Machine Tools and Machining Questions & Answers for campus interviews on “Classification of Drilling Machine : According to Specific Use”.
1. According to specific use, drill can be classified as______
a) center drill
b) step drill
c) both center drill and step drill
d) none of the mentioned
Answer: c
Clarification: Both are the examples of specific use drill. These special purpose drilling machines are intended for drilling multiple holes at a single setting.
2. Subland drill is type of drill according to______
a) l/d ratio
b) shank type
c) specific use
d) none of the mentioned
Answer: c
Clarification: Subland drill is the example of special purpose drilling machine. Apart from this, turret, micro drill press and muliple spindle drilling machines are also an example of specific purpose drilling machine.
3. Which of the following drill is very short drill?
a) center drill
b) subland drill
c) step drill
d) none of the mentioned
Answer: a
Clarification: Center drill is very short drill. Subland drill and step drill are large as compare to center drill.
4. Which of the following is not true for center drill?
a) the hole is used to support the center
b) it is the type of drill according to specific use
c) one taper has to be made here
d) none of the mentioned
Answer: d
Clarification: All the mentioned sentences are true. It has a taper and also it is a specific purpose drill machine. It is short drill.
5. In center drill, center has to be mounted on______
a) headstock
b) tailstock
c) headstock or tailstock
d) none of the mentioned
Answer: c
Clarification: The center can be mounted on either headstock or tailstock. Headstock and tailstock both are mounted on the bed.
6. In which of the following, l/d ratio is very long?
a) half round drill
b) gun drill
c) both half round drill and gun drill
d) none of the mentioned
Answer: c
Clarification: Here l=length and d=diameter. In both half round drill and gun drill this ratio is very long as they have large value of length as compare to diameter.
7. How many cutting edges are there in half round drill and gun drill?
a) one
b) two
c) may be one or two
d) none of the mentioned
Answer: a
Clarification: One edge is there in these both half round drill and gun drill. In these both drills, diameter is less as compare to length.
8. How many flutes are there in half round drill and gun drill?
a) one
b) two
c) may be one or two
d) none of the mentioned
Answer: c
Clarification: One or two flutes are there in these both machines. These both machines are specific purpose machines used for a specific purpose.
9. In half round drill, base is weak.
a) true
b) false
Answer: b
Clarification: This is false. The base is very strong in half round drill.
10. Which of the following is a pipe like cutting tool?
a) center drill
b) half round drill
c) gun drill
d) none of the mentioned
Answer: d
Clarification: Trepanning tool has this structure. It structure looks like a pipe.
11. Trepanning is feasible for hard materials.
a) true
b) false
Answer: b
Clarification: This is false. Trepanning is not feasible for hard materials. It is feasible for soft material.
Machine Tools and Machining for campus interviews,