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
Correct Answer :
A. Wheel is too hard or wheel revolves at a very high speed
Related Questions
The chuck preferred for quick setting and accurate centering of a job is
Four jaw independent chuck
Collect chuck
Three jaw universal chuck
Magnetic chuck
Segmental chips are formed during machining
Mild steel
Cast iron
High speed steel
High carbon steel
Which of the following operation is first performed?
Spot facing
Boring
Tapping
Drilling
If the tearing efficiency of a riveted joint is 50%, then ratio of rivet hole diameter to the pitch of rivets is
0.20
0.30
0.50
0.60
Work speed of circular electrode of 220 mm diameter for carrying out seam welding at 4 welds per cm on 1.6 mm thick mild steel tube. Welding cycle consists of 3 cycles on and 2 cycles off Power supply is at 50 Hz. Calculate R.P.M. and energy requirement of the above circular electrodes assuming effective resistance between electrodes as 100 ohm.
2.17 rpm, 600 joules
6.8 rpm, 6 joules
5.03 rpm, 600 joules
22 rpm, 600 joules
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
The helix angle of a drill is __________ for drilling brass.
Equal to 30°
Less than 30°
More than 30°
None of these
The tool life is affected by
Depth of cut
Cutting speed
Feed
All of these
The method of grinding used to produce a straight or tapered surface on a workpiece, is
Internal cylindrical grinding
Form grinding
External cylindrical grinding
Surface grinding
Surface grinding is done to produce
Tapered surface
Flat surface
Internal cylindrical holes
All of these
Side relief angle of a single point 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 tool
Between the surface of the flank immediately below the point and a line drawn from the point perpendicular to the base
For softer materials, the point angle of the drill is kept
Equal to 118°
Less than 118°
More than 118°
Any one of these
A left 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
Which of the following statement is wrong?
The diamond is the hardest tool material and can run at cutting speeds about 50 times that of high speed steel tool.
The ceramic tools can be used at cutting speeds 40 times that of high speed steel tools.
The cemented carbide tools can be used at cutting speeds 10 times that of high speed steel tools.
The ceramic tools can withstand temperature upto 600°C only.
What is the method of brazing used to join relatively small assemblies made from materials that either do not oxidize at the brazing temperature or can be protected from oxidation with a flux?
Torch brazing
Dip brazing
Resistance brazing
Furnace brazing
For turning small taper on long workpiece, the suitable method is
By a form tool
By setting over the tail stock
By a taper turning attachment
By swivelling the compound rest
The increase in depth of cut and feed rate __________ surface finish.
Improves
Deteriorates
Does not effect
None of these
A diamond locating pin is used in jigs and fixtures because
Diamond is very hard and wear resistant
It occupies very little space
It helps in assembly with tolerance on centre distance
It has a long life
A type of welding flows, which is the result of a perfect proportion and mixture of acetylene and oxygen and is used for fusion welding of steel and cast iron, is
Carburizing flame
Oxidizing flame
Oxy-acetylene flame
Neutral flame
During normalizing process of steel, the specimen is heated
Between the upper and lower critical temperature and cooled in still air.
Above the upper critical temperature and cooled in furnace.
Above the upper critical temperature and cooled in still air.
Between the upper and lower critical temperature and cooled in furnace.
In a plain milling cutter, the chip space between the back of one tooth and the face of the next tooth is called
Face
Fillet
Gash
Land
Which type of motor is not used in axis or spindle drives of CNC machine tools?
Induction motor
DC servo motor
Stepper motor
Linear servo motor
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
The type of tool used on milling machine and broaching machine is
Single point cutting tool
Two point cutting tool
Three point cutting tool
Multipoint cutting tool
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
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
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
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
The depth of cut in drilling is __________ the drill diameter.
Equal to
One-fourth
One-half
Double
Hardness of steel greatly improves with
Annealing
Cyaniding
Normalizing
Tempering