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
Correct Answer :
A. Of maximum diameter 15 mm
Related Questions
The method of centre less grinding used to produce taper is
In-feed grinding
Through feed grinding
End feed grinding
Any one of these
In reaming process
Metal removal rate is high
High surface finish is obtained
High form accuracy is obtained
High dimensional accuracy is obtained
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
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
The tool life is affected by
Depth of cut
Cutting speed
Feed
All of these
In order to achieve a specific surface finish in single point turning, the most important factor to be controlled is
Depth of cut
Cutting speed
Feed
Tool rake angle
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
In a metal arc welding process, a gas metal arc welding with magnetized flux is used and can be done in all the positions i.e. flat position, vertical position or inclined position.
Globular transfer
Spray transfer
GMAW practice
Dip transfer
The angle formed by the leading edge of the land with a plane having the axis of the drill, is called
Helix or rake angle
Point angle
Chisel edge angle
Lip clearance angle
Stellite preserves hardness upto a temperature of
350°C
500°C
900°C
1100°C
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
Which of the following statement is wrong?
The larger side rake angle produces chipping.
The smaller rake angle produces excessive wear and deformation in tool.
The side cutting edge angle (less than 15°) increases tool life.
The increase in nose radius decreases tool life.
In hot machining, tool is made of
Tungsten carbide
Brass or copper
Diamond
Stainless steel
When the end of a tap is tapered for about three or four threads, it is known as a
Taper tap
Bottoming tap
Second tap
None of these
In order to obtain a surface finish in the range of 0.75 μm to 1.25 μm , the operation used is called.
Grinding
Lapping
Honing
Buffing
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
Which of the following statement is correct about hot machining?
It requires less power than machining metals at room temperature.
The rate of tool wear is lower.
It is used for machining high strength and high temperature resistant materials.
All of the above
The cutting speed for drilling copper with high speed steel drills varies from
10 to 20 m/min
18 to 30 m/min
24 to 45 m/min
60 to 90 m/min
In Oxyacetylene gas welding, temperature at the inner cone of the flame is around
3500⁰C
3200⁰C
2900⁰C
2550⁰C
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
Lathe bed is made of
Mild steel
Alloy steel
Pig iron
Chilled cast iron
Gear burnishing is a process for
Surface finishing
Undercut gears
Cycloidal gears
Removing residual stresses from teeth roots
The lathe spindles are usually made hollow and provided with
Internal taper
External taper
Internal and external taper
No taper
The cutting speed of a drill depends upon the
Material of drill
Type of material to be drilled
Quality of surface finish desired
All of these
A process of removing metal by pushing or pulling a cutting tool is called
Up milling
Down milling
Forming
Broaching
The operation of smoothing and squaring the surface around a hole is known as
Counter-sinking
Counter-boring
Trepanning
Spot facing
Side rake angle of a single point cutting 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 the tool
Between the surface of the flank immediately below the point and a line drawn from the point perpendicular to the base
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
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
In ultrasonic machining, the metal is removed by
Using abrasive slurry between the tool and work
Direct contact of tool with the work
Maintaining an electrolyte between the work and tool in a very small gap between the two
Erosion caused by rapidly recurring spark discharges between the tool and work