In gear hobbing
Only hob rotates
Only gear blank rotates
Both hob and gear blank rotates
Neither hob nor gear blank rotates
Correct Answer :
C. Both hob and gear blank rotates
Related Questions
In a shaper, the metal is removed during
Forward stroke
Return stroke
Both the forward and return strokes
Neither the forward nor the return stroke
Ultrasonic machining is best suited for
Tool steels
Sintered carbides
Glass
All of these
In reaming process
Metal removal rate is high
High surface finish is obtained
High form accuracy is obtained
High dimensional accuracy is obtained
The tool may fail due to
Cracking at the cutting edge due to thermal stresses
Chipping of the cutting edge
Plastic deformation of the cutting edge
All of these
The mechanism of material removal in EDM process is
Melting and Evaporation
Melting and Corrosion
Erosion and Cavitations
Cavitations and Evaporation
A twist drill is a
Side cutting tool
Front cutting tool
End cutting tool
None of these
Which of the following statement is correct about nose radius?
It improves tool life
It improves the surface finish
Both (A) and (B)
None of these
A grinding wheel becomes glazed (i.e. cutting edge takes a glasslike appearance) due to
Wear of bond
Breaking of abrasive grains
Wear of abrasive grains
Cracks on grinding wheel
The cutting speed for counter-boring should be _________ that of drilling operation.
Equal to
Less than
Greater than
None of these
The maximum possible draft in cold rolling of sheet increases with the
Increase in coefficient of friction
Decrease in coefficient of friction
Decrease in roll radius
Decrease in roll velocity
The aluminium oxide abrasive is chiefly used for grinding
High speed steel
Carbon steel
Wrought iron
All of these
When two main plates are kept in alignment butting each other and riveted with cover plate on both sides of the main plates with two rows of rivets in each main plate, the joint is known as _______ double cover butt joint.
Single riveted
Double riveted
Both (A) and (B)
None of these
Two streams of liquid metal which are not hot enough to fuse properly result into a casting defect known as
Cold shut
Swell
Sand wash
Scab
For generating a Coons surface we require
A set of grid points on the surface
A set of grid control points
Four bounding curves defining the surface
Two bounding curves and a set of grid control points
Glazing in grinding wheels can be decreased by
Using a harder wheel or by increasing the wheel speed
Using a softer wheel or by decreasing the wheel speed
Using a harder wheel or by decreasing the wheel speed
Using a softer wheel or by increasing the wheel speed
In ECM, the material removal is due to
Corrosion
Erosion
Fusion
Ion displacement
The cutting fluid mostly used for machining alloy steels is
Water
Soluble oil
Dry
Sulphurised mineral oil
The work or surface speed for cylindrical grinding varies from
5 to 10 m/min
10 to 20 m/min
20 to 30 m/min
40 to 60 m/min
In a gating system, the ratio 1: 2: 4 represents
Sprue base area: runner area: ingate area
Pouring basin area: ingate area: runner area
Sprue base area: ingate area: casting area
Runner area: ingate area: casting area
Green sand mould indicates that
Polymeric mould has been cured
Mould has been totally dried
Mould is green in colour
Mould contains moisture
The lead screw of a lathe has _________ threads.
Single start
Double start
Multi-start
Any one of these
In an orthogonal cutting, the depth of cut is halved and the feed rate is double. If the chip thickness ratio is unaffected with the changed cutting conditions, the actual chip thickness will be
Doubled
Halved
Quadrupled
Unchanged
High speed steel tools retain their hardness upto a temperature of
250°C
350°C
500°C
900°C
Carbide tipped tools usually have
Negative rake angle
Positive rake angle
Any rake angle
No rake angle
The method of grinding used to produce a straight or tapered surface on a workpiece, is
Internal cylindrical grinding
Form grinding
External cylindrical grinding
Surface grinding
The ratio between two consecutive spindle speeds for a six-speed drilling machine using drills of diameter 6.25 to 25 mm size and at a cutting velocity of 18 m/min is
1.02
1.32
1.66
1.82
In a plain milling cutter, the chip space between the back of one tooth and the face of the next tooth is called
Face
Fillet
Gash
Land
In orthogonal turning of a low carbon steel bar of diameter 150 mm with uncoated carbide tool, the cutting velocity is 90 m/min. The feed is 0.24 mm/rev and the depth of cut is 2mm. The chip thickness obtained is 0.48 mm. If the orthogonal rake angle is zero and the principle cutting edge angle is 90⁰, the shear angle in degree is
20.56
26.56
30.56
36.56
The usual value of the point angle of a drill is
70°
100°
118°
130°
For machining a mild steel workpiece using carbide tool, the maximum material will be removed at a temperature of
50°C
100°C
175°C
275°C