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
Correct Answer :
B. Soft and ductile materials
Related Questions
The rake angle required to machine brass by high speed steel tool is
0°
10°
20°
100°
What is the type of shielding gas for GTAW (Gas Tungsten Arc Welding) used for carbon steels only called?
Argon H₂
Argon CO₂
Argon Helium
Helium
Discontinuous chips are formed during machining of
Brittle metals
Ductile metals
Hard metals
Soft metals
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 correct sequence of the following parameters in order of their maximum to minimum influence on tool life is
Feed rate, depth of cut, cutting speed
Depth of cut, cutting speed, feed rate
Cutting speed, feed rate, depth of cut
Feed rate, cutting speed, depth of cut
Which of the following is the correct data structure for solid models?
Solid part - faces - edges - vertices
Solid part - edges - faces - vertices
Vertices - edges - faces - solid parts
Vertices - faces- edges - solid parts
It is required to cut screw threads of 2 mm pitch on a lathe. The lead screw has a pitch of 6 mm. If the spindle speed is 60 r.p.m., then the speed of lead screw will be
10 r.p.m.
20 r.p.m.
120 r.p.m.
180 r.p.m.
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
Glazing in grinding wheels takes place when the
Wheel is too hard or wheel revolves at a very high speed
Wheel is too soft or wheel revolves at a very slow speed
Wheel is too hard and wheel revolves at very slow speed
Wheel is too soft and wheel revolves at a very high speed
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
In machining metal, cutting force at the cutting edge is measured by a
Wattmeter
Dynamometer
Hydrometer
Pyrometer
The tool life is affected by
Depth of cut
Cutting speed
Feed
All of these
A bottoming tap has
Its end tapered for about three or four threads
Its end tapered for about eight or ten threads
Full threads for the whole of its length
None of the above
The effect of setting a boring tool above centre height leads to
Increase in the effective rake angle and a decrease in the effective clearance angle
Increase in both effective rake angle and effective clearance angle
Decrease in the effective rake angle and an increase in the effective clearance angle
Decrease in both effective rake angle and effective clearance angle
The tool life in case of a grinding wheel is the time
Between two successive regrinds of the wheel
Taken for the wheel to be balanced
Taken between two successive wheel dressings
Taken for a wear of 1 mm on its diameter
The width of cutting edge of a parting off tool varies from
3 to 12 mm
5 to 20 mm
8 to 30 mm
15 to 40 mm
The lathe spindles at the nose end have
Internal screw threads
External screw threads
No threads
Tapered threads
Allowance in limits and fits refers to
Maximum clearance between shaft and hole
Minimum clearance between shaft and hole
Difference between maximum and minimum sizes of hole
Difference between maximum and minimum sizes of shaft
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
Which among the NC operations given below are continuous path operations? Arc Welding (AW), Drilling (D), Laser Cutting of Sheet Metal (LC), Milling (M), Punching in Sheet Metal (P), Spot Welding (SW)
AW, LC and M
AW, D, LC and M
D, LC, P and SW
D, LC, and SW
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
The operation performed on a shaper is
Machining horizontal surface
Machining vertical surface
Machining angular surface
All of these
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
In up 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
High speed steel drills can be operated at about _________ the speed of high carbon steel drills.
One-half
One-fourth
Double
Four times
In centreless grinders, the regulating wheel is inclined at
0° to 8°
9° to 15°
16° to 20°
21° to 25°
The enlarging of an existing circular hole with a rotating single point tool is called
Boring
Drilling
Reaming
Internal turning
Lapping is an operation of
Making a cone-shaped enlargement of the end of a hole
Smoothing and squaring the surface around a hole
Sizing and finishing a small diameter hole
Producing a hole by removing metal along the circumference of a hollow cutting tool
In metal cutting operations, the shear angle is the angle made by the shear plane with the
Direction of the tool axis
Direction of tool travel
Perpendicular to the direction of the tool axis
Central plane of the workpiece
If a particular Fe-C alloy contains less than 0.83% carbon, it is called
High speed steel
Hypo eutectoid steel
Hyper eutectoid steel
Cast iron