Aug 19, Click Here> "MECHANICAL ENGINEERING Multiple Choice Questions" ENGINEERING Interview Questions and Answers PDF. Dec 9, 25 best mechanical engineering interview questions and answers pdf free download. 1. Mechanical Engineering Interview questions and. Mechanical Engineering Interview Questions and Answers - Download as PDF File .pdf), Text File .txt) or read online.

Interview Questions For Mechanical Engineering Pdf

Language:English, Indonesian, Portuguese
Published (Last):27.07.2016
ePub File Size:21.76 MB
PDF File Size:8.82 MB
Distribution:Free* [*Registration needed]
Uploaded by: LARA

Feb 27, Look at the following links for questions that are generally asked for the position of mechanical engineering? 1. Top + Mechanical Engineering Interview. + Mechanical Engineering Interview Questions and Answers, Question1: What is extrued aluminum? Question2: What is the mechanical advantage of a. Mechanical Engineering Interview Questions and Answers All students, freshers can download Mechanical Engineering quiz questions with answers as PDF.

The only way to gain this mastery is to work in similar environments until the skill becomes a habit. The tragedy is that most of them can write the answer on a Interview calls are difficult to come by.

This single shortcoming ruins the lives of millions of value. Therefore Interview Simulator. It reveals your mistakes well-qualified people, even forcing many to drugs and suicides.

It has over carefully selected interview questions in video format from 49 topics of Mechanical Engineering. You can attempt any number of new interviews. Part 2: Interview Trainer in 3 Modules - 1. Mechanical Engineering Competency Tests.

For example, Do you understand the hidden meanings of the questions as it is being asked? Are you able to formulate an answer within 5 to 6 seconds?

Are you speaking in full sentences with clarity? Are you using the right technical terminologies like a professional? Is your response the right answer? Are you responding crisply? How are your facial expressions and gestures? The step-by-step method for the Professional Interview Simulation: 1. Create Your Personal Profile: Interviews are created based on your educational qualifications; Experience or,Fresher , Area of specialisation, Type of the target company for employment etc.

Drop down menu as in the table below. Your responses are captured by the camera for various modes of evaluation. Five Options of Evaluations: 1.

Download Mechanical Engineering Interview Questions & Answers PDF:

Auto Report, 2. Self Review, 3. Peer Review, 4. Mentor Evaluation, and 5. Espoir Expert Evaluation. For details refer to the FAQ.

Online demos are available for most of the above interview topics.

Visit www. The step-by-step method to use the Professional Interview Trainer: 1. Begin the practice session, and face the first question from the screen: You can re-play the question till you clearly understand the question. You can also read the question as an English subtitle.

Answer to the question on camera, play it, fine-tune it till you are satisfied: You can attempt infinite number of times to fine-tune your answer, body-language etc. Refer to best responses: You can refer to the best responses for each question. These answers contains the key points, words and phrases the interviewers look for.

What you should say and what you should not say, etc. These questions are handpicked by the experts in the field and can be used for many other competitive examinations besides technical interviews. Therefore, this section contains over questions, their hidden meanings, sample answers, words and phrases to use while answering etc. To know about all other features, please visit the website. The imperatives of Interview Preparation.

How do we use Simulation for Interview success. How to ensure success? Understanding the underlying meaning of those unexpected, tricky questions. STAR Method of answering questions. Column is always vertical but strut as member of structure could carry axial compressive load in any direction.

Explain the difference between ferrite, austenite and graphite? Ferrite is the solid solution of carbon and other constituents in alpha-iron. It is soft, ductile and relatively weak. Austenite is the solid solution of carbon and other constituents in gamma-iron.


It exists in ordinary steels at elevated temperatures, but it is also found at ordinary temperatures in some stainless steels. Graphite has a hexagonal layer lattice.

Explain the terms solid solution, eutectic, eutectoid and peritectic. What do you understand by critical points in iron, iron-carbide diagram? The temperatures at which the phase changes occur are called critical points or temperatures. PERT is based on the approach of multiple time estimates for each activity.

What is stellite? It is a non-ferrous cast alloy containing cobalt, chromium and tungsten. Which rays are produced by cobalt in industrial radiography? Gamma rays. What are killed steels and what for these are used? Killed steels are deoxidised in the ladle with silicon and aluminium.

On solidification no gas evolution occurs in these steels because they are free from oxygen. What is critical temperature in metals?

It is the temperature at which the phase change occurs in metals. What is the structure of pure iron and whether it is soft or hard? Ferrite and it is soft. Which elements increase the corrosion resistance of steel? Chromium and nickel. What causes hardness in steel? How heat treatment alters properties of steel? The shape and distribution of the carbides in the iron determines the hardness of the steel. Carbides can be dissolved in austenite is the basis of the heat treatment of steel. If steel is heated above the A critical temperature to dissolve all the carbides, and then cooled, suitable cooling through the cooling range will produce the desired size and distribution of carbides in the ferrite, imparting different properties.

Explain the formation of microstructures of pearlite, bainite and martensite in steel. If austenite containing about 0. This microstructure is called pearlite. At temperatures just belot the A1, the transformation from austenite. This phase has a tetragonal crystal structure and contains carbon in supersaturated solid solution.

How with alloying of steel it is possible to a achieve properties which can not be achieved with heat treatment? A prerequisite to the hardening of steels is that martensite should be formed on cooling, but this can only be achieved if the rate of cooling is great enough to suppress the formation of pearlite or bainite and in plain carbon steels this can be achieved by quenching relatively small specimens.

What is the difference between austenite stabilisers and ferrite stabilisers? What are the effects of carbon on the properties of steel. In general, an increase in carbon content produces higher ultimate strength and hardness but lowers ductility and toughness of steel alloys.

Carbon also increases air-hardening tendencies and weld hardness, especially in the presence of chromium. In low-alloy steel for high-temperature applications, the carbon content is usually restricted to a maximum of about 0.

To minimize intergranular corrosion caused by carbide precipitation, the carbon content of austenitic type alloys is limited in commercial specifications to a maximum of 0. An increase in carbon content lessens the thermal and electrical conductivities of steel and increases its hardness on quenching. What is the role of silicon as alloying element in steels?

Silicon contributes greatly to the production of sound steel because of its deoxidizing and degasifying properties. When added in amounts up to 2. Silicon in excess of 2.

Mechanical Engineering Interview Questions and Answers

Resistance to oxidation and surface stability of steel are increased by the addition of silicon. These desirable effects partially compensate for the tendency of silicon to lower the creep properties of steel.

Silicon increases the electrical resistivity of steel and decreases hysteresis losses.

Discuss the role of manganese in alloying steels. Manganese is an excellent deoxidizer and sulfur neutralizer, and improves the mechanical properties of steel, notably the ratio of yield strength to tensile strength at normal temperatures.

It improves rolling properties, hardenability, and resistance to wear. However manganese increases the crack sensitivity of weldments, particularly with steels of higher carbon content. Define buckling factor. It is the ratio of the equivalent length of column to the minimum radius of gyration.

What do you understand by catenary cable? A cable attached to the supports and carrying its own weight. What is coaxing?

It is the process of improving fatigue properties by first under-stressing and then increasing the stress in small increments. What is isotropic material? It is a material having same elastic constants in all directions. Explain difference between modulus of resilience and modulus of rigidity?

Modulus of resilience is the maximum strain energy stored in a material per unit volume and modulus of rigidity is the ratio of shearing stress to the shearing strain within the elastic limit.

What is the difference between basic hole and basic shaft? A basic hole is one whose lower deviation is zero and in case of basic shaft the upper deviation is zero.

What for pyranometer is used? It is used to measure the total hemispherical solar radiation. Describe transfer machines in brief. It is an automatic machine in which workpiece alongwith fixture is transferred from one station to other automatically and several operation on workpiece are performed at each station.

What is burnt-out point? It corresponds to maximum heat flux at which transition occurs from nucleate boiling to film boiling.

What do you understand by eutectic? It is mechanical mixture of two or more phases which solidify simultaneously from the liquid alloy. Explain the difference between grey iron and white iron. What is mottled iron?

The carbon in cast iron could exist at room temperature as either iron carbide, or as graphite which is the more stable form. The graphite in grey irons exists in the form of flakes which act as stress-raisers under tensile loading and consequently grey irons have relatively low tensile strength and ductility.

Still grey iron is extensively used in engineering. Grey iron is extensively used in engineering because of following characteristics. Under what condition a convergent divergent nozzle required? When pressure ratio is greater than critical pressure ratio. What is endurance limit and what is its value for steel? Endurance limit is the maximum level of fluctuating stress which can be tolerated indefinitely.

How the net work to drive a compressor and its volumetric efficiency behave with increase in clearance volume? Work remains unaltered and volumetric efficiency decreases. What do you understand by sulphur print? Sulphides, when attached with dilute acid, evolve hydrogen sulphide gas which stains bromide paper and therefore can be readily detected in ordinary steels and cast irons.

While sulphur is not always as harmful as is sometimes supposed, a sulphur print is a ready guide to the distribution of segregated impurities in general. What is the different between brass and bronze?

Brass is an alloy of copper with zinc; and bronze is alloy of copper with tin. What is the effect of addition of zinc in copper? By addition of zinc in copper, both tensile strength and elongation increases. What for admirality brass used? Aluminium is also added to brass to improve corrosion resistance. What is the maximum use of magnesium? Magnesium is used to alloy with aluminium and as an additive for making SG Spheroidal Graphite iron. What for zinc finds applications? Galvanizing consumes the largest proportion of zinc.

Zinc is resistant to corrosion but is attacked by acids and alkalies. Zinc alloy. Which factors influence the type of fracture in failure of a material? Seven factors influencing type of failure are:. What is the name given to ratio of actual cycle efficiency and ideal cycle efficiency. Efficiency ratio. List two effects of manganese in plain carbon steels. Manganese increases tensile strength and hardness. It decreases weldability. Name the strongest and weakest type of atomic bonds.

Metallic bond is strongest and molecular bond also known as Vander Waals bond is weakest. In which process internal energy remains constant? Isothermal process.

Related titles

What is temper embrittlement in alloy steels and what are its effects? Embrittlement attack is usually intergranular in metals, i. It imparts a tendency to fail under a static load after a given period of time in those alloy steels which are susceptible to embrittlement. What are whiskers? Whiskers are very small crystals which are virtually free from imperfections and dislocations.

What is Bauschinger effect?

According to Bauschinger, the limit of proportionality of material does not remain constant but varies according to the direction of stress under cyclic stresses. What is the difference between heat capacity and specific heat of a material? Explain the rule to find specific heat of aqueous solutions. For aqueous solutions of salts, the specific heat can be estimated by assuming the specific heat of the solution equal to that of the water alone.

What do you understand by latent heat? Give four examples of latent heats. For pure substances, the heat effects accompanying changes in state at constant pressure no temperature change being evident are known as latent heats.

Examples of latent heats are: Define the terms free energy and free enthalpy. What is their significance and importance? It is equal to the work during a constant-volume isothermal reversible nonflow process.

For reversible isothermal steady-flow processes or for reversible constant-pressure isothermal nonflow processes, change in free energy is equal to net work. What is polytropic process? Under what conditions it approaches isobaric, isothermal, and isometric process? In which reversible process no work is done? No work is done in isometric process. Out of constant pressure and constant volume lines on TS diagram which line has higher slope? And whether slope is constant or variable?

Constant volume line. Slope is variable. Whether entropy is intensive property or extensive property? Entropy is extensive property. In which process fluid expands but does no work? Throttling process. What is the difference between scavenging and supercharging? Scavenging is process of flushing out burnt gases from engine cylinder by introducing fresh air in the cylinder before exhaust stroke ends. Supercharging is the process of supplying higher mass of air by compressing the atmospheric air.

What are the names given to constant temperature, constant pressure, constant volume, constant internal energy, constant enthalpy, and constant entropy processes. Isothermal, isochroic, isobaric, free expression, throttling and adiabatic processes respectively.

In a Rankine cycle if maximum steam pressure is increased keeping steam temperature and condenser pressure same, what will happen to dryness fraction of steam after expansion? Why entropy change for a reversible adiabatic process is zero? Because there is no heat transfer in this process. What are two essential conditions of perfect gas? It satisfies equation of state and its specific heats are constant. Enthalpy and entropy are functions of one single parameter. Which is that?

Why rate of condensation is higher on a polished surface compared to rusty surface? Polished surface promotes drop wise condensation and does not wet the surface. How much resistance is offered to heat flow by drop wise condensation?

What is the relationship between COP of heating and cooling? When maximum discharge is obtained in nozzle?

Engineering Questions

At the critical pressure ratio. Under what condition the work done in reciprocating compressor will be least? It is least when compression process approaches isothermal. For this purpose, attempts are made to cool the air during compression. What is the difference between stalling and surging in rotary compressions?

Stalling is a local phenomenon and it occurs when How breaks away from the blades. Surging causes complete breakdown of flow and as such it affects the whole machine.

Why the electric motor of a fan with backward curved blades is never got overloaded under any condition? For higher flow, power consumption gets lower. Why the work per kg of air flow in axial flow compressor is less compared to centrifugal compressor for same pressure ratio? Isentropic efficiency of axial flow compressor is higher. What is the name given to portion of thermal energy to be necessarily rejected to environment? What is pitting? How it is caused? Non uniform corrosion over the entire metal surface, but occuring only in small pits is called pitting.

It is caused by lack of uniformity in metal. What is caustic embrittlement? It is the actual physical change in metal that makes it extremely brittle and filled with minute cracks. It occurs particularly in the seams of rivetted joints and around the rivet holes. Which impurities form hard scale and which impurities soft scale?

Sulphates and chlorides of lime and magnesium form hard scale, and carbonates of lime and magnesium form soft scale. What is the difference between hard water and soft water? Hard water contains excess of scale forming impurities and soft water contains very little or no scale forming substances.

Which two elements in feed water can cause corrosion of tubes and plates in boiler? Acid and oxygen in feed water lead to corrosion. What should be done to prevent a safety valve to stick to its seat? Safety valve should be blown off periodically so that no corrosion can take place on valve and valve seat. Why large boilers are water tube type? Water tube boilers raise steam fast because of large heat transfer area and positive water circulation.

Thus they respond faster to fluctuations in demand. Further single tube failure does not lead to catastrophy. What type of boiler does not need a steam drum? Super-critical pressure boiler. Why manholes in vessels are usually elliptical in shape? Elliptical shape has minimum area of opening and thus plate is weakened the least.

Further it is very convenient to insert and take out the cover plate from elliptical opening. Low water in boiler drum is unsafe because it may result in overheating of water tubes in furnace. Why it is unsafe to have high water condition in boiler drum? High drum level does not allow steam separation to be effective and some water can be carried over with steam which is not desirable for steam turbine. Why boiler is purged every time before starting firing of fuel?

Purging ensures that any unburnt fuel in furnace is removed, otherwise it may lead to explosion. What is the principle of mechanical refrigeration? A volatile liquid will boil under the proper conditions and in so doing will absorb heat from surrounding objects. Why high latent heat of vaporisation is desirable in a refrigerant? A high latent heat of vaporisation of refrigerant results in small amount of refrigerant and thus lesser circulation system of refrigerant for same tonnage.

What is the critical temperature of a refrigerant? Critical temperature is the maximum temperature of a refrigerantrat which it can be condensed into liquid and beyond this it remains gas irrespective of pressure applied.

High temperature in I. Why efficiency of gas turbines is lower compared to I. Further combustion temperature of I. What do you understand by timed cylinder lubrication? For effective lubrication, lub oil needs to be injected between two piston rings when piston is at bottom of stroke so that piston rides in oi during upward movement. This way lot of lub oil can be saved and used properly. HUCR is highest useful compression ratio at which the fuel can be used in a specific test engine, under specified operating conditions, without knocking.

In some engines glycerine is used in place of water for cooling of engine. Thus weight of coolant gets reduced and smaller riadiator can be used.

Why consumption of lubricating oil is more in two-stroke cycle petrol engine than four-stroke cycle petrol engine? In two-stroke engine lub oil is mixed with petrol and thus some lub oil is blown out through the exhaust valves by scavenging and charging air. There is no such wastage in four stroke petrol engine. As compression ratio increases, thermal n increases. How is thermal n affected by weak and rich mixture strength?

Thermal n is high for weak mixture and it decreases as mixture strength becomes rich. How engine design needs to be changed to burn lean mixture?

Engine to burn lean mixture uses high compression ratio and the highly turbulent movement of the charge is produced by the geometry of the combustion chamber. Horse power of I. To which countries these standards belong?

What is the use of flash chamber in a vapour compression refrigeration cycle to improve the COP of refrigeration cycle?

When liquid refrigerant as obtained from condenser is throttled, there are some vapours. These vapours if carried through the evaporator will not contribute to refrigerating effect.

Using a flash chamber at some intermediate pressure, the flash vapour at this pressure can be bled off and fed back to the compression process. The throttling process is then carried out in stages. Similarly compression process is also done in two separate compressor stages. Why pistons are usually dished at top? What is the function of thermostat in cooling system of an engine?

Thermostat ensures optimum cooling because excessive cooling decreases the overall efficiency. It allows cooling water to go to radiator beyond a predetermined temperature. What are the causes of failure of boiler tubes? Boiler tubes, usually are made from carbon steel and are subject to a high rates of heat transfer, b bending stresses due to uneven heating, especially at expanded or welded joints into headers or drums, c external erosion from burners and flue gas, d possible corrosion on the boiler side, and e occasional manufacturing defects.

Failure may occur due to following reasons: The resultant overheating leads to a failure by creep, characterised by the bulging of the tube with the eventual development of a longitudinal split. Lamination in boiler tubes or score marks arising from the cold drawing of tubes, give rise to premature failure and may promote corrosion at these regions. What are the causes of failure of superheater tubes? Superheater tubes are subjected to the most severe combination of stress, temperature and corrosive environment.

In addition to high-temperature strength, resistance to corrosion is also important. Failures in superheater tubes may arise from: Why supercritical boilers use less amount of steel compared to non-supercritical boilers? Supercritical boilers do not head heavy drum for separation of steam from mixture of water and steam.Put a single step to vis it the world fres h jobs here.

Just as a battery converts relatively small amounts of chemical energy into electricity for temporary or intermittent use, the FFPP converts the energy stored in fossil fuels such as coal, oil, or natural gas successively into thermal energy, mechanical energy, and finally electric energy for continuous use and distribution across a wide geographic area.

What is operating pressure? What kind of goals would you have in mind if you got this job? Deva M. What do you understand by timed cylinder lubrication?