Larsen & Toubro Limited Mechanical Supervisor Interview Questions and Answers

Gpm for water supply pump can be calculated by dividing the flow rate in gallons by the time in minutes.

• Calculate the flow rate in gallons per minute (GPM)

• Determine the time in minutes over which the flow rate is measured

• Divide the flow rate by the time to get the GPM value

Heat exchangers are devices used to transfer heat between two or more fluids, ensuring efficient heat transfer and temperature control.

• Transfer heat between fluids

• Maintain temperature control

• Increase energy efficiency

• Commonly used in HVAC systems, refrigeration units, and chemical processing plants

A lathe is a machine tool that rotates a workpiece about an axis of rotation to perform various operations such as cutting, sanding, drilling, knurling, or deformation.

• Lathe is used to shape and cut materials such as wood, metal, and plastic.

• It rotates the workpiece on its axis and a cutting tool is applied to the workpiece to remove material.

• Lathe can perform various operations such as turning, facing, drilling, borin...read more

Boiler drum is a cylindrical container which is used to store water and steam produced in a boiler.

• It is a vital component of a boiler system.

• It is usually made of steel and is located at the top of the boiler.

• It acts as a reservoir of water/steam and helps to separate steam from water.

• It also helps to regulate the pressure and temperature of the steam.

• The level of water in the drum is maintained by a feedwater control...read more

An Air Handling Unit (AHU) consists of several parts that work together to condition and circulate air.

• Filter section: Removes dust and particles from the air.

• Heating coil: Warms the air before it is distributed.

• Cooling coil: Cools the air before it is distributed.

• Humidifier: Adds moisture to the air if needed.

• Fan: Circulates the air through the AHU.

• Dampers: Control the flow of air.

• Mixing chamber: Mixes outside and ret...read more

ACPH stands for Air Changes Per Hour.

• ACPH is a measurement used to determine the rate at which the air in a space is replaced with fresh air.

• It is commonly used in HVAC systems to ensure proper ventilation and air quality.

• ACPH is calculated by dividing the volume of air in a space by the flow rate of fresh air into that space.

• For example, if a room has a volume of 1000 cubic feet and fresh air is supplied at a rate of ...read more

The recommended ACPH for a kitchen depends on the size and type of kitchen.

• The recommended ACPH for a commercial kitchen is 15-20 ACPH (air changes per hour).

• The size and type of kitchen, as well as the type of cooking equipment used, can affect the recommended ACPH.

• The ACPH can be calculated by dividing the volume of the kitchen by the airflow rate.

• Proper ventilation and exhaust systems should be in place to maintain ...read more

VAV stands for Variable Air Volume.

• VAV is a type of HVAC system that varies the airflow to different zones based on their heating and cooling needs.

• It uses dampers to control the amount of air flowing into each zone.

• VAV systems are energy-efficient and can save money on heating and cooling costs.

• They are commonly used in commercial buildings and large residential buildings.

• VAV systems can be controlled by a building au

VAV stands for Variable Air Volume. It is an HVAC system that controls the airflow to different zones based on their heating and cooling needs.

• VAV uses a series of dampers to regulate the amount of air flowing into a space.

• It measures the temperature of the air in each zone and adjusts the airflow accordingly.

• VAV systems are energy-efficient as they only supply the amount of air required to maintain the desired tempera...read more

The thumb rule to calculate water consumption in a cooling tower is 3 GPM per every 100 tons of cooling.

• Water consumption in cooling tower is calculated based on the cooling load

• The thumb rule is 3 GPM per every 100 tons of cooling

• Factors like temperature, humidity, and air flow rate affect water consumption

• Water treatment and maintenance can also impact water consumption

Parameters considered while calculating heat load in a room

• Size of the room

• Number of occupants

• Type and number of electrical appliances

• Number and size of windows

• Insulation of walls and ceiling

• Orientation of the room

• Climate of the region

Directions affect the amount of heat transferred and the efficiency of the system.

• Heat transfer is affected by the direction of the flow of fluids or gases.

• The orientation of the surface being heated or cooled affects the amount of heat transferred.

• The direction of the sun's rays can affect the heat load on a building.

• The direction of wind flow affects the heat load on a building.

• Considering directions helps in designi

Alignment methods are techniques used to ensure proper positioning and orientation of mechanical components.

• Common alignment methods include laser alignment, dial indicator alignment, and straight edge alignment.

• Laser alignment uses a laser beam to measure and adjust the alignment of components.

• Dial indicator alignment uses a dial gauge to measure the alignment of components.

• Straight edge alignment involves using a str...read more