800+ Mechanical Engineer Interview Questions and Answers

The refrigerant used in car air conditioning systems is called R-134a.

• R-134a is a type of hydrofluorocarbon (HFC) refrigerant commonly used in car air conditioning systems.

• It replaced the previously used R-12 refrigerant due to its ozone-depleting properties.

• R-134a is non-ozone depleting and considered more environmentally friendly.

• It has a lower global warming potential compared to other refrigerants.

• R-134a is also used in other cooling systems such as refrigerators and free...read more

Various types of sensors are used in glue units within the corrugation box industry for monitoring and controlling the glue application process.

• Pressure sensors are used to monitor the pressure of the glue being applied.

• Temperature sensors are used to ensure the glue is at the correct temperature for application.

• Flow sensors are used to measure the flow rate of the glue.

• Level sensors are used to monitor the amount of glue in the reservoir.

• Viscosity sensors can be used to ensu...read more

Roller screen maintenance involves regular cleaning, lubrication, and inspection.

• Clean the rollers and screen regularly to prevent buildup of debris and dirt.

• Lubricate the rollers and bearings to ensure smooth operation.

• Inspect the rollers, bearings, and screen for wear and damage.

• Replace any worn or damaged parts immediately to prevent further damage.

• Follow manufacturer's guidelines for maintenance and schedule regular maintenance checks.

• Train personnel on proper maintenance...read more

The least count of a vernier caliper is the smallest measurement that can be accurately read on the scale.

• The least count is determined by the number of divisions on the main scale and the vernier scale.

• It is calculated by dividing the smallest division on the main scale by the number of divisions on the vernier scale.

• For example, if the smallest division on the main scale is 0.1 mm and the vernier scale has 10 divisions, the least count would be 0.01 mm.

• The least count repre...read more

The clearance for big end bearing can be measured using a micrometer or a feeler gauge.

• Use a micrometer to measure the diameter of the crankshaft journal and the inner diameter of the big end bearing. The clearance is calculated by subtracting the crankshaft journal diameter from the bearing inner diameter.

• Alternatively, a feeler gauge can be used to measure the clearance by inserting the gauge between the crankshaft journal and the bearing and checking for the appropriate ga...read more

Micromaterials refer to materials with microscale dimensions, typically less than 100 micrometers.

• Micromaterials have unique properties due to their small size, such as increased surface area to volume ratio and altered mechanical, electrical, and optical properties.

• Examples of micromaterials include microelectromechanical systems (MEMS), microfluidic devices, and microscale sensors.

• Research in micromaterials has applications in fields such as biotechnology, electronics, and ...read more

Possible causes and solutions for poor pickup issue in a vehicle

• Causes: clogged air filter, dirty fuel injectors, faulty spark plugs, low fuel pressure

• Solutions: replace air filter, clean fuel injectors, replace spark plugs, check fuel pump

• Example: A clogged air filter can restrict airflow to the engine, leading to poor pickup

A differential diagram shows the relationship between two variables and their rates of change.

• It is commonly used in calculus to solve problems involving rates of change.

• The diagram consists of two axes, one for each variable, and a curve representing their relationship.

• The slope of the curve at any point represents the rate of change of the variables at that point.

• Examples of applications include physics, economics, and engineering.

• Differential diagrams can also be used to v...read more

Steps to create a 3D model of a Steering wheel in CAD software.

• Start by creating a new file in the CAD software.

• Sketch the basic shape of the steering wheel using tools like lines, arcs, and circles.

• Extrude the sketch to give it depth and create a 3D shape.

• Add details such as grips, buttons, and logos using additional sketches and features.

• Apply materials and textures to make the model realistic.

• Check for any errors or issues in the model and make necessary adjustments.

• Save t...read more

Bearings are used to reduce friction between two moving parts. There are several types of bearings.

• Bearings are used to support and reduce friction between two moving parts

• They come in different types such as ball bearings, roller bearings, and plain bearings

• Ball bearings are used in applications with low load and high speed

• Roller bearings are used in applications with high load and low speed

• Plain bearings are used in applications with high load and low speed where lubricatio...read more

Quality control is a process used to ensure that products or services meet specified requirements and standards.

• Quality control involves monitoring and testing products or services to ensure they meet predetermined standards

• It helps identify defects or errors in the production process

• Quality control aims to prevent defects and improve the overall quality of products or services

• Examples include inspecting products for defects, conducting tests to ensure functionality, and impl...read more

Yes, I have experience in batching plant erection for 3 years.

• I have worked on the erection of batching plants for 3 years

• I am familiar with the process of setting up and installing batching plants

• I have experience in troubleshooting and maintenance of batching plants

• I have knowledge of the safety protocols and regulations related to batching plant erection

Cycle time for CNC machining can be calculated using the formula: cycle time = (total cutting time + tool change time + setup time + inspection time) / total parts

• Total cutting time is the time taken to complete the machining process for one part

• Tool change time is the time taken to change the tool between different operations

• Setup time is the time taken to set up the machine for the machining process

• Inspection time is the time taken to inspect the finished part

• Total parts is...read more

T.G equipment maintenance involves regular inspections, cleaning, lubrication, and replacement of worn-out parts.

• Perform regular inspections to identify any signs of wear and tear

• Clean the equipment regularly to prevent the buildup of dirt and debris

• Lubricate the moving parts to reduce friction and prevent damage

• Replace any worn-out parts to prevent equipment failure

• Follow the manufacturer's recommended maintenance schedule

• Train personnel on proper maintenance procedures

The least count of vernier caliper is 0.02 mm and that of micrometer is 0.01 mm.

• Vernier caliper has a least count of 0.02 mm.

• Micrometer has a least count of 0.01 mm.

• Least count is the smallest measurement that can be read on the instrument.

• It is important to consider the least count while taking measurements for accuracy.

Answering questions on Vogele paver screed function and diesel engine BS iv & BS VI

• Vogele paver screed function involves leveling and compacting asphalt or concrete surfaces

• Temper/pressure bar applications involve adjusting the temperature and pressure of the screed to achieve desired results

• BS IV and BS VI are emission standards for diesel engines, with BS VI being more stringent and requiring advanced technology to reduce emissions

• The main difference between BS IV and BS VI...read more

Lower limit and upper limit are the minimum and maximum values within a given range or set of values.

• Lower limit refers to the minimum value that can be reached or considered.

• Upper limit refers to the maximum value that can be reached or considered.

• These limits define the boundaries or constraints of a particular system or measurement.

• For example, in temperature measurement, the lower limit could be -40 degrees Celsius and the upper limit could be 100 degrees Celsius.

Electric motor production started in the late 19th century and has since evolved with advancements in technology.

• Electric motor production began in the late 19th century.

• The first practical electric motor was developed by Thomas Davenport in 1834.

• Advancements in technology have led to the development of more efficient and powerful electric motors.

• Electric motor production has grown significantly with the rise of electric vehicles and renewable energy sources.

Shear force and bending moment vary linearly along the length of a cantilever beam with a point load at the free end.

• Shear force is constant along the length of the beam until the point load, then it decreases linearly to zero at the free end.

• Bending moment is zero at the fixed end, increases linearly to a maximum at the point load, and then decreases linearly to zero at the free end.

The number of gaskets in a floating head heat exchanger varies depending on the design and size of the exchanger.

• The number of gaskets is typically determined by the number of tube passes in the heat exchanger.

• Each tube pass may require multiple gaskets, depending on the design.

• The gaskets are used to create a seal between the floating head and the tube sheet.

• The number of gaskets can range from a few to several dozen, depending on the size and complexity of the heat exchange...read more

Aluminium stress strain curve shows its elastic and plastic deformation behavior under stress.

• Aluminium has a linear elastic region up to a certain point, beyond which it undergoes plastic deformation.

• The yield strength of aluminium is around 40-90 MPa.

• Ultimate tensile strength of aluminium is around 90-200 MPa.

• Aluminium has a low modulus of elasticity compared to steel.

• The stress strain curve of aluminium can be affected by factors such as temperature and strain rate.

Gearbox is a mechanical device that transmits power from an engine to the wheels by changing the speed and torque of the output shaft.

• It provides torque multiplication and speed reduction.

• It allows the engine to operate at its most efficient speed.

• It enables the vehicle to move at different speeds and climb hills.

• It protects the engine and transmission from damage by absorbing shock loads.

• Types of gearbox include manual, automatic, and continuously variable transmission (CVT)...read more

TDC stands for Top Dead Center and BDC stands for Bottom Dead Center. They are reference points in the rotation of an engine's crankshaft.

• TDC is the point where the piston is at its highest position in the cylinder during the compression stroke.

• BDC is the point where the piston is at its lowest position in the cylinder during the exhaust stroke.

• Understanding TDC and BDC is crucial for timing engine components such as valves and ignition.

• TDC and BDC are used to determine the p...read more

The clearance of TDC and BDC for a vertical reciprocating compressor can be measured using a dial indicator.

• Use a dial indicator to measure the distance between the top dead center (TDC) and bottom dead center (BDC) positions of the piston.

• Rotate the crankshaft to bring the piston to TDC and set the dial indicator to zero.

• Rotate the crankshaft to bring the piston to BDC and note the reading on the dial indicator.

• The difference between the readings at TDC and BDC will give you...read more

Focus on proper alignment, tightness, material compatibility, and proper torque during suction and discharge valve box up.

• Ensure proper alignment of the valves to prevent leakage

• Check for tightness of the connections to avoid any leaks

• Use materials compatible with the fluid being handled to prevent corrosion or damage

• Apply the correct torque to the bolts to ensure a secure connection

25 KV AC is more efficient for railways due to lower energy losses over long distances.

• 25 KV AC is more efficient for long distance transmission as it experiences lower energy losses compared to 750V DC.

• 25 KV AC allows for higher speeds and heavier loads on the railway system.

• 25 KV AC is the standard voltage used in many modern railway systems around the world, such as in Europe and parts of Asia.

• 750V DC may be more suitable for urban transit systems with shorter distances be...read more

Designed a chair for a class that is comfortable, durable, and ergonomic.

• Consider the height of the desk and the average height of the students

• Use materials that are sturdy and easy to clean

• Incorporate lumbar support and adjustable features for comfort

• Add armrests for additional support

• Ensure the chair has a non-slip base for safety

Design a system with insulation to minimize heat transfer in vessel under convection and radiation conditions.

• Use insulation materials with low thermal conductivity to reduce heat transfer

• Incorporate reflective surfaces to minimize radiation heat transfer

• Optimize the design to minimize surface area exposed to convection and radiation

• Consider using double-walled vessels with a vacuum between walls for better insulation

Improper rolls elongation can cause waveness in pipes during production.

• Rolls elongation is the process of stretching the metal sheet to the desired thickness.

• If the elongation is not proper, it can cause uneven thickness and waveness in the pipes.

• This can lead to defects in the final product and affect its performance.

• Proper calibration and maintenance of the rolling equipment can prevent this issue.

• Regular inspection and quality control can also help identify and address an...read more

The amount of engine oil used in a 210 Excavator for engine service varies depending on the specific model and maintenance requirements.

• The amount of engine oil needed for engine service in a 210 Excavator can be found in the manufacturer's specifications or service manual.

• It is important to follow the recommended oil change intervals and use the appropriate grade and quantity of oil.

• The engine oil capacity may also depend on factors such as the size of the engine and the ope...read more

The capacity of each hopper, diameter and length of belt conveyor, capacity of gearbox motor load, and RPM are important factors in mechanical engineering.

• Capacity of each hopper refers to the maximum amount of material it can hold at one time.

• Diameter and length of belt conveyor determine the amount and speed of material that can be transported.

• Capacity of gearbox motor load indicates the maximum load the motor can handle.

• RPM (Revolutions Per Minute) is the speed at which th...read more

The time required for the erection of a 1000mtrs belt conveyor structure trassel assembly work and gallery assembly work depends on the manpower available.

• The time of erection will vary based on the experience and efficiency of the workers involved.

• Factors such as complexity of the structure, availability of equipment, and coordination among the team members will also impact the assembly time.

• For example, if there are skilled workers with prior experience in similar projects,...read more

The coding test has been implemented through an online platform.

• The coding test is conducted through an online platform.

• Candidates are given a set of coding problems to solve within a specified time limit.

• The platform automatically evaluates the code and provides instant feedback.

• The test may include multiple choice questions or require the candidate to write code from scratch.

• The coding test is designed to assess the candidate's programming skills and problem-solving abiliti...read more

Types of manufacturing include additive manufacturing, subtractive manufacturing, and formative manufacturing.

• Additive manufacturing: building up materials layer by layer, such as 3D printing

• Subtractive manufacturing: removing material from a solid block to create the final product, such as CNC machining

• Formative manufacturing: shaping materials into the desired form, such as forging or casting

The second law of thermodynamics states that the entropy of an isolated system always increases over time.

• Entropy always increases in natural processes

• Heat flows from hot to cold

• Efficiency of heat engines is limited by the second law

• Entropy can be thought of as a measure of disorder or randomness

• Examples: melting ice, diffusion of gases, irreversible processes

SS 304 and SS 316 are both stainless steel alloys, but with different compositions and properties.

• SS 304 contains 18% chromium and 8% nickel, while SS 316 contains 16% chromium, 10% nickel, and 2% molybdenum.

• SS 316 is more corrosion-resistant than SS 304, especially in environments with chlorides or acids.

• SS 316 is more expensive than SS 304.

• SS 304 is commonly used in food processing equipment, while SS 316 is used in marine and chemical processing industries.

Balling disc maintenance involves regular inspection, cleaning, and lubrication to ensure optimal performance.

• Inspect the disc for wear and tear regularly

• Clean the disc and surrounding area to prevent buildup of debris

• Lubricate the disc and bearings as per manufacturer's recommendations

• Check for proper alignment and adjust if necessary

• Replace worn out parts as needed

Air flow in HVAC ducting can be calculated using the formula Q = AV

• Q = air flow rate in cubic feet per minute (CFM)

• A = cross-sectional area of the duct in square feet

• V = air velocity in feet per minute (FPM)

• Air velocity can be measured using a pitot tube or an anemometer

• Duct sizing and layout can affect air flow and should be considered in calculations

The Internet is a global network of interconnected computers and devices that allows for communication and sharing of information.

• The Internet is a network of networks, connecting billions of devices worldwide

• Companies and industries typically use a combination of local area networks (LANs) and wide area networks (WANs)

• LANs are used within a single location, such as an office building, while WANs connect multiple locations across a wider area

• Examples of network technologies u...read more

Surface finish is required in various applications for improved functionality and aesthetics.

• Surface finish is important in manufacturing to improve the performance and durability of products.

• In automotive industry, surface finish is required for improved aerodynamics and fuel efficiency.

• In medical devices, surface finish is crucial for preventing bacterial growth and ensuring biocompatibility.

• Surface finish is also important in consumer products for aesthetic appeal and tact...read more

The welding electrode used in piping depends on the type of material being welded.

• For carbon steel piping, E7018 electrodes are commonly used

• For stainless steel piping, E308L electrodes are commonly used

• For high-strength piping, E8018 electrodes are commonly used

• The electrode must match the material being welded to ensure proper strength and durability

• Other factors such as welding position and joint design may also affect electrode selection

RT, UT, and magnetic partials are non-destructive testing methods used in engineering.

• RT stands for Radiographic Testing and uses X-rays or gamma rays to inspect the internal structure of a material.

• UT stands for Ultrasonic Testing and uses high-frequency sound waves to detect flaws or defects in a material.

• Magnetic particle testing uses magnetic fields and iron particles to detect surface and slightly subsurface defects in ferromagnetic materials.

• These methods are used to en...read more

To detect boiler superheater tube leakage, inspect for steam or water leakage. Bed coil tubes thickness can be identified using ultrasonic testing. Coal handling plant questions may include equipment and safety measures.

• Inspect for steam or water leakage to detect boiler superheater tube leakage

• Use ultrasonic testing to identify bed coil tubes thickness

• Coal handling plant questions may include equipment and safety measures

• Examples of coal handling plant equipment include crus...read more

The bearing types used in axially split centrifugal pumps are mainly ball bearings and sleeve bearings.

• Ball bearings are commonly used in axially split centrifugal pumps due to their high load capacity and low friction.

• Sleeve bearings, also known as journal bearings, are used in pumps that operate at lower speeds and lower loads.

• Other types of bearings, such as roller bearings, may also be used depending on the specific pump design and requirements.

The steering system in automobiles allows the driver to control the direction of the vehicle by turning the front wheels.

• The steering wheel is connected to the steering column, which is connected to the steering gear.

• The steering gear translates the rotational motion of the steering wheel into lateral motion of the front wheels.

• There are different types of steering systems such as rack and pinion, recirculating ball, and power steering.

• Power steering uses hydraulic or electri...read more

The procedure to install centrifugal axial compressors involves proper planning, alignment, assembly, and testing.

• Ensure proper foundation is prepared to support the compressor

• Align the compressor with the piping system for proper flow

• Assemble the compressor components according to manufacturer's instructions

• Test the compressor for performance and efficiency before final installation

A trickling filter is a type of wastewater treatment system that uses a bed of rocks or plastic media to promote the growth of bacteria that break down organic matter.

• Select a suitable location for the trickling filter system

• Design the filter bed with appropriate media such as rocks or plastic

• Install a distribution system to evenly distribute wastewater over the filter bed

• Provide a system for collecting treated effluent and removing excess sludge

• Monitor and maintain the syste...read more