Mechanical Engineering Interview Questions and Answers
Question 1-What type of pipeline is used for steam?
Answer 1– Galvani’s pipes are not commonly used for pay steam. It is better to use mild steel with screwed or welded fittings. By the way which material should be used, it is important to know the pressure and temperature of steam, because steam is a very risk factor even at low pressure.
Question 2 – Which pump capacity is good? Reciprocating of Centrifugal?
Answer 2 – In terms of efficiency, centrifugal pump is better than reciprocating pump. Because compared to the flow rate, there is more in the centrifugal than reciprocating.
It keeps the flow smooth and needs less space. At the same time, its starting coast and maintenance coast are also less.
Question 3-What is the difference between projectile speed and rocket speed?
Answer 3– The projectile does not have any motor / rocket. Therefore, it is given momentum as soon as it is launched, for example, a pen that you throw in a room. Its speed can be called interpolation.
A rocket or missile consists of a motor / rocket. So that it can accelerate itself while moving and therefore opposes other forces like gravity.
Question 5 – What is a cotter joint?
Answer 5 – This type of joint is used to connect two roads. Which are compressive and tense? The connecting road leaves are like sockets and shafts. In which both fit and the cotter is placed in the middle slot. Which connects the two pieces together?
Mechanical Engineering Interview Questions and Answers
Question 6 – What is the meaning of F.O.F in pipe design?
Answer 6 – FOF stands for Face of Flange. Flanges have two types of faces.
1 – Raised Face – Raised Face
2 – Flat – Flat Faces
FOF is used to correct errors in the measurement of vertical and horizontal pipe lines and to get the correct dimensions.
Question 7 – What is positive displacement pump mean?
Answer 7 – Conducts a certain amount of fluid from the inlet pressure of the pump to the out put discharge. This is called positive displacement pump.
Question 8 – What are the differences between pneumatics and hydraulics?
Answer 8 –
Pneumatic
Pneumatic works on air pressure. Hydraulics power is less than pneumatic power. The power of the pneumatic is met by air compressors. Oil is not compressible in pneumatic. When there is leakage in pneumatic, air spreads in the atmosphere.
Hydraulics:-
i-Hydraulics work on oil pressure.
ii-Hydraulics is smaller in size than the instrument.
iii-Hydraulics meets the power pump.
iv- In hydraulics, air is compressible.
v- If there is leakage in hydraulics, the flow fails around the instrument.
Question 9 – Why should hydraulics be used instead of pneumatic?
Answer 9 – Hydraulics work at higher pressure than pneumatic. And accurate speed is also available. In hydraulics the pressure is very unlikely to have a value change. Because you get pressure from the pump here. While compressors in pneumatic have a variation in air pressure.
Question 10 – What is isometric drawing?
Answer 10 – Isometric Drawings these are 3-D drawings. Which is used by draftsman and architect?
Mechanical Engineering Interview Questions and Answers
Question 11 – What are the benefits of gear drive?
Answer 11 – The gear drive transfers power between two shafts. Who are close to each other? While performing power transfer, its efficiency is very good. Gear drive is durable compared to belt and chain drive. Speed ratio can be changed.
Used to change speed in different load conditions.
Increases the efficiency of fuel.
Increases the efficiency of the engine.
Question 12 – What is cavitation in the pump?
Answer 12 – Vapor formation in liquids means bubbles are called cavitation.
Question 13 – What is the role of nitrogen in welding?
Answer 13 – Nitrogen is used to fill the holes during the welding process, preventing oxygen and air from entering the melted metal. Other gas is also used for this purpose. Such as organ, helium, carbon dioxide.
Question 14 – What is the mechanical advantage of double pulleys?
Answer 14 – The main advantage of double pulley is that 50% effort is enough to make a device go.
Question 15 – Why does the cavity centrifugal pump only contain? Why is it not in the depletion pump?
Answer 15 – Cavitation is formed by flow of uneven velocity and generation of bubbles. In this pump, the eye of the pump is called it is smaller than the pipe in the impeller flow area. This reduces the flow area. On, Increases the flow rate. That is why there is pressure drop on the suction and impeller of the pump. And here air cavities (Cavities) are generated. And the same goes in the air bubble pump which has cavitation in the centrifugal pump.
Mechanical Engineering Interview Questions and Answers
Question 16 – How does hydraulic clutch work?
Answer 16 – Hydraulic clutch works using compressible fluid. It acts like a solid road.
Question 17 – How can I see the pipe behind the wall?
Answer 17 – Using radio waves, we can see the pipe behind the wall.
Question 18 – What does green field project mean?
Answer 18 – Which does not harm the environment, does not spread any kind of pollution,
Which follows the environmental management system and EIA (Environmental Impact Assessment) rules in its project? This is called the Green Field Project.
Question 19 – What is the difference between hydraulic oil and engine oil?
Answer 19: Both hydraulic and engine oil are manufactured from base oil. In which the additives are mixed. Additives change the characteristics of the oil so that they function differently.
Generally, hydraulic oils (after having additives) are expected to have very low impressibility and very predictable friction and viscosity stability in pressers.
Engine oil (engine lubrication oil) is of high resistance to heat. (Due to heat including chemical and viscosity) means resistance to burning and resistance to the absorption of fuels and chemical compounds produced during combustion.
Additives are used to reduce foaming in both types of oil.
Question 20 – What skills are required for maintenance and repair technician?
Answer 20 – Safety practices and tools handling, basic calculations should be known. Must have basic knowledge of electrical and plumbing, ability to understand written or oral instructions
Question 21 – What are the challenges for maintenance work?
Answer 21 – In situations such as bad weather and temperature, one has to work in different shifts. May have to work in dirty area. Sometimes it can be physically upset and tired. You may have to work at dangerous places like working at altitude or working with electrical equipment and wires.
Question 22 – What is the work of the compressor?
Answer 22 – Compressor converts mechanical energy into pressurized energy. Sucks the air of the atmosphere and fills the air tank with high pressure. We can use air as per our requirement.
Question 23 – What is the meaning of CFM in Compressor?
Answer 23 – CFM’s flower name is Cubic Feet per Minute. This is the capacity of the air produced by the compressor. Which is measured in PSI?
Question 24 – How is air leakage checked?
Answer 24 – Soap Solution is applied in the joint of air pipeline and in the fitting connector. If the bubbles are found at that place. So there are considered leakages.
Mechanical Engineering Interview Questions and Answers
Question 25 – What is gear? And what is his job?
Answer 25 – The gear is a mechanical device. It is an important part of any device. Which transmits power torque? It is a medium to operate from one device to another. There is a tooth above the gear. Who connect to each other? Currently the best tool for transmitting power without slipping is gear. Which is the most used?
Question 26 – What are the types of gears?
Answer 26 –
1 – Super Gear
2 – Rack and pinion gear
3 – Spur Gear
4 – Helical Gear
5 – Bevel Gear
Question 27 – How to eliminate cavity in the pump?
Answer 27 – Cavity means generation of bubbles in any fluid. To overcome cavitation, we have to increase the size of the pump by 1 to 2 inches. The pressure of the suction head has to be increased and the pump speed has to be reduced.
Question 28 – Why is a Centrifugal Pump called a High Discharge Pump?
Answer 28 – The centrifugal pump is a kinetic device. This type of pump uses centrifugal forces to push the fluid. Therefore, the fluid that is used also moves through the same energy through the rotating impeller. The action of centrifugal moves the fluid to a higher velocity by inducing the impeller. In other words, it converts mechanical energy into liquid energy. And it discharges the liquid in a high rate.
Formula -Centrifugal force F= (M*V2)/R.
M – Mass
V – Velocity
R – Radios
Question 29 – Why does the cavity centrifugal pump have a Q? Why is it not in a depletion pump?
Answer 29 – Cavitation is formed by flow of uneven velocity and generation of bubbles. In this pump, the eye of the pump is called it is smaller than the pipe in the impeller flow area. This reduces the flow area. On, Increases the flow rate. That is why there is pressure drop on the suction and impeller of the pump. And here air cavities (Cavities) are generated. And the same goes in the air bubble pump which has cavitation in the centrifugal pump.
Question 30 – What is kinematic viscosity?
Answer 30 – The ratio of viscosity and density of a fluid is called kinematic viscosity.
