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 : 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 : 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 mechanism used in Jaw crushers is (A) Attrition (B) Compression
Last Answer : (B) Compression
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 : 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
Last Answer : (A) Have greater capacity per unit of discharge area
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 : Size reduction of the __________ can be suitably done by ball mills, crushing rolls and rod mills. (A) Metalliferous ores (B) Non-metallic ores (C) Basic slags (D) Asbestos & mica
Last Answer : (A) Metalliferous ores
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 : A coal with high ash content is undesirable, as (A) It is abrasive to the coal pulveriser (i.e. ball mill) and the combustion chamber (B) The ash in molten condition gets absorbed in the pores of the ... and stick to the boiler tubes thereby reducing the heat transfer (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Ball mills and tube mills with flint or porcelain balls are used for size reduction of (A) Asbestos (B) Rubber (C) Non-metallic ores (D) Limestone
Last Answer : (C) Non-metallic ores
Description : __________ mills fall in the category of tumbling mills, (A) Ball and pebble (B) Rod and tube (C) Compartment (D) All (A), (B) & (C
Last Answer : (D) All (A), (B) & (C
Description : Balls for ball mills are never made of (A) Forged/cast steel (B) Lead (C) Cast iron (D) Alloy steel
Last Answer : (B) Lead
Description : _________ baffles are provided in ball mills. (A) Horizontal (B) No (C) Only two (D) None of these
Last Answer : (A) Horizontal
Description : Actual operating speed of a ball mill may vary from 65 to 80% of the critical speed. Which of the following duties would require the ball mill to be operated at maximum percentage of critical speed? (A) ... of large particles (upto 1.25 cms) (D) Dry grinding of large particles in un-baffed mills
Last Answer : (D) Dry grinding of large particles in un-baffed mills
Description : For efficient grinding, ball mills must be operated (A) At a speed less than the critical speed (B) At a speed more than the critical speed (C) At a speed equal to the critical speed (D) With minimum possible small balls
Last Answer : (A) At a speed less than the critical speed
Description : Pick out the correct statement. (A) Noise from ball mills can be dealt with by fibre glass lined enclosures (B) Noise from vibrating chutes can be reduced by lining the metallic chute with rubber (C) Noise ... cloth conveyor belts and rubber/plastic covered metallic rollers (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : Run of mine (ROM) coal is crushed by a __________ for use in domestic ovens. (A) Jaw crusher (B) Hammer crusher (C) Ball mill (D) Tube mil
Last Answer : (B) Hammer crusher
Description : Out of the following size reduction equipments, the maximum feed size can be accepted by the (A) Tube mill (B) Ball mill (C) Jaw crusher (D) Jet pulveriser
Last Answer : (C) Jaw crusher
Description : Arrange the following size reduction equipment in the decreasing order of the average particle size produced by each of them. (A) Jaw crusher, Ball mill, Fluid energy mill (B) Ball mill, Jaw crusher, Fluid ... C) Fluid energy mill, Jaw crusher, Ball mill (D) Fluid energy mill, Ball mill, Jaw crusher
Last Answer : (A) Jaw crusher, Ball mill, Fluid energy mill
Description : Feed size of ≥ 25 cms can be accepted by (A) Ball mill (B) Rod mill (C) Fluid energy mill (D) Jaw crusher
Last Answer : (D) Jaw 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 : Dephosphorization of molten pig iron is favoured by (A) Oxidising and basic slag (B) Reducing and basic slag (C) High activity co-efficient of phosphorous in metal (D) Oxidising and neutral slag
Last Answer : Option B
Description : Draw symbol of (i) Tray Dryer (ii) Plate column (iii) Packed column (iv) Jaw crusher (v) Strirrer (vi) Ball mill.
Last Answer : i)Tray dryer: ii)Plate column: iii)Packed column: iv) Jaw crusher: v) Stirrer: vi) Ball mill
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 : Size reduction of __________ is accomplished in steam heated rollers and roll crushers. (A) Resins (B) Gums (C) Hard rubber (D) Waxes
Last Answer : (C) Hard rubber
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 : 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 : Toothed roll crushers achieve size reduction by (A) Tearing (shear) and compression (B) Impact and attrition (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
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 : Which one of the following judgements stated that 'Secularism' and 'Federalism' are the basic features of the Indian ConstantLion? (1) Keshavananda Bharati case (2) S.R. Bommai case (3) Indira Sawhney case (4) Minerva Mills case
Last Answer : (2) S.R. Bommai case Explanation: In the S.R. Bommai Case v. Union of India (1994), Justice Sawant and Kuldip Singh observed that federalism and secularism was an essential feature of our ... In this case, the Supreme Court discussed at length provisions of Article 356 of the Constitution of India.
Description : The Basic Structure of our Constitution was proclaimed by the Supreme Court in – (1) Keshvananda Bharati Case (2) Golak Nath Case (3) Minerva Mills Case (4) Gopalan Case
Last Answer : (1) Keshvananda Bharati Case Explanation: The basic structure doctrine was first articulated by Justice Hans Raj Khanna in the landmark decision of Kesavananda Bharati v. State of Kerala (case ... the power to destroy or emasculate the basic elements or fundamental features of the constitution.
Description : Which of the following is the most widely used insulating material for steam carrying pipelines? (A) Ceramic fibre blanket (B) Glass wool and 85% magnesia (C) Vermiculite (D) Slag wool
Last Answer : (B) Glass wool and 85% magnesia
Description : High ash containing coke (A) Produces more slag when used in the blast furnace (B) Has poor strength and abrasion resistance (C) Is desirable in producer gas manufacture (D) None of these
Last Answer : (A) Produces more slag when used in the blast furnace
Description : Low grade phosphate rock can be used in electrical furnace, because (A) Of the better CaO/SiO2 balance for slag formation (B) CaO content is less (C) It is cheap (D) It produces low cost product
Last Answer : (A) Of the better CaO/SiO2 balance for slag formation
Description : Raw materials used for producing __________ cement does not contain iron oxide. (A) Waterproof (B) Slag (C) White (D) Pozzolan
Last Answer : (C) White
Description : Ceramics are produced from silicates or clayish materials: Which of the following is not a ceramic material? (A) Slag cement (B) Glasses (C) Porcelain/Potteries (D) Teflon
Last Answer : (D) Teflon
Description : Pick out the wrong statement. (A) Dry process is used for the manufacture of cement, when the raw material is blast furnace slag (B) Portland cement is made employing wet process (C) Gypsum is added to Portland cement to lengthen its setting time (D) None of these
Last Answer : (D) None of these
Description : Flux addition during smelting of ore is done to (A) Remove impurities/gangue (B) Enhance rate of reaction (C) Accelerate reduction of ore (D) Separate slag from metal
Last Answer : (A) Remove impurities/gangue
Description : Specific gravity of hot metal (pig iron) is __________ times that of the blast furnace slag. (A) 2 (B) 3 (C) 0.8 (D) 6
Last Answer : (B) 3
Description : Most of the phosphorous present in the blast furnace burden enters into (A) Hot metal (B) Flue gases (C) Slag (D) Refractory lining
Last Answer : (A) Hot metal
Description : Which of the following is an undesirable property of slag produced during the Pyrometallurgical method of metal extraction from its ore? (A) High fusibility & fluidity (B) High thermal conductivity (C) Low density (D) High chemical activity
Last Answer : B) High thermal conductivity
Description : furnace slag is mainly molten (A) Sand (B) Magnesium silicate (C) Calcium silicate (D) Iron pyrite
Last Answer : Option C
Description : Wrought iron is not (A) Ductile & resistant to corrosion/rusting (B) Weldable easily (C) Having uniform strength in all directions (D) Having maximum tensile strength along the lines of slag distribution
Description : Limestone is added in the blast furnace (during pig iron manufacture) to (A) Form slag by combining with impurities (B) Supply heat by undergoing exothermic reaction with impurities (C) Reduce the coke consumption (D) Reduce slag viscosity
Last Answer : Option A
Description : Which of the following is an acidic constituent of B.F. slag? (A) SiO2 (B) FeO (C) MgO (D) CaO
Description : The function of neutral flux used in the pyrometallurgy of metal extraction is to increase the __________ of the slag. (A) Fluidity (B) Basicity (C) Acidity (D) Viscosity
Description : 9. Which of the following is an acidic constituent of B.F. slag? (A) SiO2 (B) FeO (C) MgO