Don Bosco Tech Society Faculty and Lab Instructor Interview Questions, Process, and Tips

Heat treatment processes involve heating and cooling metals to alter their physical and mechanical properties. Machine tools are devices used to shape and cut materials.

• Heat treatment processes include annealing, quenching, tempering, and case hardening

• Machine tools include lathes, milling machines, drills, and grinders

• Examples of heat treatment processes: annealing softens metal, quenching hardens it, tempering reduce...read more

One gear making method is hobbing, where a hobbing machine uses a cutting tool called a hob to cut teeth into a blank gear.

• Hobbing is a common gear making method used in industries.

• The hobbing machine rotates the blank gear while the hob cuts the teeth into it.

• Hobbing is a precise and efficient method for producing gears with accurate tooth profiles.

• Other gear making methods include milling, shaping, and grinding.

• Indus...read more

Different types of lathe machines include engine lathe, turret lathe, and CNC lathe.

• Engine lathe: most common type, manually operated for general purpose machining

• Turret lathe: automated tooling system for high volume production

• CNC lathe: computer-controlled for precision and complex machining tasks

Taper angle in a lathe machine can be calculated using trigonometry and the formula: Taper angle = arctan((D1 - D2) / L)

• Measure the diameter at the larger end of the taper (D1)

• Measure the diameter at the smaller end of the taper (D2)

• Measure the length of the taper (L)

• Use the formula: Taper angle = arctan((D1 - D2) / L) to calculate the taper angle

IC engine stands for internal combustion engine, which generates power by burning fuel inside the engine. EC engine stands for external combustion engine, which generates power by burning fuel outside the engine.

• IC engine: Generates power by burning fuel inside the engine, examples include gasoline and diesel engines.

• EC engine: Generates power by burning fuel outside the engine, examples include steam engines and Stirl

Up milling is when the cutter rotates against the direction of feed, while down milling is when the cutter rotates in the same direction as the feed.

• In up milling, the chip thickness decreases from the start of the cut to the end, while in down milling, the chip thickness increases.

• Up milling is safer and produces a better surface finish, but down milling is more commonly used due to its lower cutting forces.

• Examples: ...read more