Tool Life Objective Type Questions and Answers

21 The cutting velocity in m/sec, for turning a work piece of diameter 100 mm at the spindle speed of 480 rpm is

A 2.51

B 151

C 1.26

D 48

View Answer

Answer: 2.51

22 Which of the following tool materials have cobalt as a constituent element?

1. Tungsten carbide 2. CBN 3. Stellite 4. UCON

Select the correct answer using the codes given below

A 1 & 2

B 1 & 3

C 1 & 4

D 2 & 3

View Answer

Answer:1 & 3

23 The approximately variation of the tool life exponent ‘n’ of cemented carbide tools is

A 0.20 to 0.48

B 0.48 to 0.70

C 0.03 to 0.08

D None of the above

View Answer

Answer: 0.20 to 0.48

24 The coating materials for coated carbide tools, include

A TiC and TiN

B TiC and NaCN

C TiN and NaCN

D TiC, TiN and NaCN

View Answer

Answer: TiC and TiN

25 Which one of the following grinding wheels (with grade, grit and bond) is suitable for cutter grinding?

A T 60 resinoid

B T 320 resinoid

C K 60 vitrified

D None of the above

View Answer

Answer: K 60 vitrified

26 Using the Taylor equation VT^n=c, calculate the percentage increase in tool life when the cutting speed is reduced is reduced by 50% (n=0.5 and c=400)

A 300%

B 400%

C 100%

D 50%

View Answer

Answer: 400%

27 Consider the following actions:

1. Mechanical abrasion

2. Diffusion

3. Plastic deformation

4. Oxidation

Which of the above are the causes of tool wear?

A 2 & 3

B 1 & 2

C 1, 2 & 4

D 1 & 3

View Answer

Answer: 1, 2 & 4

28 Tool material not suited to resistance welding is

A Stellite

B Masonite

C High speed steel

D Aluminium oxide

View Answer

Answer: Stellite

29 Consider the following statements: Chipping of a cutting tool is due to

1. Tool material being too brittle

2. Hot hardness of the tool material

3. High positive rake angle of the tool

Which of these statements are correct?

A 1, 2 & 3

B 1 & 3

C 2 & 3

D 1 & 2

View Answer

Answer: 1 & 3

30 A milling cutter of 70 mm diameter with 12 teeth is operating at a cutting speed of 22 m/min and a feed of 0.05 mm/tooth. The feed rate per minute is

A 60 mm/min

B 6 mm/min

C 110 mm/min

D 35 mm/min

View Answer

Answer: 60 mm/min

31 Tool life is most affected by machine.......

A Feed and depth

B Microstracture of material being cut

C Cutting speed

D Tool geometry

View Answer

Answer: Cutting speed

32 Tool life is said to be over if.......

A Overheating and funning due to friction start

B Sudden increase in power and cutting force with chattering take place

C A poor surface finish is obtained

D All of the above

View Answer

Answer: All of the above

33 Sanding is a process of removing metal surfaces or wood fibres by.........

A Cutting

B Planning

C Sawing

D Filling

View Answer

Answer: Cutting

34 Sanding belts are made of cloth, coated with various grades of......

A Aluminium oxide

B Diamond

C Gravel

D None of the above

View Answer

Answer: Aluminium oxide

35 The materials are added to cutting tools to increase their properties. Match the following

1. Tungsten a. Hardness

2. Carbon b. Hot hardness

3. Vanadium c. Wear resistance

The correct order is

A 1-b, 2-a, 3-c

B 1-c, 2-a, 3-b

C 1-b, 2-c, 3-a

D 1-a, 2-b, 3-c

View Answer

Answer: 1-b, 2-a, 3-c

36 Which of the following is not a constituent of High speed steel?

A Ni

B Cr

C W

D None of the above is correct.

View Answer

Answer: Ni

37 Match list-I (Cutting tool material) with List-II (Typical value of tool life exponent ‘n’ in the Taylor’s equation V.T^n=C) and select the correct answer using the codes given below the lists:

List I List II

a. HSS 1. 0.18

b. Cast alloy 2. 0.12

c. Ceramic 3. 0.25

d. Sintered carbide 4. 0.5

A a-1, b-2, c-3, d-4

B a-2, b-1, c-3, d-4

C a-2, b-1, c-4, d-3

D a-1, b-2, c-4, d-3

View Answer