Machine Tools and Machining Test on “Lathe : Thread Cutting”.
1. The threading tool is clamped in the tool post on the compound slide.
a) true
b) false
Answer: a
Clarification: 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
Answer: a
Clarification: 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
Answer: a
Clarification: 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.
4. The split is mounted in the_____ of the carriage.
a) saddle
b) apron
c) top slide
d) cross slide
Answer: b
Clarification: 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
Answer: c
Clarification: Both types of feed motion is possible in thread cutting. In order to perform these feed motions split nut’s movement is required.
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
Answer: b
Clarification: 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
Answer: d
Clarification: Saddle receives traversing motion from the lead screw of the lathe, This leadscrew has a definite pitch.
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
Answer: a
Clarification: 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