Description : Differentiate between : (i) Reciprocating and rotary air compressor (ii) Centrifugal and axial flow compressor
Last Answer : (i) Reciprocating and rotary air compressor: Sr. No. Reciprocating air compressor Rotary air compressor 1 It is having to and fro motion. It is having rotary ... I.C. engine and for refrigerants and industrial gases. Used universally with large gas turbine.
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 can be used to create a flow of gas, where no significant compression is required? (A) Reciprocating compressor (B) Blower (C) Axial flow compressor (D) Centrifugal compressor
Last Answer : (B) Blower
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
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 : The domestic refrigerator uses following type of compressor (a) centrifugal (b) axial (c) miniature sealed unit (d) piston type reciprocating
Last Answer : Ans: d
Description : Which one of the following types of compressor is mostly used for supercharging of IC engines? (a) Radial flow compressor (b) Axial flow compressor (c) Root blower (d) Reciprocating compressor
Last Answer : Ans : c
Description : Compressor mostly used for supercharging of IC engine is A. Radial flow compressor B. Axial flow compressor C. Root blower compressor D. Reciprocating compressor
Last Answer : ANSWER : A
Description : Which one of the following type of compressor is mostly used for supercharging of I.C engine A. Radial flow compressor B. Axial flow compressor C. Root blower D. Reciprocating compressor.
Last Answer : ANSWER : C
Description : The specific speed of a centrifugal compressor is generally A. less than that of reciprocating compressor B. independent of compressor type, but depends only on size of compressor C. higher ... axial compressor D. more than specific speed of reciprocating compressor but less than axial compressor
Description : What Is The Difference Between A Rotary Screw Compressor And A Reciprocating Compressors?
Last Answer : A rotary screw compressor is one that utilizes two intermeshing helical rotors to trap a volume of air, then compress it to a higher pressure. Rotary screw compressors can be run at lower ... piston compressor (aka reciprocating) uses pistons driven by a crankshaft to deliver air at high pressure.
Description : Compare reciprocating and rotary air compressor
Last Answer : Reciprocating compressor Rotary compressor 1. Compression of air takes place with help of piston and cylinder arrangement with reciprocating motion of piston. 1. Compression of air takes place ... High 12. More Starting torque required 12. Less Starting torque required
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 : The maximum delivery pressure of a reciprocating compressor may be about __________ kg/cm2 . (A) 1000 (B) 2000 (C) 3000 (D) 4000
Last Answer : (D) 4000
Description : Horsepower increase of a centrifugal gas compressor without altering the volumetric flow rate will __________ the gas discharge pressure. (A) Increase (B) Decrease (C) Not change (D) Exponentially decrease
Last Answer : (A) Increase
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 : A large clearance volume in a reciprocating compressor results in A. Reduced volume flow rate B. Increased volume flow rate C. Lower suction pressure D. Lower delivery pressure
Description : A large clearance volume in reciprocating compressor results in A. reduced volume flow rate B. Increased volume flow rate C. Lower suction pressure D. Lower delivery pressure
Description : A reciprocating compressor is not suitable for use as a supercharger because: A. it runs at lower rpm B. the pressure ratio is high C. volumetric efficiency is high D. it is bulky and can handle small quantity of air
Last Answer : ANSWER : D
Description : A compressor that takes suction at a pressure below atmospheric and discharge against atmospheric pressure is called a __________ pump. (A) Sump (B) Volute (C) Vacuum (D) Submerged
Last Answer : (C) Vacuum
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 : 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 : 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 : In a two stage reciprocating air compressor with a suction pressure of 2 bar and delivery pressure of 8 bar the ideal intercooler pressure will be A. 10 bar B. 6 bar C. 4 bar D. 3 bar
Description : In a single stage reciprocating air compressor, the work done on air to compressor is from suction pressure to delivery pressure will be minimum when the compression is A. Isothermal process B. Adiabatic process C. Polytropic process D. Constant pressure process.
Description : Which one of the following statement is not correct for the volumetric efficiency of a reciprocating air compressor? A. It decreases with increase in ambient temperature B. It increases with ... It increases with decrease in clearance ratio D. It decreases with increases in delivery pressure
Description : In a two stage reciprocating air compressor, the suction and delivery pressure are 1 and 4 bar respectively. For maximum efficiency the intercooler pressure is A. 1.5 bar B. 2 bar C. 2.5 bar D. 3 bar
Last Answer : ANSWER : B
Description : Which one of the following statements are correct for reciprocating air compressor? A. Its volumetric efficiency increases with increasing clearance ratio B. Its volumetric efficiency increases ... ratio D. Its volumetric efficiency decreases with increasing clearance ratio and pressure ratio
Description : The compressor capacity of a reciprocating compressor is directly proportional to __ a) Speed b) Pressure c) Volume d) All
Last Answer : a) Speed
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
Description : Why the work per kg of air flow in axial flow compressor is less compared to centrifugal compressor for same pressure ratio ?
Last Answer : Isentropic efficiency of axial flow compressor is higher.
Description : The maximum delivery pressure in a rotary air compressor is A. 10 bar B. 20 bar C. 30 bar D. 50 bar
Description : Often an unbalance of forces is produced in rotary or reciprocating machinery due to the ______ * 1 point (A) Centripetal forces (B) Centrifugal forces (C) Friction forces (D) Inertia forces
Last Answer : (D) Inertia forces
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 : 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 : 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 : 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 : In a single acting reciprocating compressor, the suction, compression and delivery of air takes place in A. One stroke B. Two stroke C. Three stroke D. Four stroke
Description : In reciprocating air compressor the clearance ratio is given by A. B. C. D.
Description : Reciprocating compressor are provided with A. Simple disc/plate valve B. Poppet valve C. Spring-loaded disc valve D. Solenoid valve.
Description : In a reciprocating air compressor the compressor work per kg of air A. Increases as clearance volume increases B. Decreases as clearance volume increases C. Is independent of clearance volume D. Increases with clearance volume only of multistage compressor
Description : Under what condition the work done in reciprocating compressor will be least ?
Last Answer : It is least when compression process approaches isothermal. For this purpose, attempts are made to cool the air during compression.
Description : What points to be considered for reciprocating compressor piping layout?
Last Answer : Answer: High pulsation, simple line as low to grade as possible for supporting, analog study, all branches close to line support and on top, Isolate line support from adjacent compressor or building foundations
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 : Explain the factors affecting volumetric efficiency of reciprocating air compressor.
Last Answer : Factors affecting volumetric efficiency of reciprocating air compressor: 1) Clearance Volume 2) Restricted passage and leakage at inlet valves 3) Speed of rotation 4) Piston ring leakages ... wall, it get expanded, which decreases the charge taken in therefore volumetric efficiency decreases.
Description : Two stage reciprocating air compressor with P – V diagram
Last Answer : Two stage reciprocating air compressors consist of two cylinders. One is called low-pressure cylinder and another is called high-pressure cylinder. When piston in a low-pressure cylinder is at ... & discharge valves open. This desired high-pressure air is then delivered to a receiver.
Description : Rotary vacuum pumps can reduce the absolute pressure to as low as __________ mm Hg. (A) 1 (B) 0.1 (C) 0.01 (D) 0.001
Last Answer : (C) 0.01
Description : Paddle agitator (A) Is suitable for mixing low viscosity liquids (B) Produces axial flow (C) Moves at very high speed (D) None of these
Last Answer : (A) Is suitable for mixing low viscosity liquids