LATHE MACHINE MCQ 4

1) While step turning, it is preferred to turn first

small diameter step

large diameter step

either ‘a’ or ‘b’

neither ‘a’ nor ‘b’

Correct Answer- (D)

2) Which one of the following types of chips is found while turning cast iron?

I-shaped chips

Spiral chips

Long curly chips

Segmental chips.

Correct Answer- (B)

3) As the diameter of the workpiece decreases, the spindle speed (for the same cutting speed)

increases

decreases

remains the same

none of the above

Correct Answer- (A)

4) The difference in measurement between the machined and un-machined diameter is equal to the

depth of cut

1/2 x depth of cut

2 x depth of cut

none of the above

Correct Answer- (C)

5) Centre drilling should be done at

higher rpm with a slower feed

higher rpm with a higher feed

slower rpm with a higher feed

slower rpm with a slower feed

Correct Answer- (A)

6) Which among the following is the cause for incorrect pitch of thread during thread cutting with single point tool?

Incorrect selection of change gears

Lead screw worn out

Half nut worn out

Any one of the above

Correct Answer- (D)

7) Which one of the following is the reason for torn threads while thread cutting on lathe?

Blunt tool

Heavy depth of cut

Insufficient side clearance

Any one of the above

Correct Answer- (C)

8) For setting of tool for threading, if is aligned with the work by using

try square

thread plug gauge

template

centre gauge

Correct Answer- (C)

9) Which among the following statements in respect of threads/ thread cutting is NOT correct?

Threading tools are checked for accuracy for the 600 angle by using a centre gauge

M 10 x 1.25 is a fine pitch thread

M 10 is a coarse pitch thread

Same tool is used for cutting external and internal threads

Correct Answer- (D)

10) While cutting internal threads on lathe with single point tool, the spindle speed should be

less than that for the plain turning operations

more than that for the plain turning operation

equal to that for plain turning operation

None of the above

Correct Answer- (D)

11) Which one of the following statements in respect of thread cutting is NOT correct?

Inserted tool bits are more advantageous while cutting internal threads

Before cutting internal threads, the hole should be chamfered

When internal thread cutting is done in a blind hole, a recess should be provided

When cutting internal threads, the core diameter may be equal to the size of external threads

Correct Answer- (A)

12) Which among the following in respect of thread cutting is NOT correct?

The teeth of the driver and driven are based on the pitch of thread to be cut and the pitch of thread on lead screw

The threads can be cut on a lathe by using simple gear train arrangement only

The 63 teeth gear ¡s used as a driver for cutting British threads on a lathe having metric lead screw

The 127 teeth gear is used as driven gear for cutting metric threads on a lathe having lead screw in TPI

Correct Answer- (C)

13) Which one of the following statements in respect of eccentric turning is correct?

Eccentric shaft can be turned by holding it in a three-jaw chuck

Higher speed is chosen for eccentric turning

In an eccentric shaft, the centres of the individual diameters are displaced

It is preferred to give more depth of cut in the beginning while turning an eccentric shaft

Correct Answer- (B)

14) Which one of the following statements in respect of thread chasing dial is NOT correct?

Worm gear of chasing dial engages with the lead screw while thread chasing

Thread chasing dial is an additional part of the lathe carriage

Thread chasing dial is used to catch the thread when threading on lathe

Thread chasing dial stops rotating when the half nut lever is engaged

Correct Answer- (D)

15) If the pitch to be cut is 2.5 mm and the lathe has 5 mm pitch lead screw, the thread chasing dial has 8 divisions and a 16 teeth worm wheel fitted on it, the engagement of half nut should be

only at one particular position

only at numbered or un-numbered division

at opposite position

anywhere

Correct Answer- (A)

16) Which among the following statements is correct?

During turning, after giving one depth of cut, the diameter is reduced equal to double the depth

Carbide tipped tool can withstand shock load

When turning bigger diameter job, the rpm is proportionally increased

When turning smaller diameter job,the rpm is proportionally decreased

Correct Answer- (B)

17) A 24-teeth gear is fixed at stud as driver gear. After completion of first start and before starting of second start, the driver gear should be turned

18 teeth

12 teeth

6 teeth

24 teeth

Correct Answer- (B)

18)A simple gear train is to be used to cut a thread with a certain pitch. A driver gear with 3 teeth more than that of the calculated value is mounted due to the non-availability of the required gear from the set. The thread that is cut will have the pitch

Less than that required throughout the length

Equal to that required throughout the length

More than that required throughout the length

More for a certain length and then less for the remaining length

Correct Answer- (D)

19) Power feed is not possible in compound slide method of taper turning. Which one of the following defects can be noticeable on the tapered workpiece due to the above reason?

Taper angle less than set

Chatter

Poor surface finish

Taper angle more than set

Correct Answer- (D)

20) To get a fine even surface on a workpiece by facing operation on lathe, it is necessary to have

low cutting speed, fine feed and heavy depth of cut

low cutting speed, fine feed and light depth of cut

high cutting speed, fine feed and light depth of cut

high cutting speed, fine feed and heavy depth of cut

Correct Answer- (A)