A fine 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 :
A. Hard and brittle materials
Related Questions
The abrasive slurry used in ultrasonic machining contains fine particles of
Aluminium oxide
Boron carbide
Silicon carbide
Any one 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
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
In drilling softer materials, the cutting speed is _________ as compared to harder materials.
Same
Low
High
None of these
Low helix angle drills are preferred for drilling holes in
Plastics
Copper
Cast steel
Carbon steel
The angle made by the face of the tool and the plane parallel to the base of cutting tool is called
Rake angle
Cutting angle
Clearance angle
Lip angle
In an interchangeable assembly, shafts of size 25.000 -0.0100⁺⁰⁰⁴⁰ mm mate with holes of size 25.000 -0.010⁺⁰⁰²⁰ mm. The maximum possible clearance in the assembly will be
10 microns
20 microns
30 microns
60 microns
The strength of a brazed joint
Decreases with increase in gap between the two joining surfaces
Increases with increase in gap between the two joining surfaces
Decreases up to certain gap between the two joining surfaces beyond which it increases
Increases up to certain gap between the two joining surfaces beyond which it decreases
In hot machining, tool is made of
Tungsten carbide
Brass or copper
Diamond
Stainless steel
A lead-screw with half nuts in a lathe, free to rotate in both directions has
V-threads
Whitworth threads
Buttress threads
Acme threads
Internal gears can be made by
Hobbing
Shaping with pinion cutter
Shaping with rack cutter
Milling
Ceramic cutting tools are
Made by cold pressing of aluminium oxide powder
Available in the form of tips
Brittle and have low bending strength
All of these
A jig is defined as a device which
Holds and locates a workpiece and guides and controls one or more cutting tools
Holds and locates a workpiece during an inspection or for a manufacturing operation
Is used to check the accuracy of workpiece
All of the above
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
The grinding wheel speed (surface speed in m/min) usually varies from
500 to 1000
1000 to 1500
1500 to 2000
2000 to 2500
Tool life is measured by the
Number of pieces machined between tool sharpenings
Time the tool is in contact with the job
Volume of material removed between tool sharpenings
All of the above
The factor responsible for the formation of discontinuous chips 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 process of removing metal by a cutter which is rotated in the same direction of travel of workpiece, is called
Up milling
Down milling
Face milling
End milling
When the temperature of a solid metal increases,
Strength of the metal decreases but ductility increases
Both strength and ductility of the metal decreases
Both strength and ductility of the metal increases
Strength of the metal increases but ductility decreases
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 lathe spindles at the nose end have
Internal screw threads
External screw threads
No threads
Tapered threads
In grinding irregular, curved, tapered, convex and concave surfaces, the grinder used is
Cylindrical grinder
Internal grinder
Surface grinder
Tool and cutter grinder
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
Gear lapping is an operation
After heat treatment
Prior to heat treatment
For gear reconditioning
None of these
Dielectric is used in
Electrochemical machining
Ultrasonic machining
Electro discharge machining
Laser machining
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
In which type of welding a gas shield, a consumable electrode is used and the welding can be done in all positions.
ARC welding
Submerged ARC welding
TIG welding
MIG welding
The tool life is said to be over if
Poor surface finish is obtained
There is sudden increase in cutting forces and power consumption
Overheating and fuming due to heat of friction starts
All of the above
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
The capacity of a material to be welded under the imposed fabrication conditions into a specific, suitably designed structure and to perform satisfactorily in the intended service is known as?
Weldment
Weld tab
Weldability
Tack weld