Question Set 9 – Mechanical Engineering

# Question Set 9

Question No. 1

What are the uses of Graphite electrode in various fields?

Graphite electrode is used in EDM and in battery cells. It is also used in electric arc furnaces to melt the steel.

Question No. 2

Difference between TIG & MIG welding

TIG – Tungsten inert gas welding-non consumable electrode

MIG – Metal inert gas welding-uses consumable electrode

Question No. 3

Do you know epicyclic gear box? What is the practical application of epicyclic gear box?

Epicyclic gear box consists of sun gear planetary gears and an annular called ring gear. Different speed ratios are obtained by locking any one gear. If you lock any two gears, direct gear will be obtained. Mostly used in over drives.

Wrist watch is a practical application of epicyclic gear box

Question No. 4

What is the purpose of scrapper ring?

Scrap the excess lube oil from the cylinder walls. There by preventing oil from entering combustion zone.

Question No. 5

What is the difference between S.S to EN8?

SS- Stainless steel

En- Medium carbon steel

SS is Non Magnetic material & EN8 is Magnetic material

SS is Corrosion resistant & EN8 is Magnetic material

Question No. 6

How to calculate the speed of conveyor in Meter per Minute

Measure the diameter of the rollers around which the conveyor belt is wrapped.

Multiply the diameter of the roller by pi (3.14159). This calculation will yield the circumference of the rollers. Every time the roller spins one revolution, the conveyor will be moved a linear distance equivalent to the circumference of the roller. Pi is a dimensionless factor, meaning it does not matter whether inches, centimeters or any other units of measurement are used. Measure the revolutions per minute (RPM) of the rollers. Count how many full revolutions (rotations) are made by the roller in one minute. Multiply the RPM by the circumference of the roller. This calculation will give the linear distance traversed by a point on the conveyor belt in one minute.

Question No. 7

What is the use of a PULLEY?

Transmission of power (force) in rotary form

Question No. 8

Why does cycle rim don’t bend even in heavy loads?

Because of rubber tires. The load is distributed and its effect reduces i.e. tires absorbs heavy load and shocks with the support of steel rim. The rim has many spokes. The spokes distribute the load equally and the rubber tires absorb more than half of the load.

Question No. 9

What is caustic embrittlement?

It is the actual physical change in metal that makes it extremely brittle and filled with minute cracks. It occurs particularly in the seams of riveted joints and around the rivet holes.

Question No. 10

What type of section of same area will resist maximum bending moment, I section, rectangular or circular section?