Which of the following statement is wrong about ultrasonic machining?
It is best suited for machining hard and brittle materials
It cuts materials at very slow speeds
It removes large amount of material
It produces good surface finish
Correct Answer :
C. It removes large amount of material
Related Questions
Gears can be best produced on mass production by
Shaping
Casting
Forming
Hobbing
Flank wear depends upon the
Hardness of the work and tool material at the operating temperature
Amount and distribution of hard constituents in the work material
Degree of strain hardening in the chip
All of these
Crack in grinding wheel is developed due to
High temperature developed at the contact of the wheel face and work
Grinding hard work
Low speed of wheel
High speed of wheel
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
A process of removing metal by pushing or pulling a cutting tool is called
Up milling
Down milling
Forming
Broaching
The relation between tool life (T) and cutting speed (V) is VTn = Constant. In this relation, the value of n depends upon
Work material
Tool material
Working conditions
Type of chip produced
The cutting speed for drilling aluminium, brass and bronze with carbon steel drills is _________ cutting speed for drilling mild steel with high speed steel drills.
Equal to
Less than
More than
None of these
A shaft has a dimension, φ9 +0.025⁺⁰⁰⁰⁹, the respective values of fundamental deviation and tolerance are
- 0.025, ±0.008
- 0.025, 0.016
- 0.009, ± 0.008
- 0.009, 0.016
In drilling Bakelite and fibrous plastics, the point angle of a drill is
90°
118°
135°
150°
Down milling is also called
Conventional milling
Climb milling
End milling
Face milling
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
In centreless grinders, the regulating wheel is inclined at
0° to 8°
9° to 15°
16° to 20°
21° to 25°
In ECM, the material removal is due to
Corrosion
Erosion
Fusion
Ion displacement
Crater wear is mainly due to the phenomenon known as
Adhesion of metals
Oxidation of metals
Diffusion of metals
All of these
Which of the following statement is wrong as regard to down milling?
It can not be used on old machines due to backlash between the feed screw of the table and the nut.
The chips are disposed off easily and do not interfere with the cutting.
The surface milled appears to be slightly wavy.
The coolant can be poured directly at the cutting zone where the cutting force is maximum.
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
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
The abrasive recommended for grinding materials of high tensile strength is
Silicon carbide
Aluminium oxide
Sand stone
Diamond
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
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
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
In electro discharge machining, tool is made of
Brass
Copper
Copper tungsten alloy
All 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
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
The negative rake is usually provided on
High carbon steel tools
High speed steel tools
Cemented carbide tools
All of these
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
In hot machining, the work is heated by
Simple heating
Flame heating
Induction heating
Any one of these
For machining a mild steel workpiece by a high speed steel tool, the average cutting speed is
5 m/min
10 m/min
15 m/min
30 m/min
The broaching operation in which the work moves past the stationary tool is called
Pull broaching
Push broaching
Surface broaching
Continuous broaching
The operation of smoothing and squaring the surface around a hole is known as
Counter-sinking
Counter-boring
Trepanning
Spot facing