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
Correct Answer :
B. Less than
Related Questions
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
Jigs are used
For holding and guiding the tool in drilling, reaming or tapping operations
For holding the work in milling, grinding, planing or turning operations
To check the accuracy of workpiece
None of the above
When the end of a tap is tapered for about three or four threads, it is known as a
Taper tap
Bottoming tap
Second tap
None of these
In transverse grinding
The work is reciprocated as the wheel feeds to produce cylinders longer than the width of wheel face
The work rotates in a fixed position as the wheel feeds to produce cylinders equal to or shorter than the width of wheel face
The work is reciprocated as the wheel feeds to produce cylinders shorter than the width of wheel face
The work rotates in a fixed position as the wheel feeds to produce cylinders longer than the width of wheel face
Soft materials can not be economically ground due to
High temperature involved
Frequent wheel clogging
Rapid wheel wear
Low work piece stiffness
In DC arc welding, if leads are arranged in work as Negative pole of the welding arc and electrode as Positive pole of the welding arc, the arrangement is known as
Fusion
Reverse polarity
Forward welding
Direct polarity
In metal cutting, use of low feeds and high cutting speeds is desired when the objective is
High metal removal rate
Dry machining
Use of soft cutting tool
Surface finish
High speed steel tools retain their hardness upto a temperature of
250°C
350°C
500°C
900°C
The process of changing the shape of grinding wheel as it becomes worn due to breaking away of the abrasive and bond, is called
Truing
Dressing
Facing
Clearing
In drilling brass, a drill with
Zero helix angle is used
Low helix angle is used
High helix angle is used
Any helix angle can be used
Buffing wheels are made of
Softer metals
Cotton fabric
Carbon
Graphite
What is the type of welding defect is caused due to stresses on heating and cooling called?
Incomplete penetration
Shrinkage void
Slag Entrapment (Inclusions)
Incomplete fusion
A broach has
Roughing teeth
Semi-finishing teeth
Finishing teeth
All of these
EDM machining is applied for
Shaping carbide dies and punches having complicated profiles
Making large number of small holes in sieves and fuel nozzles
Embossing and engraving on harder materials
All of these
The object of caulking in a riveted joint is to make the joint
Free from corrosion
Stronger in tension
Free from stresses
Leak-proof
The lip angle of a single point tool is usually
20° to 40°
40° to 60°
60° to 80°
None of these
The tailstock set over required to turn a taper on the entire length of a workpiece having diameters D and d is
(D - d)/2L
(D - d)/L
(D - d)/2
D - d
As the cutting speed increases, the tool cutting forces
Remain constant
Increases
Decreases
First increases and then decreases
The snag grinding is done
To produce good surface finish and high degree of accuracy
To remove considerable amount of metal without regard to accuracy of the finished surface
To grind exterior cylindrical surfaces
Any one of the above
The operation of machining several surfaces of a workpiece simultaneously is called
Profile milling
Gang milling
Saw milling
Helical milling
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
The average cutting speed for turning mild steel with a high speed steel tool is
15 to 19 m/min
25 to 31 m/min
60 to 90 m/min
90 to 120 m/min
In a metal arc welding process, a gas metal arc welding with magnetized flux is used and can be done in all the positions i.e. flat position, vertical position or inclined position.
Globular transfer
Spray transfer
GMAW practice
Dip transfer
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
Gear burnishing is a process for
Surface finishing
Undercut gears
Cycloidal gears
Removing residual stresses from teeth roots
Carbide tipped tools usually have
Negative rake angle
Positive rake angle
Any rake angle
No rake 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
The chamfering is an essential operation after
Knurling
Rough turning
Boring
Thread cutting
The operation of producing grooves around the periphery of a cylindrical or conical workpiece is called
Profile milling
Gang milling
Saw milling
Helical milling
The cutting angle of a flat drill varies from
3° to 8°
20° to 30°
60° to 90°
90° to 120°