1) Chip breakers are meant to break continuous long chips. Which one of the following types of chip breakers is found on a throwaway insert with the holder?
The piece of sheet metal clamped to the holder in the path of the coil.
A step is ground on the throwaway insert along the cutting edge.
A carbide bit is screwed and held on the top face of the bit.
A small groove ground at the cutting edge.
2) The tip of a cemented carbide tool is joined on the shank by
welding
brazing
soldering
clamping with a screw
3) To enable a nut to fit properly on a bolt of square threads, the width of the internal square threading tool should be provided on the tool made of ..............
slightly more than the half pitch
slightly less than the half pitch
equal to the half pitch
equal to the pitch
4) Which one of the following materials for lathe cutting tools can be forged to any desired shape?
High carbon steel
Stellite
High-speed steel
Tungsten carbide
5) When rough turning a workpiece with a carbide tool long curly chips are formed. Which one of the following is the right way of getting rid of this kind of chip?
Change the rake angle
Provide a chip breaker on the tool
Use a metal hook and pull away from the chips
Stop the power feed at intervals so that the chip breaks
6) A brass shaft is to be turned to a surface roughness Ra = 0.8, with high cutting speed. Which one of the following cutting tool materials is most suitable? center height on the lathe?
Cemented carbide
High-speed steel
High carbon steel
Low alloy steel
7) Which one of the following statements is true with reference to the tool life?
The time between starting and finishing a job.
Total time for turning work including regrinding of the tool.
The time between two successive regrinds.
The time between starting of metal cutting and tool wear out.
8) A carbide tipped tool with blue marking is used on a lathe. Which one of the following materials can be machined with this tool?
Grey cast iron
Steel
Brass
Plastic
9) Hand chasers are used for
rectifying threads cut on steel rods which are distorted
quick production of threads
cutting threads on soft metal directly
rectifying crest and root of threads formed by single point tool
10) The included angle of the countersinking portion of a center drill of type ‘B’ used for protecting the center hole is
75°
90°
100°
120°
11) Which one of the following is the correct position of threading tool to cut V-thread?
Exactly at center height of the workpiece with the tool axis perpendicular to the workpiece axis.
Exactly at center height of the workpiece with tool axis at 60° to the workpiece axis.
Exactly at centre height of the workpiece with tool axis at 45° to the workpiece axis.
Exactly at centre height of the workpiece with tool axis at 45° to the workpiece axis
12) Which among the following statements is suitable to get a better finish by turning?
Increase the speed and feed
Reduce the speed and feed
Increase the speed and reduce the feed
Increase the feed and reduce the speed
13) For plain turning a 60 mm diameter workpiece using HSS tool with a recommended cutting speed of 30 metre / min., the rpm should be
80 rpm
159 rpm
192 rpm
318 rpm
14) Which among the following factors governs the selection of feed when turning a workpiece?
Tool geometry
Surface finish required
Type of coolant required
All of the above
15) Which one of the following shoulders is used on components to be threaded?
Undercut shoulder
Square shoulder
Beveled shoulder
Radius shoulder
16) Which range of cutting speed is set for turning a mild steel using a HSS tool?
15—20m/min
35—50m/min
50—80m /mm
70—100m/mm
17) Which one of the following combination of movements is used to turn a ball on a centre lathe with single point tool ?
Carriage and compound slides are used
Cross slide and compound slides are used
Carriage and cross slide are used
Compound slide and apron are used
18) State the direction of rotation of job and lead screw while cutting left hand thread viewing from tailstock end. (CW = clockwise; ACW = anticlockwise).
Both the job and lead screw rotate CW
Both the job and lead screw rotate ACW
Job rotates CW and lead screw rotates ACW
Job rotates ACW and lead screw rotates CW
19) Counter boring is done for
deburring hole ends
enlarging holes to accurate size
finishing cored holes
accommodating socket head screws
20) Fine facing is done by feeding the tool
from the centre to the periphery of the job
from the periphery to the centre of the job
either ‘a’ or ‘b’
neither ‘a’ nor ‘b’
from the centre to the periphery of the job
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