Raichem Medicare Maintenance Engineer Interview Questions, Process, and Tips

The refrigeration cycle used in a chilling plant is typically the vapor compression cycle.

• The vapor compression cycle involves compressing refrigerant vapor to increase its temperature and pressure.

• The high-pressure vapor then condenses into a liquid, releasing heat.

• The liquid refrigerant then passes through an expansion valve, reducing its pressure and temperature.

• The low-pressure liquid then evaporates, absorbing hea...read more

A vapour compression cycle is a process used in refrigeration systems to remove heat from a space.

• The cycle consists of four main components: a compressor, a condenser, an expansion valve, and an evaporator.

• The compressor takes in low-pressure refrigerant gas and compresses it to high pressure.

• The high-pressure gas then flows to the condenser, where it releases heat and condenses into a high-pressure liquid.

• The liquid ...read more

Preventive maintenance of a reactor involves regular inspection, cleaning, and replacement of parts to ensure safe and efficient operation.

• Regular inspection of reactor components such as valves, pumps, and pipes

• Cleaning of reactor surfaces to prevent buildup of contaminants

• Replacement of worn or damaged parts to prevent equipment failure

• Testing of safety systems to ensure proper function in case of emergency

• Monitoring...read more

Utility and process equipment capacity and make

• Provide details of all utility and process equipment installed in the facility

• Include information on their capacity and make

• Utility equipment may include HVAC, compressed air, water treatment, etc.

• Process equipment may include reactors, distillation columns, pumps, etc.

Air fuel ratio in boiler is the ratio of mass of air to mass of fuel. It is maintained by adjusting the fuel and air flow rates.

• Air fuel ratio is critical for efficient combustion and minimizing emissions.

• The ideal air fuel ratio for a boiler is typically between 1.5 and 2.5.

• To maintain the air fuel ratio, the fuel and air flow rates must be adjusted based on the boiler load and combustion conditions.

• Excess air can lea...read more

Yes, chemical treatment is done in cooling tower to prevent scaling, corrosion and biological growth.

• Chemicals like biocides, scale inhibitors and corrosion inhibitors are added to the water in cooling tower.

• Biocides are used to prevent the growth of bacteria, algae and fungi.

• Scale inhibitors are used to prevent the formation of mineral deposits on the tower walls and heat exchangers.

• Corrosion inhibitors are used to pr...read more

HVAC capacity and motor size are interdependent.

• The HVAC capacity is determined by the size of the space it needs to cool or heat.

• The motor size is determined by the HVAC capacity and the type of system being used.

• For example, a small window AC unit may have a motor size of 1/6 horsepower, while a large central AC unit may have a motor size of 5 horsepower.

• It is important to ensure that the motor size is appropriate fo...read more

Gate valves and ball valves are two common types of valves used in industrial applications.

• Gate valves have a sliding gate that controls the flow of fluid through the valve.

• Ball valves have a rotating ball with a hole in the middle that controls the flow of fluid through the valve.

• Gate valves are typically used for on/off control of fluid flow, while ball valves are used for throttling and control applications.

• Gate val...read more

Yes, I have experience in boiler passing. It involves a thorough inspection of the boiler to ensure its safe and efficient operation.

• Boiler passing involves a visual inspection of the boiler's exterior and interior components.

• The inspection includes checking for leaks, cracks, corrosion, and other signs of wear and tear.

• The boiler's safety controls, valves, and gauges are also checked to ensure they are functioning pro...read more

Enthalpy is the sum of internal energy and the product of pressure and volume.

• Enthalpy is a thermodynamic property of a system.

• It is represented by the symbol 'H'.

• It is defined as the sum of internal energy and the product of pressure and volume.

• Enthalpy change is the heat absorbed or released during a chemical reaction.

• Enthalpy is used in various fields including chemistry, physics, and engineering.

Validation ensures that a process or system meets the intended requirements, while qualification ensures that the equipment or system is installed and operates correctly.

• Validation is focused on the process or system, while qualification is focused on the equipment or system.

• Validation ensures that the process or system meets the intended requirements, while qualification ensures that the equipment or system is install...read more

Pressure differential is the difference in air pressure between two points in an HVAC system.

• It is important for maintaining proper airflow and ventilation.

• It can be measured using a manometer.

• A high pressure differential can indicate a clogged filter or duct.

• A low pressure differential can indicate a malfunctioning fan or blower.

• It is often used in cleanroom environments to prevent contamination.

There are several types of pumps including centrifugal, positive displacement, and axial flow pumps.

• Centrifugal pumps use a rotating impeller to create a flow of fluid.

• Positive displacement pumps move fluid by trapping a fixed amount and forcing it through the discharge port.

• Axial flow pumps move fluid parallel to the pump shaft.

• Other types of pumps include reciprocating pumps, peristaltic pumps, and jet pumps.

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

• Positive displacement compressors work by trapping air in a chamber and reducing the volume of the chamber to compress the air. Examples include reciprocating, rotary screw, and rotary vane compressors.

• Dynamic compressors work by imparting velocity to the air and then converting that velocity into pressure. Examples include centrifugal and axial...read more

HVAC stands for Heating, Ventilation, and Air Conditioning.

• HVAC is a system used for regulating temperature, humidity, and air quality in buildings.

• It includes components such as furnaces, air conditioners, ductwork, and thermostats.

• HVAC systems can be found in residential, commercial, and industrial buildings.

• Proper maintenance of HVAC systems is important for energy efficiency and indoor air quality.

A typical water system diagram includes a water source, treatment plant, distribution network, and end-users.

• Water source can be a river, lake, or groundwater well

• Treatment plant removes impurities and disinfects water

• Distribution network includes pipes, pumps, and storage tanks

• End-users can be residential, commercial, or industrial

• Backflow prevention devices are installed to prevent contamination

Breakdowns in chillers can be caused by various factors such as electrical issues, refrigerant leaks, and mechanical failures.

• Electrical issues such as faulty wiring or blown fuses can cause breakdowns in chillers.

• Refrigerant leaks can occur due to corrosion or damage to the chiller's components.

• Mechanical failures such as worn out bearings or broken belts can also cause breakdowns in chillers.

• Dirty or clogged filters ...read more

Boiler efficiency is the ratio of energy output to energy input.

• Efficiency is important for reducing fuel consumption and costs.

• Factors affecting efficiency include combustion efficiency, thermal efficiency, and fuel-to-steam efficiency.

• Regular maintenance and cleaning can improve efficiency.

• For example, reducing excess air can improve combustion efficiency.

• Another example is using economizers to recover heat from flue...read more

There are various types of seals used in different industries and applications.

• Mechanical seals: used to prevent leakage between rotating and stationary parts, commonly used in pumps and compressors.

• Hydraulic seals: used to prevent fluid leakage in hydraulic systems, commonly used in cylinders and valves.

• O-ring seals: used to create a seal between two mating surfaces, commonly used in plumbing and automotive applicatio...read more