In machining metals, surface roughness is due to
Feed marks or ridges left by the cutting tool
Fragment of built-up edge on the machined surface
Cutting tool vibrations
All of these
Correct Answer :
D. All of these
Related Questions
The method of grinding used to produce internal cylindrical holes and tapers, is
Internal cylindrical grinding
Form grinding
External cylindrical grinding
Surface grinding
In ECM, the material removal is due to
Corrosion
Erosion
Fusion
Ion displacement
A diamond locating pin is used in jigs and fixtures because
Diamond is very hard and wear resistant
It occupies very little space
It helps in assembly with tolerance on centre distance
It has a long life
Which of the following statement is correct in regard to centreless grinding?
The workpiece is supported throughout its entire length as grinding takes place.
It is a continuous process and adopted for production work.
It requires no holding device for the work.
All of the above
Which of the following operation is first performed?
Spot facing
Boring
Tapping
Drilling
The factor responsible for the formation of continuous chips with built up edge is
Low cutting speed and large rake angle
Low cutting speed and small rake angle
High cutting speed and large rake angle
High cutting speed and small rake angle
The cutting angle of a flat drill varies from
3° to 8°
20° to 30°
60° to 90°
90° to 120°
A shaft has a dimension, φ9 +0.025⁺⁰⁰⁰⁹, the respective values of fundamental deviation and tolerance are
- 0.025, ±0.008
- 0.025, 0.016
- 0.009, ± 0.008
- 0.009, 0.016
A coarse grained grinding wheel is used to grind
Hard and brittle materials
Soft and ductile materials
Hard and ductile materials
Soft and brittle materials
In ultrasonic machining, the metal is removed by
Using abrasive slurry between the tool and work
Direct contact of tool with the work
Maintaining an electrolyte between the work and tool in a very small gap between the two
Erosion caused by rapidly recurring spark discharges between the tool and work
Which of the following statement is wrong?
The diamond is the hardest tool material and can run at cutting speeds about 50 times that of high speed steel tool.
The ceramic tools can be used at cutting speeds 40 times that of high speed steel tools.
The cemented carbide tools can be used at cutting speeds 10 times that of high speed steel tools.
The ceramic tools can withstand temperature upto 600°C only.
The rear teeth of a broach
Perform burnishing operation
Remove minimum metal
Remove maximum metal
Remove no metal
The grade of grinding wheel depends upon
Hardness of the material being ground
Speed of wheel and work
Condition of grinding machine
All of these
Which of the following statement is correct for orthogonal cutting system?
The cutting edge of the tool is perpendicular to the direction of tool travel.
The cutting edge clears the width of the workpiece on either ends.
The chip flows over the tool face and the direction of the chip flow velocity is normal to the cutting edge.
All of the above
A grinding wheel is said to be of _________ if the abrasive grains can be easily dislodged.
Soft grade
Medium grade
Hard grade
None of these
A dense structure of a grinding wheel is used for
Hard materials
Brittle materials
Finishing cuts
All of these
In drilling Bakelite and fibrous plastics, the point angle of a drill is
90°
118°
135°
150°
Which one of the following is a solid state joining process?
Gas tungsten arc welding
Resistance spot welding
Friction welding
Submerged arc welding
The cutting force in punching and blanking operations mainly depends on
The modulus of elasticity of metal
The shear strength of metal
The bulk modulus of metal
The yield strength of metal
The chamfering is an essential operation after
Knurling
Rough turning
Boring
Thread cutting
Which of the following statement is wrong?
The larger side rake angle produces chipping.
The smaller rake angle produces excessive wear and deformation in tool.
The side cutting edge angle (less than 15°) increases tool life.
The increase in nose radius decreases tool life.
Ultrasonic machining is best suited for
Tool steels
Sintered carbides
Glass
All of these
The percentage of carbon in gray cast iron is in the range of
0.25 to 0.75 percent
1.25 to 1.75 percent
3 to 4 percent
8 to 10 percent
Hardness of steel greatly improves with
Annealing
Cyaniding
Normalizing
Tempering
In down milling, the thickness of chip is
Minimum at the beginning of the cut and maximum at the end of the cut
Maximum at the beginning of the cut and minimum at the end of the cut
Uniform throughout the cut
None of these
When the shear angle is small
Path of shear is short and chip is thin
Path of shear is large and chip is thick
Path of shear is short and chip is thick
Path of shear is large and chip is thin
The type of reamer used for reaming operation in a blind hole, is
Straight fluted reamer
Left hand spiral fluted reamer
Right hand spiral fluted reamer
Any one of these
In drilling operation, the metal is removed by
Shearing
Extrusion
Shearing and extrusion
Shearing and compression
The obtuse angle, included between the chisel edge and the lip as viewed from the end of a drill, is called
Helix or rake angle
Point angle
Chisel edge angle
Lip clearance angle
The carbide tools operating at very low cutting speeds (below 30 m/min)
Reduces tool life
Increases tool life
Have no effect on tool life
Spoils the work piece