What is the type of welding defect is caused due to stresses on heating and cooling called?
Incomplete penetration
Shrinkage void
Slag Entrapment (Inclusions)
Incomplete fusion
Correct Answer :
B. Shrinkage void
Related Questions
A hole is of dimension φ = 9 ₊0⁺⁰⁰¹⁵ mm. The corresponding shaft is of dimension φ = 9 ₊0.001⁺⁰⁰¹⁰ mm. The resulting assembly has
Loose running fit
Close running fit
Transition fit
Interference fit
The lip clearance angle is the angle formed by the
Leading edge of the land with a plane having the axis of the drill
Flank and a plane at right angles to the drill axis
Chisel edge and the lip as viewed from the end of a drill
None of the above
Thread grinding requires work speed from
1 to 3 m/min
5 to 10 m/min
10 to 14 m/min
14 to 20 m/min
A coarse grained grinding wheel is used to grind
Hard and brittle materials
Soft and ductile materials
Hard and ductile materials
Soft and brittle materials
The chuck used for setting up of heavy and irregular shaped work should be
Four jaw independent chuck
Three jaw universal chuck
Magnetic chuck
Drill chuck
The hardness of a grinding wheel is specified by
Brinell hardness number
Rockwell hardness number
Vickers pyramid number
Letter of alphabet
The negative rake is usually provided on
High carbon steel tools
High speed steel tools
Cemented carbide tools
All of these
With the same tool life, the maximum material per minute is removed by
Increasing the cutting speed
Decreasing the cutting speed
Increasing the depth of cut
Increasing the feed rate
Chemical milling operation is performed
On universal milling machine
On plain milling machine
In a tank containing an etching solution
Any one of these
Cast iron during machining produces
Continuous chips
Discontinuous chips
Continuous chips with built-up edge
None of these
The crystal structure of austenite is
Body centred cubic
Base centred cubic
Hexagonal closed packed
Body centred tetragonal
The object of caulking in a riveted joint is to make the joint
Free from corrosion
Stronger in tension
Free from stresses
Leak-proof
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
Low helix angle drills are preferred for drilling holes in
Plastics
Copper
Cast steel
Carbon steel
The helix angle of a drill is __________ for drilling brass.
Equal to 30°
Less than 30°
More than 30°
None of these
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
The strength of a brazed joint
Decreases with increase in gap between the two joining surfaces
Increases with increase in gap between the two joining surfaces
Decreases up to certain gap between the two joining surfaces beyond which it increases
Increases up to certain gap between the two joining surfaces beyond which it decreases
Which of the following statement is correct about EDM machining?
It can machine hardest materials.
It produces high degree of surface finish.
The tool and work are never in contact with each other.
All of these
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
The specific cutting energy used for establishing the machinability of the metal depends upon its
Coefficient of friction
Microstructure
Work hardening characteristics
All of these
A fine grained grinding wheel is used to grind
Hard and brittle materials
Soft and ductile materials
Hard and ductile materials
Soft and brittle materials
Which of the following operation is first performed?
Spot facing
Boring
Tapping
Drilling
In Oxyacetylene gas welding, temperature at the inner cone of the flame is around
3500⁰C
3200⁰C
2900⁰C
2550⁰C
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 broaching operation in which the work moves past the stationary tool is called
Pull broaching
Push broaching
Surface broaching
Continuous broaching
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 carbide tools operating at very low cutting speeds (below 30 m/min)
Reduces tool life
Increases tool life
Have no effect on tool life
Spoils the work piece
A solid cylinder of diameter 100 mm and height 50 mm is forged between two frictionless flat dies to a height of 25mm. The percentage change in diameter is
0
2.07
20.7
41.4
The tool may fail due to
Cracking at the cutting edge due to thermal stresses
Chipping of the cutting edge
Plastic deformation of the cutting edge
All of these
The common welding error that occurs due to wrong speed, faulty preparation, and high / low current, improper electrode size is called?
Distortion
Warping
Porous weld
Poor fusion