The ratio between two consecutive spindle speeds for a six-speed drilling machine using drills of diameter 6.25 to 25 mm size and at a cutting velocity of 18 m/min is
1.02
1.32
1.66
1.82
Correct Answer :
B. 1.32
Related Questions
The grade of grinding wheel depends upon
Hardness of the material being ground
Speed of wheel and work
Condition of grinding machine
All of these
The tool made of cemented carbide wear out faster at
Slow speeds
Medium speeds
Fast speeds
Very fast speeds
What is the type of welding defect caused due to poor deposition of weld rod is called?
Porosity
Undercut
Under fill
Crack
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 feed gear box for a screw cutting lathe is designed on the basis of
Geometric progression
Arithmetic progression
Harmonic progression
None of these
The method of centre less grinding used to produce taper is
In-feed grinding
Through feed grinding
End feed grinding
Any one of these
As the cutting speed increases, the tool cutting forces
Remain constant
Increases
Decreases
First increases and then decreases
In order to have interference fit, it is essential that the lower limit of the shaft should be
Greater than the upper limit of the hole
Lesser than the upper limit of the hole
Greater than the lower limit of the hole
Lesser than the lower limit of the hole
In which of the following machine, the work remains stationary and the tool is rotated?
Vertical boring machine
Horizontal boring machine
Precision boring machine
Jig boring machine
For machining a mild steel workpiece using carbide tool, the maximum material will be removed at a temperature of
50°C
100°C
175°C
275°C
High speed steel tools retain their hardness upto a temperature of
250°C
350°C
500°C
900°C
In abrasive jet machining, as the distance between the nozzle tip and the work surface increases, the material removal rate
Increases continuously
Decreases continuously
Decreases, becomes stable and then increases.
Increases, becomes stable and then decreases.
The example of snag grinding is
Trimming the surface left by sprues and risers on castings
Grinding the parting line left on castings
Removing flash on forgings
All of these
Slow speed of the spindle is necessary in
Thread cutting
Turning a work of larger diameter
Turning a hard or tough material
All of these
In drilling softer materials, the cutting speed is _________ as compared to harder materials.
Same
Low
High
None of these
In which of the following machine, the work rotates and the tool is stationary?
Vertical boring machine
Horizontal boring machine
Precision boring machine
Jig boring machine
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
If the flame of the welding torch is directed towards the progress of welding, then what will you call the welding technique?
Forehand welding
Flux cored ARC welding
Electro slag welding
Pulsed spray welding
The size of a shaper is given by
Stroke length
Motor power
Mass of machine
Rate size
Cutting fluids are used to
Cool the tool
Improve surface finish
Cool the workpiece
All of these
The cutting fluid mostly used for machining alloy steels is
Water
Soluble oil
Dry
Sulphurised mineral oil
Cast iron during machining produces
Continuous chips
Discontinuous chips
Continuous chips with built-up edge
None of these
The trade name of a nonferrous cast alloy composed of cobalt, chromium and tungsten is called
Ceramic
Stellite
Diamond
Cemented carbide
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
In an interchangeable assembly, shafts of size 25.000 -0.010⁺⁰⁰⁴⁰ mm mate with holes of size 25.000 -0.020⁺⁰⁰³⁰, the maximum interference (in microns) in the assembly is
40
30
20
10
The broaching operation in which the work moves past the stationary tool is called
Pull broaching
Push broaching
Surface broaching
Continuous broaching
The soft grade grinding wheels are denoted by the letters
A to H
I to P
Q to Z
A to P
Any number of equal divisions can be obtained on milling machine by
Direct indexing
Simple indexing
Compound indexing
Differential indexing
What is the type of joining process called, where the parts to be welded are kept in contact and rotated relative to each other and axial pressure is applied when the desired temperature is obtained?
Ultrasonic welding
Forge welding
Electron beam welding
Friction welding
The tap used to cut threads in a blind hole is
Taper tap
Second tap
Bottoming tap
Any one of these