20+ Larsen & Toubro Limited Interview Questions and Answers

There are two main types of compressors: positive displacement and dynamic.

• Positive displacement compressors work by trapping a fixed amount of air and forcing it into a smaller space, while dynamic compressors use high-speed rotating impellers to accelerate and compress air.

• Examples of positive displacement compressors include reciprocating, rotary screw, and rotary vane compressors, while examples of dynamic compressors include centrifugal and axial compressors.

• The choice o...read more

CGD stands for City Gas Distribution. It is the process of distributing natural gas to households and industries in a city.

• CGD involves laying pipelines to transport natural gas

• It includes setting up of CNG stations for vehicles

• CGD companies are responsible for maintenance and safety of pipelines

• Examples of CGD companies in India are Indraprastha Gas Limited and Mahanagar Gas Limited

Aluminium forms a protective oxide layer on its surface, preventing further corrosion.

• Aluminium reacts with oxygen in the air to form a thin layer of aluminium oxide.

• This oxide layer acts as a barrier, preventing oxygen and moisture from reaching the underlying metal.

• The oxide layer is self-repairing, as any damage to it will react with oxygen to form a new layer.

• Aluminium's corrosion resistance is further enhanced by its ability to form complex oxide structures.

• Aluminium all...read more

The Iron carbon diagram shows the relationship between temperature, carbon content, and phases of iron-carbon alloys.

• The diagram is used to predict the microstructure and properties of steel.

• It consists of three regions: austenite, ferrite, and cementite.

• The eutectoid point represents the composition of steel that transforms to pearlite upon cooling.

• Alloying elements can shift the phases and change the properties of steel.

• The diagram is essential for understanding heat treatm...read more

NDT stands for Non-Destructive Testing. It is a method of testing materials without damaging them.

• NDT is used to detect flaws or defects in materials or structures.

• It is commonly used in industries such as aerospace, automotive, and construction.

• Examples of NDT methods include ultrasonic testing, radiography, and magnetic particle inspection.

• NDT helps ensure the safety and reliability of products and structures.

• It can also save time and money by identifying issues before they...read more

CGS stands for Centimeter-Gram-Second, a system of units used in physics and engineering.

• CGS is a metric system of units based on centimeters, grams, and seconds.

• It is commonly used in physics and engineering for measuring small quantities.

• For example, in CGS, force is measured in dynes, energy in ergs, and power in ergs per second.

• CGS is not commonly used in everyday life, as the SI system is more widely used.

• However, it is still used in some specialized fields, such as astr...read more

Natural gas is a fossil fuel composed mostly of methane, while LNG and PNG are forms of natural gas that have been processed for transportation and distribution.

• Natural gas is a non-renewable energy source that is primarily composed of methane.

• LNG (liquefied natural gas) is natural gas that has been cooled to -162°C, reducing its volume by 600 times and making it easier to transport.

• PNG (piped natural gas) is natural gas that is transported through pipelines to homes and busi...read more

Third party inspection can provide unbiased evaluation and expertise in project departments.

• Third party inspections can offer unbiased evaluations of project progress and quality.

• Outsourced engineers can bring specialized expertise to the project department.

• Third party inspections can help ensure compliance with regulations and standards.

• Having a third party inspection can provide an extra layer of quality control and assurance in project departments.

The laws of thermodynamics describe how energy behaves in a system.

• First law: Energy cannot be created or destroyed, only transferred or converted.

• Second law: Entropy in a closed system will always increase over time.

• Third law: As temperature approaches absolute zero, the entropy of a system approaches a minimum value.

• Examples: A car engine converting fuel into motion (1st law), a cup of hot coffee cooling down (2nd law), absolute zero temperature (3rd law).

PE80 and PE100 are both types of polyethylene pipes used for gas and water supply, but differ in their pressure ratings and material properties.

• PE80 has a lower maximum operating pressure than PE100

• PE100 has a higher density and is more resistant to stress cracking than PE80

• PE100 is typically used for higher pressure applications such as gas distribution

• PE80 is typically used for lower pressure applications such as water supply

• Both types of pipes have similar installation and...read more

I would prioritize the emergency situation and issue the material while informing the appropriate authorities afterwards.

• Assess the urgency of the situation

• Issue the material if it is a critical emergency

• Inform the authorized personnel about the situation afterwards

• Document the incident for future reference

SDR of MDPE pipe is a ratio of the outside diameter to the wall thickness, with common types like SDR 11 and SDR 17.

• SDR stands for Standard Dimension Ratio

• It is calculated as the ratio of the outside diameter to the wall thickness of the pipe

• Common types of MDPE pipe include SDR 11, SDR 17, etc.

• Lower SDR values indicate thicker walls and higher pressure ratings

Searching on the internet involves using search engines to find information on a specific topic.

• Use keywords related to the topic you are searching for

• Utilize advanced search features like quotation marks for exact phrases or minus sign for excluding certain words

• Consider using different search engines for more comprehensive results

• Evaluate the credibility of the sources you find

• Refine your search terms if you are not getting relevant results

MDPE laying refers to the process of laying medium-density polyethylene pipes for various applications.

• Excavate the trench to the required depth and width for the MDPE pipes.

• Lay the pipes in the trench, ensuring proper alignment and support.

• Connect the pipes using appropriate fittings and secure them in place.

• Backfill the trench carefully to avoid damaging the pipes.

• Pressure test the installed MDPE system to ensure it is leak-free and functioning properly.

Important T-codes in SAP for store management

• MB51 - Material Document List

• MMBE - Stock Overview

• MM03 - Display Material Master Data

• MMBE - Stock Overview

• ME21N - Create Purchase Order

Commissioning procedure involves testing and verifying the functionality of newly installed equipment or systems.

• Develop a commissioning plan

• Verify installation and perform functional testing

• Document and resolve any issues

• Train operators and maintenance personnel

• Obtain acceptance from stakeholders

• Examples: commissioning a new HVAC system, commissioning a new power plant

The function of a DR system is to convert X-ray images into digital format for easier storage, retrieval, and sharing.

• Converts X-ray images into digital format

• Allows for easier storage, retrieval, and sharing of images

• Improves workflow efficiency in medical imaging departments

CNG stands for Compressed Natural Gas and is used as a fuel for vehicles. PNG stands for Piped Natural Gas and is used for cooking and heating in households.

• CNG is natural gas that is compressed to less than 1% of its volume at standard atmospheric pressure, making it easier to store and transport.

• CNG is commonly used as a fuel for vehicles, especially in areas where air quality is a concern.

• PNG is natural gas that is supplied through pipelines directly to homes and businesse...read more

HDPE is high-density polyethylene while MDPE is medium-density polyethylene. HDPE is more rigid and has a higher melting point compared to MDPE.

• HDPE has a higher density and is more rigid than MDPE

• HDPE has a higher melting point compared to MDPE

• MDPE is more flexible and has a lower tensile strength compared to HDPE

A service regulator is a device that controls the pressure of gas or liquid flowing through a pipeline.

• Service regulators are used in industries such as oil and gas, chemical, and pharmaceuticals.

• They can be classified into two types: single-stage and two-stage regulators.

• Single-stage regulators are used for low-pressure applications, while two-stage regulators are used for high-pressure applications.

• Examples of service regulators include Fisher, Emerson, and Honeywell regula...read more

DCS stands for Distributed Control System, used to control and monitor industrial processes.

• DCS is a computerized control system used in industries to control and monitor various processes.

• It consists of a network of controllers, sensors, and actuators that communicate with each other to control the process.

• DCS allows for centralized control and monitoring of multiple processes from a single location.

• It is commonly used in industries such as oil and gas, power generation, and...read more

DRS stands for Decision Review System, a technology used in cricket to review umpiring decisions.

• DRS allows teams to challenge umpiring decisions made on the field.

• It involves the use of technology such as ball-tracking and ultra-edge to determine the accuracy of decisions.

• Each team is allowed a limited number of unsuccessful challenges per innings.

• DRS has been a controversial topic in cricket due to its perceived inconsistencies and impact on the game.

• It has been used in int...read more

Types of compressors include reciprocating, rotary screw, and centrifugal. Natural gas is primarily composed of methane. Types of pumps include centrifugal, reciprocating, and diaphragm pumps.

• Types of compressors: reciprocating, rotary screw, centrifugal

• Composition of natural gas: primarily methane

• Types of pumps: centrifugal, reciprocating, diaphragm

There are mainly two types of CNG cylinders - Type 1 and Type 2.

• Type 1 cylinders are made of steel and have a heavy weight.

• Type 2 cylinders are made of composite materials and are lighter in weight.

• Type 2 cylinders are more expensive than Type 1 cylinders.

• Type 2 cylinders have a longer lifespan than Type 1 cylinders.

• Type 2 cylinders are more commonly used in vehicles.

• Type 1 cylinders are more commonly used in stationary applications.