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Here you will find a list of some top technical interview questions that are most often asked by tech employers and recruiters.
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Prepared By: ENG. AHMED OSSAMA
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1 MECHANICAL ENGINEERING
Pumps & Hydraulics Q1: Pumps classification.
Q2: What are the types of pump impeller?
Q3: Draw the Characteristic curves of different type of pumps.
Q4: Theory of operation of different type of pumps.
Q5: Methods of pump priming.
Q6: Methods of elimination pumps' thrust force.
Q7: What is meant by Cavitations, 𝑁𝑃𝑆𝐻𝑅 , 𝑁𝑃𝑆𝐻𝐴?
Q8: Identify the best efficient point (bep).
Q9: Preferred range of operation of centrifugal pump.
Q10: What happens if the operation point of CP >> or << from bep?
Q11: Explain briefly, Mechanical sealing and Wearing ring.
Q12: define piping and fittings.
Q13: Draw a Multi-Stage pump.
Q14: Label the centrifugal pump schematic diagram.
Q15: Flow rate preferred at starting of CP and Propeller pump.
Q16: label the components of the next hydraulic circuit and explain the
system briefly.
Q17: Pump produces flow rate or pressure?
Q18: A pump used to transfer water from one tank to another, where
the level difference between the two tanks is 20m and the pipe is 150m
long and 4inch diameter and (f = 0.02) and the velocity of flow through
the pipe is 2 m/s, assuming that total head loss coefficient of the system
(k) = 2.5 and pump efficiency is 80%. Find pump’s shaft power in KW.
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2 MECHANICAL ENGINEERING
Q19: How to differentiate between the suction and delivery lines of a
CP pump?
Q20: What is the most used engineering equipment after electric motor?
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3 MECHANICAL ENGINEERING
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4 MECHANICAL ENGINEERING
Compressors
Q21: Compressors classification.
Q22: Why we use inter-cooling between compressors stages?
Q23: Explain surge and choke phenomena.
Q24: Differentiate between pumps and compressors.
Q25: Draw characteristic curve of different types of compressor.
Q26: Name and Label next compressor schematic diagram.
Q27: Draw P-V diagram of reciprocating compressor.
Q28: Types of screw compressor.
Q29: Method of controlling surge.
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Thermodynamics Q30: Steam turbine classification.
Q31: Turbine classification.
Q32: Why we use reheat in multi-stage steam turbine?
Q33: How to decrease condenser pressure?
Q34: What will open first S/H safety valve or Evaporator safety valve?
Q35: What is the Turbine work?
Q36: Name and explain the boiler components.
Q37: What are the difference between fire tube and water tube?
Q38: How to differentiate between gas turbine's blade and compressor
blade?
Q39: Mention the four processes in the simple Rankin cycle on T – S
diagram and also draw a physical layout of the four devices use in the
cycle.
Q40: Mention the four processes in the ideal Brayton cycle on T – S
diagram and also draw a physical layout of the four devices use in the
cycle.
Q41: Identify the dew point temperature.
Q42: If two bodes one was cold and the other was hot in what direction
the heat transfers will occurs from cold to hot or from hot to cold.
Q43: What are the types of gas turbine combustors?
Q44: What are the three laws of thermodynamics?
Q45: Mention some of the Renewable alternative source of energy.
Q46: What are the modes of heat transfer?
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Q47: What are the types of boilers?
Q48: Mention the main components of any refrigeration system and also
draw the P-H diagram of refrigeration cycle and a physical layout of the
four devices used in the cycle
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Automotive & Engines Q49: Compare between Diesel and gasoline engines.
Q50: Explain the following,
1. Detonation
2. Diesel knock
3. Octane number
4. Cetane number
5. Compression ratio
6. Pour point
7. Flash point
Q51: What are the main components of any automobile engine?
Q52: Explain the 4 and 2 stroke engine with drawing.
Q53: Mention the four processes in the ideal Brayton cycle on T – S
diagram and also draw a physical layout of the four devices use in the
cycle.
Q54: Draw P-V diagram for an ideal Otto (gasoline) 4-stroke cycle and
P-V diagram for the actual combustion Otto cycle.
Q55: Why it is preferred to use Diesel engines in huge trucks and
loaders and to use Gasoline engines in small personal cars.
Q56: Why using leaf spring in the rear wheels of large trucks instead of
helical springs?
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Mechanical Design Bearings Q57: What are the types of bearing?
Q58: Differentiate between hydro-static and hydro-dynamic bearing.
Q59: What type of bearing used in high speed machines?
Q60: Lubrication oil used in turbo-machinery heavy or light and why?
Gears
Q61: What are the types of gears?
Q62: Explain the following, Backlash, Circular pitch, Gear module
Q63: When we use spur gears and when we use helical gears?
Standards
Q64: What are the following abbreviations referred to?
1. ISO
2. OSHA
3. ASME
4. API
5. ASTM
6. ANSI
7. SI
Q65: Mention some of international standards and codes.
Q66: Differentiate between international standers and national
standards.
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Gauges and Sensors
Q67: Mention three devices to measure temperature and explain one of
them.
Q68: Mention three devices to measure Pressure and explain one of
them.
Q69: Mention three sensors and explain.
Q70: Why we use inclined manometer instead of U-tube manometer in
low pressure measurements.
Welding
Q71: Types of welding.
Q72: Mention with draw the welding joints.
Q73: Types of welding electrodes.
Q74: welding symbols.
Materials
Q75: Types of materials.
Q76: Explain the following,
1. Yield strength
2. Torsion strength
3. Tension strength
4. Compression strength
Q77: Mention with drawing different type of steel structures.
Q78: What is the different between Elasticity scientific subject and
Mechanics of Materials scientific subject?
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MECHANICAL ENGINEERING
Q79: Differentiate between Elastic and plastic Deformation.
Q80: Define Necking Region.
Q81: Differentiate between destructive and nondestructive testing of the
materials.
Q82: Mention some of NDT (Nondestructive Testing) techniques and
applications.
Q83: Why the material of the sleeves that hold and surround the
crankshaft are made from soft materials.
Q84: Why most of the shafts are made from rigid materials.
Vibration
Q85: Mention some of the devices that used to measure the vibration of
mechanical systems.
Q86: Explain briefly the following statements,
1. Resonance phenomena
2. 1st critical speed
3. 2nd critical speed
4. Natural frequency
5. System frequency
Q87: In order to detect the accurate vibration measurements in high
speed machines we measure displacement or velocity or acceleration of
the system.
Q88: In order to detect the accurate vibration measurements in medium
speed machines we measure displacement or velocity or acceleration of
the system.
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Q89: In order to detect the accurate vibration measurements in low
speed machines we measure displacement or velocity or acceleration of
the system.
Q90: How did the failure of the famous Tacoma narrows bridge
happened? Reasoned, relying on principles of mechanical vibration.
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MECHANICAL ENGINEERING
Maintenance &
Troubleshooting Q91: What is the world ranking for the main reasons of mechanical
defects?
Q92: Mention types of maintenance and the philosophy of each one of
them and explain.
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Fire Fighting Q93: Explain the fire triangle.
Q94: What are the classes of fire?
Q95: What is the extinguishing agent for each class?
Q96: What are the pumps use in the fire fighting systems and there
arrangements?
Q97: What is the function of jokey pump?
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MECHANICAL ENGINEERING
Electric Power Q98: What does Ohm's Law state, and mention its formula?
Q99: What are the types of electric motors?
Q100: What is the different between isolator and circuit breaker?
Q101: What is the different between electric motor and a generator?
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Table of Contents
Title .................................................................................................. Pages
Pumps & Hydraulics ............................................................................. 1,2,3
Compressors .............................................................................................. 4
Thermodynamics .................................................................................... 5,6
Automotive & Engines ............................................................................... 7
Mechanical Design ........................................................................ 8,9,10,11
Maintenance &Troubleshooting ............................................................. 12
Fire Fighting ............................................................................................. 13
Electric Power .......................................................................................... 14
Wish U All the Best – Success & Happiness
