary

Last Answer : (D) Plates with butt welded joints are less expensive compared to lap welded joints, because squaring of plates is not necessary

Description : Rotary drilling (A) Is not suitable for deposits containing very coarse gravel (B) Hinders the ground water observations and permeability test (C) Is not economical for holes of less than 10 cm (D) All the above

Last Answer : Answer: Option D

Description : Most important method for calculating discharge for planning a water supply project, is  (A) Velocity area method  (B) Weir or spillway method  (C) Use of venturi-meter  (D) Using power plant consumption 

Last Answer : (A) Velocity area method

Description : Energy requirement (per unit mass of material crushed/ground) is highest for (A) Jaw crusher (B) Rod mill (C) Ball mill (D) Fluid energy mil

Last Answer : (D) Fluid energy mil

Description : Consider the following statements: Air vessels are fitted on the suction and delivery sides of a reciprocating pump to 1. Achieve higher speed without separation. 2. Reduce work in overcoming frictional resistance. 3. Avoid excessive vibration ... 2 & 3 only (c) 2, 3 & 4 only (d) 1, 2, 3 & 4

Last Answer : (d) 1, 2, 3 & 4

Description : List the advantages of keeping the discharge pressure for reciprocating compressors at minimum. 

Last Answer : Lower power consumption Less load on the piston rods and hence reduced maintenance costs Lower leakage losses