Shyam Sel & Power Interview Questions, Process, and Tips

Types of lubrication include hydrodynamic, boundary, and mixed lubrication.

• Hydrodynamic lubrication occurs when a fluid film separates the moving surfaces, such as in engines.

• Boundary lubrication involves a thin layer of lubricant that prevents direct contact between surfaces, like in metal cutting.

• Mixed lubrication combines elements of both hydrodynamic and boundary lubrication, commonly found in many mechanical syste

Lubrication grades of grease and gear oil

• Grease lubrication grades are NLGI 000, 00, 0, 1, 2, 3

• Gear oil lubrication grades are classified by the American Petroleum Institute (API) as GL-1, GL-2, GL-3, GL-4, GL-5, and GL-6

• The higher the number, the more viscous the lubricant

The support roller bearing number depends on the specific application and load requirements.

• The bearing number should be selected based on the load capacity and speed requirements of the support roller.

• Factors such as temperature, lubrication, and alignment should also be considered when selecting a bearing.

• Examples of support roller bearings include cylindrical roller bearings, spherical roller bearings, and needle ro

The support roller bore diameter is the size of the hole in the center of the support roller.

• The bore diameter is important for selecting the appropriate bearing size.

• It is also important for ensuring proper alignment and fit with the shaft.

• The bore diameter can vary depending on the size and type of support roller.

• For example, a small support roller may have a bore diameter of 1 inch, while a larger one may have a bor

Types of vibration include free, forced, damped, and self-excited.

• Free vibration occurs when a system oscillates on its own without any external force.

• Forced vibration occurs when a system is subjected to an external force.

• Damped vibration is when the amplitude of vibration decreases over time due to energy dissipation.

• Self-excited vibration occurs when a system vibrates due to its own internal forces, such as in a gui

Viscosity is the measure of a fluid's resistance to flow.

• Viscosity is affected by temperature and pressure.

• It is measured in units of poise or centipoise.

• High viscosity fluids are thick and flow slowly, while low viscosity fluids are thin and flow quickly.

• Examples of high viscosity fluids include honey and molasses, while water and alcohol are low viscosity fluids.

Viscosity is measured in units of poise or centipoise.

• Viscosity is a measure of a fluid's resistance to flow.

• The unit of viscosity is poise or centipoise.

• Water has a viscosity of 1 centipoise at room temperature.

• Honey has a viscosity of around 2000 centipoise.

• Viscosity can be affected by temperature and pressure.

Density unit is the measure of mass per unit volume of a substance.

• Density unit is expressed in kg/m³ or g/cm³.

• It is used to compare the mass of different substances with the same volume.

• Commonly used in industries like construction, oil and gas, and pharmaceuticals.

• Example: The density of water is 1000 kg/m³ or 1 g/cm³.

Various types of breakdown can occur in a crusher.

• Mechanical breakdown due to wear and tear of components

• Electrical breakdown due to faulty wiring or components

• Hydraulic breakdown due to leaks or malfunctioning of hydraulic system

• Material breakdown due to foreign objects or excessive feed size

• Operational breakdown due to improper use or maintenance

• Examples include bearing failure, motor burnout, hydraulic cylinder fail

The gear ratio of the main drive oil gearbox is typically specified by the manufacturer.

• The gear ratio determines the speed and torque of the output shaft relative to the input shaft.

• It is important to select the appropriate gear ratio for the application to ensure optimal performance.

• The gear ratio can be calculated by dividing the number of teeth on the output gear by the number of teeth on the input gear.

• For example...read more

A pneumatic cylinder is a mechanical device that uses compressed air to produce force in a reciprocating linear motion.

• Pneumatic cylinders are commonly used in industrial automation and robotics.

• They are often used to move and position objects, as well as to apply force.

• Pneumatic cylinders come in various sizes and shapes, including single-acting and double-acting cylinders.

• They can be made from materials such as alumi...read more

Impactor capacity refers to the maximum amount of material that can be processed by an impactor machine.

• Impactor capacity is typically measured in tons per hour.

• It is important to match the impactor capacity to the desired output of the operation.

• Factors that can affect impactor capacity include the size and type of material being processed, the speed of the machine, and the size of the feed opening.

• For example, a hori...read more

EP2 and OG1 are two different types of grease grades with different properties.

• EP2 is a high-performance grease with extreme pressure additives that provide excellent protection against wear and tear.

• OG1 is a general-purpose grease that is suitable for a wide range of applications.

• EP2 is typically used in heavy-duty applications such as mining equipment, construction machinery, and industrial gearboxes.

• OG1 is commonly ...read more

The grade used in girth gear, bearing, and seal depends on the specific application and load requirements.

• The grade of girth gear depends on the size and load capacity of the gear.

• The grade of bearing depends on the speed and load capacity of the application.

• The grade of seal depends on the type of fluid being sealed and the operating temperature and pressure.

• Common grades for girth gears include ASTM A105, ASTM A350 L...read more

Screw compressors use screws to compress air while lobe compressors use lobes or rotors.

• Screw compressors have two interlocking screws that rotate in opposite directions to compress air.

• Lobe compressors have two or three lobes or rotors that rotate in opposite directions to compress air.

• Screw compressors are more efficient and have a higher compression ratio than lobe compressors.

• Lobe compressors are more suitable for ...read more

The type of bearing used in RALF and pump is usually a ball bearing or roller bearing.

• Ball bearings are commonly used in RALF and pump applications due to their ability to handle radial and axial loads.

• Roller bearings are also used in some applications where higher load capacity is required.

• The specific type of bearing used will depend on the size and speed of the equipment.

• Proper lubrication is important for the longe...read more

Power is the rate at which work is done or energy is transferred. A power plant converts fuel into electrical energy.

• Power is measured in watts or kilowatts.

• A power plant works by converting fuel into heat, which is then used to generate steam to turn a turbine and produce electricity.

• There are different types of power plants such as coal-fired, nuclear, hydroelectric, and renewable energy plants.

• Power factor is the ra...read more

The power triangle is a graphical representation of the relationship between real power, reactive power, and apparent power in an AC circuit.

• Real power is represented by the horizontal leg of the triangle.

• Reactive power is represented by the vertical leg of the triangle.

• Apparent power is represented by the hypotenuse of the triangle.

• The angle between the horizontal leg and the hypotenuse is the power factor angle.

• The p...read more

Phase angle is the difference in phase between two waveforms.

• Phase angle is measured in degrees or radians.

• It is used to describe the relationship between two waveforms.

• It is important in fields such as electrical engineering and physics.

• For example, in AC circuits, the phase angle between voltage and current determines the power factor.

Calculate total power consumption given a problem

• Determine the power consumption of each device

• Add up the power consumption of all devices

• Consider the time period over which power is consumed

• Account for any inefficiencies or losses in the system