Machine Tools Questions and Answers – Lathe : Thread Cutting

This set of Machine Tools and Machining Test focuses on “Lathe : Thread Cutting”.

1. The threading tool is clamped in the tool post on the compound slide.
a) true
b) false
View Answer

Answer: a
Explanation: It can be easily understood by looking at the definition of the threading. The tool post holds the tool or tools meant for the operation to be performed on the work.

2. The lead screw obtains_____ motion from the working spindle.
a) rotary
b) transmitting
c) both rotary and transmitting
d) none of the mentioned
View Answer

Answer: a
Explanation: The lead screw obtains rotary motion from the working spindle. The lead screw drives the tool post axially against the workpiece to produce a helical groove.

3. The _____ motion is converted into_____ motion of the tool slide
in thread cutting.
a) rotary, feed
b) feed, rotary
c) transmitting, longitudinal
d) none of the mentioned
View Answer

Answer: a
Explanation: The rotary motion is converted into feed motion. The ledscrew has a trapezoidal thread and obtains this rotary motion which converts into feed motion by split.
advertisement
advertisement

4. The split is mounted in the_____ of the carriage.
a) saddle
b) apron
c) top slide
d) cross slide
View Answer

Answer: b
Explanation: It can be easily seen from the construction of the carriage. The apron is fastened to the saddle and hangs over the front of the bed.

5. In thread cutting, which type of feed motion is possible?
a) engaging
b) disengaging
c) either engaging or disengaging
d) none of the mentioned
View Answer

Answer: c
Explanation: Both types of feed motion is possible in thread cutting. In order to perform these feed motions split nut’s movement is required.
Note: Join free Sanfoundry classes at Telegram or Youtube

6. In thread cutting, the _____ feeds should be equal to the pitch of the thread, which is to be cut per revolution of the work piece.
a) cross feed
b) longitudinal feed
c) angular feed
d) none of the mentioned
View Answer

Answer: b
Explanation: This is the definition of the longitudinal feeds. Again here the feed is the distance the tool advances for each revolution of work.

7. In thread cutting, which of the following receives traversing motion from the lead screw of the lathe?
a) apron
b) top slide
c) cross slide
d) none of the mentioned
View Answer

Answer: d
Explanation: Saddle receives traversing motion from the lead screw of the lathe, This leadscrew has a definite pitch.
advertisement

8. In thread cutting, definite ratio is calculated between the_____ feed and rotation of the_____ spindle.
a) longitudinal, headstock
b) cross, headstock
c) cross, tailstock
d) longitudinal, tailstock
View Answer

Answer: a
Explanation: The definite ratio is calculated between the longitudinal type of feed and the rotation of the headstock spindle. This ratio should be found out so that the relative speeds of rotation of the work and the leadscrew will result in the cutting of a screw of the desired pitch.

9. Which of the following is not true for thread cutting?
a) tool post is driven by lead screw axially against the work piece
b) the lead screw has a trapezoidal thread
c) the relative type of speeds of rotation of the work and the lead screw can result in the cutting of a screw of the desired pitch
d) none of the mentioned
View Answer

Answer: d
Explanation: All the sentences are true. These all mentioned sentences are the related with the working of the thread cutting which can be carried on a lathe to obtain standard forms and properties of screw threads by using appropriate tools.
advertisement

10. In thread chasing dial, the half nut is_____ when any live on the dial coincides with a reference live already set.
a) opened
b) closed
c) partially opened and partially closed
d) none of the mentioned
View Answer

Answer: b
Explanation: At this condition, the half nut is closed to avoid collision. Thread chasing dial is a special attachment used in cutting threads.

11. In thread chasing dial, half nut is closed when any numbered live coincides with reference live for_____ thread.
a) even
b) odd
c) can’t say anything
d) none of the mentioned
View Answer

Answer: b
Explanation: In thread chasing dial, half nut is closed when any numbered live coincides with reference live for odd thread. The dial indicates when to close the split nut.

12. The chasing dial is mounted on the right end of the _____
a) tool post
b) apron
c) head stock
d) none of the mentioned
View Answer

Answer: b
Explanation: The chasing dial is mounted on the right end of the apron. This chasing dial is generally used to pick up the thread.

13. In chasing dial, dial rotate as long as the half nut is_____
a) engaged
b) not engaged
c) either engaged or not engaged
d) none of the mentioned
View Answer

Answer: b
Explanation: In chasing dial, dial rotate as long as the half nut is not engaged. Dial stops when the half nut is engaged.

14. An odd thread is one, whose pitch is an exact multiple of the pitch of the lead screw.
a) true
b) false
View Answer

Answer: b
Explanation: This is false. An even thread is one, whose pitch is an exact multiple of the pitch of the lead screw.

15. For feed motion, split nut has to be_____
a) always closed
b) always opened
c) either opened or closed (depend upon motion)
d) none of the mentioned
View Answer

Answer: c
Explanation: Split nut may be open or close depends upon the situations. This is done in order to engage or disengage the feed motion.

Sanfoundry Global Education & Learning Series – Machine Tools and Machining.
To practice all areas of Machine Tools and Machining for various tests, here is complete set of 1000+ Multiple Choice Questions and Answers.

If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]

advertisement
advertisement
Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & discussions at Telegram SanfoundryClasses.