(SEM V) THEORY EXAMINATION 2017-18 MANUFACTURING SCIENCE AND TECHNOLOGY-II

Manufacturing Science and Technology-II (NME-503)

Section-Wise Important Questions & Study Notes

SECTION–A

(Attempt all | 2 × 10 = 20)
This section checks basic concepts, definitions, and differences.
Write short, crisp answers (2–3 lines).

Arc Blow
Arc blow is the deflection of welding arc due to magnetic fields, causing uneven weld bead and defects.

Boring, Reaming & Broaching
Boring enlarges an existing hole, reaming improves hole accuracy and finish, broaching removes material using a multi-tooth tool in one pass.

Continuous Chip with Built-Up Edge (BUE)
Occurs during machining of ductile materials at low cutting speeds when material adheres to tool edge.

End Milling vs Face Milling
End milling cuts using the end and sides of cutter; face milling cuts mainly with the face of the cutter.

Grinding Wheel Wear Types
Attritious wear, fracture wear, and bond failure.

Dressing vs Truing
Dressing sharpens the wheel; truing restores wheel shape and concentricity.

Centerless Grinding
Grinding process without centers where workpiece is supported by a work rest and regulated wheel.

HAZ (Heat Affected Zone)
Portion of base metal near weld whose properties change due to heat.

TIG vs MIG (Any Three Differences)
Electrode type, shielding gas, metal deposition, applications.

Welding Defects (Names Only)
Porosity, cracks, slag inclusion, undercut, lack of fusion, distortion.

SECTION–B

(Attempt any THREE | 10 × 3 = 30)

Theory + numericals, write answers with headings and steps.

1. Grinding Wheel Specification

Explain:                                                       Abrasive type

Grain size                                                    Grade

Bond                                                           Structure
Use standard designation format.

2. Soldering and Brazing

Explain:                                                       Temperature range

Filler material                                              Flux

Applications                                               Differentiate between soldering & brazing.

3. Arc Welding & Types of Arc

Explain arc welding principle and types of arc:

Stable arc                                                   Unstable arc

Short arc                                                     Long arc

4. Orthogonal Cutting Numerical

Using given rake angle, chip ratio, friction coefficient:      Draw Merchant force circle

Calculate cutting force, thrust force, normal & frictional forces
Write formula → substitution → answer with units.

5. Shaper Machine

Explain working principle and mechanism.
Differentiate shaper vs planner (job size, tool movement, applications).

SECTION–C

(Attempt any ONE | 10 × 1 = 10)

3(a) Merchant’s Force Circle Diagram

Explain forces involved and derive Merchant’s shear angle relationship:

ϕ=45∘+α2−β2\phi = 45^\circ + \frac{\alpha}{2} - \frac{\beta}{2}ϕ=45∘+2α​−2β​

OR

3(b) Cutting Fluids & Tool Wear

Explain:                                           Functions of cutting fluids

Types of cutting fluids                    Crater wear & flank wear with neat sketches