Which of the following statement is correct in regard to centreless grinding?
The workpiece is supported throughout its entire length as grinding takes place.
It is a continuous process and adopted for production work.
It requires no holding device for the work.
All of the above
Correct Answer :
D. All of the above
Related Questions
In determining the various forces on the chip, Merchant assumed that the
Cutting edge of the tool is sharp and it does not make any flank contact with the workpiece
Only continuous chip without built-up-edge is produced
Cutting velocity remains constant
All of the above
A 15 mm drilling machine means that it can drill a hole
Of maximum diameter 15 mm
In 15 mm thick plates
Having cross-sectional area of 15 mm²
None of these
Climb milling is chosen while machining because
The chip thickness increase gradually
It enables the cutter to dig in and start the cut
The specific power consumption is reduced
Better surface finish can be obtained
A grinding wheel is said to be of _________ if the abrasive grains can be easily dislodged.
Soft grade
Medium grade
Hard grade
None of these
In electrochemical machining, the gap between the tool and work is kept as
0.1 mm
0.4 mm
0.35
0.75 mm
The obtuse angle, included between the chisel edge and the lip as viewed from the end of a drill, is called
Helix or rake angle
Point angle
Chisel edge angle
Lip clearance angle
A ring gauge is used to measure
Outside diameter but not roundness
Roundness but not outside diameter
Both outside diameter and roundness
Only external threads
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
In oblique cutting system, the cutting edge of the tool
May clear the width of the workpiece
May or may not clear the width of the workpiece
May not clear the width of the workpiece
Should always clear the width of the workpiece
Thread grinding requires work speed from
1 to 3 m/min
5 to 10 m/min
10 to 14 m/min
14 to 20 m/min
The helix angle of a drill is __________ for drilling brass.
Equal to 30°
Less than 30°
More than 30°
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
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
In drilling operation, the metal is removed by
Shearing
Extrusion
Shearing and extrusion
Shearing and compression
In a single point turning operation with a cemented carbide and steel combination having a Taylor exponent of 0.25, if the cutting speed is halved, then tool life will become
Half
Two times
Eight times
Sixteen times
The hardness of a grinding wheel is determined by the
Hardness of abrasive grains
Ability of the bond to retain abrasives
Hardness of the bond
Ability of the grinding wheel to penetrate the work piece
The taper on the lathe spindle is
1 in 10
1 in 15
1 in 20
1 in 30
The abrasive slurry used in ultrasonic machining contains fine particles of
Aluminium oxide
Boron carbide
Silicon carbide
Any one of these
Crater wear is predominant in
Carbon tool steels
Tungsten carbide tools
High speed steel tools
Ceramic tools
The parameter which completely defines the chip formation in a metal cutting process is
Shear angle
Chip-tool contact length
Both (A) and (B)
None 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 velocity of tool along the tool face is known as
Shear velocity
Chip velocity
Cutting velocity
Mean velocity
When 3-2-1 principle is used to support and locate a three dimensional work-piece during machining, the number of degrees of freedom that are restricted is
7
8
9
10
Twist drills are made of
High speed steel
Carbon steel
Stainless steel
Either (A) or (B)
When the metal is removed by erosion caused by rapidly recurring spark discharges between the tool and work, the process is known as
Electrochemical machining
Electro-discharge machining
Ultrasonic machining
None of these
Surface grinding is done to produce
Tapered surface
Flat surface
Internal cylindrical holes
All of these
The mechanism of material removal in EDM process is
Melting and Evaporation
Melting and Corrosion
Erosion and Cavitations
Cavitations and Evaporation
The tool life is affected by
Depth of cut
Cutting speed
Feed
All of these
A single point thread cutting tool should ideally hav
Zero rake angle
Positive rake angle
Negative rake angle
Point angle
The correct sequence of tool materials in increasing order of their ability to retain their hot hardness is
Carbide, ceramic, cermet, borazon
Ceramic, carbide, borazon, cermet
Cermet, carbide, ceramic, borazon
Borazon, ceramic, carbide, cermet