Two streams of liquid metal which are not hot enough to fuse properly result into a casting defect known as
Cold shut
Swell
Sand wash
Scab
Correct Answer :
A. Cold shut
Related Questions
What is the type of welding defect caused due to poor deposition of weld rod is called?
Porosity
Undercut
Under fill
Crack
The correct sequence of tool materials in increasing order of their ability to retain their hot hardness is
Carbide, ceramic, cermet, borazon
Ceramic, carbide, borazon, cermet
Cermet, carbide, ceramic, borazon
Borazon, ceramic, carbide, cermet
Tool life is generally better when
Grain size of the metal is large
Grain size of the metal is small
Hard constituents are present in the microstructure of the tool material
None of the above
In oblique cutting system, the maximum chip thickness
Occurs at the middle
May not occur at the middle
Depends upon the material of the tool
Depends upon the geometry of the tool
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
In an orthogonal cutting, the depth of cut is halved and the feed rate is double. If the chip thickness ratio is unaffected with the changed cutting conditions, the actual chip thickness will be
Doubled
Halved
Quadrupled
Unchanged
Which of the following operations can be performed with milling cutters?
Cutting key ways on shafts
Cutting external screw threads
Cutting teeth of spur gears
All of these
Which type of motor is not used in axis or spindle drives of CNC machine tools?
Induction motor
DC servo motor
Stepper motor
Linear servo motor
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
The tool material, for faster machining, should have
Wear resistance
Red hardness
Toughness
All of these
The size of abrasive grain required in a grinding wheel depends upon the
Amount of material to be removed
Hardness of material being ground
Finish desired
All of these
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
An operation of embossing a diamond shaped pattern on the surface of a workpiece, is known as
Counter-boring
Grooving
Knurling
Facing
Broaching is applied for machining
Internal and external surfaces
Round or irregular shaped holes
External flat and contoured surfaces
All of these
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
The correct sequence of the following parameters in order of their maximum to minimum influence on tool life is
Feed rate, depth of cut, cutting speed
Depth of cut, cutting speed, feed rate
Cutting speed, feed rate, depth of cut
Feed rate, cutting speed, depth of cut
Which of the following arc welding processes does not use consumable electrodes?
GMAW
GTAW
Submerged Arc Welding
None of these
The angle between the face and flank of the single point cutting tool is known as
Rake angle
Clearance angle
Lip angle
Point angle
The grinding operation is a
Shaping operation
Forming operation
Surface finishing operation
Dressing operation
The cutting speed for drilling __________ with high speed steel drills is 24 to 45 m/min.
Mild steel
Copper
Aluminium
Brass
Trepanning is an operation of
Making a cone-shaped enlargement of the end of a hole
Smoothing and squaring the surface around a hole
Sizing and finishing a small diameter hole
Producing a hole by removing metal along the circumference of a hollow cutting tool
The cutting force in punching and blanking operations mainly depends on
The modulus of elasticity of metal
The shear strength of metal
The bulk modulus of metal
The yield strength of metal
Jigs are used
For holding and guiding the tool in drilling, reaming or tapping operations
For holding the work in milling, grinding, planing or turning operations
To check the accuracy of workpiece
None of the above
In Oxyacetylene gas welding, temperature at the inner cone of the flame is around
3500⁰C
3200⁰C
2900⁰C
2550⁰C
An expendable pattern is used in
Slush casting
Squeeze casting
Centrifugal casting
Investment casting
The primary purpose of a sprue in a casting mould is to
Feed the casting at a rate consistent with the rate of solidification.
Act as a reservoir for molten metal
Feed molten metal from the pouring basin to the gate
Help feed the casting until all solidification takes place
The purpose of jigs and fixtures is to
Increase machining accuracy
Facilitate interchangeability
Decrease expenditure on quality control
All of these
The tail stock set over method of taper turning is preferred for
Internal tapers
Small tapers
Long slender tapers
Steep tapers
In metal cutting operations, the shear angle is the angle made by the shear plane with the
Direction of the tool axis
Direction of tool travel
Perpendicular to the direction of the tool axis
Central plane of the workpiece
The method of grinding used to produce internal cylindrical holes and tapers, is
Internal cylindrical grinding
Form grinding
External cylindrical grinding
Surface grinding