In machining metals, chips break due to __________ of work material.
Toughness
Ductility
Elasticity
Work hardening
Correct Answer :
D. Work hardening
Related Questions
The hardness of a grinding wheel is specified by
Brinell hardness number
Rockwell hardness number
Vickers pyramid number
Letter of alphabet
Crater wear occurs mainly on the
Nose part, front relief face and side relief face of the cutting tool
Face of the cutting tool at a short distance from the cutting edge only
Cutting edge only
Front face only
A CNC vertical milling machine has to cut a straight slot of 10 mm width and 2mm depth by a cutter of 10 mm diameter between points (0,0) and (100,100) on the XY plane (dimensions in mm). The feed rate used for milling is 50 mm/min, milling time for the slot (in seconds) is
120
170
180
240
The cutting force in up milling __________ per tooth movement of the cutter.
Is zero
Is maximum
Decreases from maximum to zero
Increases from zero to maximum
The in-feed grinding is used to
Produce tapers
Grind shoulders and formed surfaces
Grind long, slender shafts or bars
All of these
Carbide tipped tools usually have
Negative rake angle
Positive rake angle
Any rake angle
No rake angle
The material which on machining produces chips with built up edge is
Brittle material
Tough material
Hard material
Ductile material
Side rake angle of a single point cutting tool is the angle
By which the face of the tool is inclined towards back
By which the face of the tool is inclined sideways
Between the surface of the flank immediately below the point and a plane at right angles to the centre line of the point of the tool
Between the surface of the flank immediately below the point and a line drawn from the point perpendicular to the base
Two plates of the same metal having equal thickness are to be butt welded with electric arc. When the plate thickness changes, welding is achieved by
Adjusting the current
Adjusting the duration of current
Changing the electrode size
Changing the electrode coating
With the same tool life, the maximum material per minute is removed by
Increasing the cutting speed
Decreasing the cutting speed
Increasing the depth of cut
Increasing the feed rate
In which of the following machine, the work rotates and the tool is stationary?
Vertical boring machine
Horizontal boring machine
Precision boring machine
Jig boring machine
In machining metals, chips break due to __________ of work material.
Toughness
Ductility
Elasticity
Work hardening
In lapping operation, the amount of metal removed is
0.005 to 0.01 mm
0.01 to 0.1 mm
0.05 to 0.1 mm
0.5 to 1 mm
The cutting speed of a drill depends upon the
Material of drill
Type of material to be drilled
Quality of surface finish desired
All of these
In which of the following machine, the work is usually rotated while the drill is fed into work?
Sensitive drilling machine
Radial drilling machine
Gang drilling machine
Deep hole drilling machine
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
If the helix angle of the drill is made _________ 30°, then the torque required to drive the drill at a given feed will be more.
Equal to
Less than
More than
None of these
The usual value of the point angle of a drill is
70°
100°
118°
130°
Discontinuous chips are formed during machining of
Brittle metals
Ductile metals
Hard metals
Soft metals
In order to achieve a specific surface finish in single point turning, the most important factor to be controlled is
Depth of cut
Cutting speed
Feed
Tool rake angle
What type of fusion welding process is used for welding sheet metals of all engineering metals (except Cu, Ag) in automobile and air craft industries, pipe and tubing production?
Thermit welding
Electroslag welding
Resistance welding
Submerged arc welding
Cast iron during machining produces
Continuous chips
Discontinuous chips
Continuous chips with built-up edge
None of these
A tool used to withdraw a drill from the sleeve is called
Drill remover
Drill puller
Drift
Drill drawer
A single point tool has
Rake angle
Cutting angle
Lip angle
All of these
For machining a mild steel workpiece by a high speed steel tool, the average cutting speed is
5 m/min
10 m/min
15 m/min
30 m/min
In a shaper, the length of stroke is increased by
Increasing the centre distance of bull gear and crank pin
Decreasing the centre distance of bull gear and crank pin
Increasing the length of the arm
Decreasing the length of the slot in the slotted lever
A feed gear box for a screw cutting lathe is designed on the basis of
Geometric progression
Arithmetic progression
Harmonic progression
None of these
A right hand tool on a lathe cuts most efficiently when it travels
From left to right end of the lathe bed
From right to left end of the lathe bed
With the help of a compound slide
Across the bed
The type of reamer used for reaming soft aluminium or copper, is
Straight fluted reamer
Left hand spiral fluted reamer
Right hand spiral fluted reamer
Any one of these
Hardness of steel greatly improves with
Annealing
Cyaniding
Normalizing
Tempering