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Mechanical Engineering Interview Questions part – 8


innocently Welcome to the 8th ! Part of the http://harbutlawcottages.co.uk/special-offers.php Mechanical Engineering Questions . These Questions are useful for mechanical objective and written exams. If you are to be appeared to be in viva-voce  for mechanical engineering profession then go through all the links provided in this article.

Basic Mechanical Engineering Interview Questions

basic mechanical engineering interview questions

  • In IC engine which part is known as column?

Answer: In IC engine the connecting rod is known as the column.

  • What is the function of orifice meter?

Answer: The orifice meter or orifice plate is used for measuring flow rate of a fluid. It is also used for flow restriction and pressure reducing purpose.

  • What is Vena Contracta?

Answer: When fluid is passed through the flow meters like orifice or nozzles there is a point in the fluid stream where the diameter of the stream is minimum and velocity is maximum. In this place we find the least cross sectional area. This is known as the vena contracta.

  • How to identify petrol and diesel engines.

Answer: There are many differences in the running cycle of the two engine types. Petrol engine is spark ignition and Diesel engine is compression ignition. Petrol engine = Otto cycle and Diesel engine = Diesel cycle.

But the difference between them which is visible practically is the presence of spark plug on the petrol engine. Diesel engine doesn’t have a spark plug it has an atomizer.

  • Mention some desirable properties of Coal.


  1. Coals needs to have high calorific values
  2. They should be of low sulfur content.
  3. Low ash content.
  4. Sometimes the coal is needed to be grinded before use. It should have good grindability.
  • What are the main classification of coals?

Answer: According to the rank the coal is classified as – Peat, Lignite, Sub-bituminous, Bituminous and Anthracite. Peat has the lowest rankings and Anthracite has the highest.

  • How the rank of the coal is obtained?

Answer: The rank of the coal is determined by the Carbon: Hydrogen ratio. The ratio of the carbon increase from 75% to 93 % and the hydrogen content decreases from 20 % to 3 %

  • Give the Equation of generator that includes pole numbers, frequency and synchronous speed generator.

Answer: N = 120f / P (N = synchronous speed, P = No of poles, f = Frequency)

  • Draw schematic diagram of air standard gas turbine with regeneration. Show the T-s Diagram.

Answer: Please follow this link. Gas Turbine Cycle with reheat , regeneration and intercooling

  • Show a Typical Composition of different types of coals.


basic mechanical engineering -composition of coals

  • What is deaerator? Mention its functions.

Answer: For a boiler to run smoothly, the feedwater must be free from contaminants. Feedwater contains dissolved gases which can be proved very detrimental for the boiler material. Dissolved gases in the boiler feedwater can be of corrosive nature. In these cases deaerator can be proved very useful. Deaerators are the devices that remove dissolved gases from the boiler feed water. Corrosion can be minimized by reducing the amount of oxygen and carbon dioxide to a level where the corrosive nature of the gases is minimized.

  • What is Higher Heating Value (HHV) and Lower Heating Value (LLV) and Gross Heating value (GHV)?

Answer : Please follow the links . Higher and Lower Calorific Value 

  • What is HFO, FFO, LDO and HSD?

Answer: HFO = Heavy Fuel Oil, FFO = Furnace Fuel Oil, HSD = High Speed Diesel, LDO = Light Diesel Oil.

Hope these basic mechanical engineering interview questions will help you . Stay tuned . More articles are coming.

Basic Mechanical Engineering is a small endeavor for the mechanical engineering students and fresh graduates. All the articles are written by mechanical "rocking" engineers \m/

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