Crater wear is predominant in
Carbon tool steels
Tungsten carbide tools
High speed steel tools
Ceramic tools
Correct Answer :
B. Tungsten carbide tools
Related Questions
In a shaper, the metal is removed during
Forward stroke
Return stroke
Both the forward and return strokes
Neither the forward nor the return stroke
NC contouring is an example of
Continuous path positioning
Point-to-point positioning
Absolute positioning
Incremental positioning
Which of the following parameters govern the value of shear angle in continuous chip formation?
True feed
Chip thickness
Rake angle of the cutting tool
All of these
Larger than 15° side cutting edge angle
Increases tool life
Decreases tool life
Produces chipping and decreases tool life
Results in excessive stress concentration and greater heat generation
Segmental chips are formed during machining
Mild steel
Cast iron
High speed steel
High carbon steel
The method of grinding used to produce internal cylindrical holes and tapers, is
Internal cylindrical grinding
Form grinding
External cylindrical grinding
Surface grinding
In up-cut milling the work piece is fed
Against the rotating cutter
At angle of 60° to the cutter
In the direction of the cutter
At the right angle to the cutter
The type of reamer used for reaming soft aluminium or copper, is
Straight fluted reamer
Left hand spiral fluted reamer
Right hand spiral fluted reamer
Any one of these
The relief or clearance at the cutting edge of a flat drill varies from
3° to 8°
20° to 30°
60° to 90°
90° to 120°
The type of reamer used for reaming operation in a blind hole, is
Straight fluted reamer
Left hand spiral fluted reamer
Right hand spiral fluted reamer
Any one of these
The hole to be drilled for tapping is _________ the outside diameter of the thread on the tap.
Equal to
Smaller than
Greater than
None of these
The hard grade grinding wheels are denoted by the letters
A to H
I to P
Q to Z
A to P
For machining a cast iron workpiece by a high speed steel tool, the average cutting speed is
10 m/min
15 m/min
22 m/min
30 m/min
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
An expendable pattern is used in
Slush casting
Squeeze casting
Centrifugal casting
Investment casting
A drill mainly used in drilling brass, copper or softer materials, is
Flat drill
Straight fluted drill
Parallel shank twist drill
Tapered shank twist drill
A twist drill is a
Side cutting tool
Front cutting tool
End cutting tool
None of these
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
Which of the following process is used for preparing parts having large curved surfaces and thin sections?
Hot machining
Ultrasonic machining
ECM process
Chemical milling
Carbide tipped tools usually have
Negative rake angle
Positive rake angle
Any rake angle
No rake angle
Which of the following statement is correct regarding grinding of high carbon steel?
Grinding at high speed results in the reduction of chip thickness and cutting forces per grit.
Aluminium oxide wheels are employed.
The grinding wheel has to be of open structure.
All of the above
Gear burnishing is a process for
Surface finishing
Undercut gears
Cycloidal gears
Removing residual stresses from teeth roots
Glazing in grinding wheels can be decreased by
Using a harder wheel or by increasing the wheel speed
Using a softer wheel or by decreasing the wheel speed
Using a harder wheel or by decreasing the wheel speed
Using a softer wheel or by increasing the wheel speed
What is the type of welding defect caused due to poor deposition of weld rod is called?
Porosity
Undercut
Under fill
Crack
In machining metal, cutting force at the cutting edge is measured by a
Wattmeter
Dynamometer
Hydrometer
Pyrometer
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
Which of the following statement is correct about nose radius?
It improves tool life
It improves the surface finish
Both (A) and (B)
None of these
For softer materials, the point angle of the drill is kept
Equal to 118°
Less than 118°
More than 118°
Any one of these
The chamfering is an essential operation after
Knurling
Rough turning
Boring
Thread cutting
In which of the following milling machine, the table can be tilted in a vertical plane by providing a swivel arrangement at the knee?
Universal milling machine
Plain milling machine
Universal milling machine
Hand milling machine