In Oxyacetylene gas welding, temperature at the inner cone of the flame is around
3500⁰C
3200⁰C
2900⁰C
2550⁰C
Correct Answer :
B. 3200⁰C
Related Questions
In which of the following machine, the work is usually rotated while the drill is fed into work?
Sensitive drilling machine
Radial drilling machine
Gang drilling machine
Deep hole drilling machine
Chip breakers are used to
Increase tool life
Remove chips from bed
Break the chips into short segments
To minimise heat generation
Which of the following statement is incorrect with reference of lathe cutting tools?
The flank of the tool is the surface or surfaces below and adjacent to the cutting edges
The nose is the corner, arc or chamfer joining the side cutting and the end cutting edges
The heel is that part of the tool which is shaped to produce the cutting edges and face
The base is that surface of the shank which bears against the support and takes tangent pressure of the cut
The surface finish is improved by the increase in
Cutting speed
Nose radius
True rake angle
All of these
In ECM, the material removal is due to
Corrosion
Erosion
Fusion
Ion displacement
The abrasive recommended for grinding materials of low tensile strength is
Silicon carbide
Aluminium oxide
Sand stone
Diamond
The enlarging of an existing circular hole with a rotating single point tool is called
Boring
Drilling
Reaming
Internal turning
A left hand tool on a lathe cuts most efficiently when it travels
From left to right end of the lathe bed
From right to left end of the lathe bed
With the help of a compound slide
Across the bed
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.
The grooving is an operation of
Bevelling the extreme end of a workpiece
Embossing a diamond shaped pattern on the surface of a workpiece
Reducing the diameter of a workpiece over a very narrow surface
Enlarging the end of a hole cylindrically
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 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°
What is the welding defect caused due to improper control and poor removal of slog between passes called?
Mismatch
Under fill
Crack
Porosity
Which one of the following is a solid state joining process?
Gas tungsten arc welding
Resistance spot welding
Friction welding
Submerged arc welding
Gear finishing operation is called
Shaping
Milling
Hobbing
Burnishing
In machining metal, cutting force at the cutting edge is measured by a
Wattmeter
Dynamometer
Hydrometer
Pyrometer
In centre less grinders, the maximum angular adjustment of the regulating wheel is
5°
10°
15°
20°
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 relation between the tool life (T) in minutes and cutting speed (V) in m/min is (where n = An exponent, which depends upon the tool and workpiece, and C = A constant)
VnT = C
VTn = C
Vn/T = C
V/Tn = C
The operation performed on a shaper is
Machining horizontal surface
Machining vertical surface
Machining angular surface
All 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
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
The trade name of a nonferrous cast alloy composed of cobalt, chromium and tungsten is called
Ceramic
Stellite
Diamond
Cemented carbide
The process of changing the shape of grinding wheel as it becomes worn due to breaking away of the abrasive and bond, is called
Truing
Dressing
Facing
Clearing
An operation of embossing a diamond shaped pattern on the surface of a workpiece, is known as
Counter-boring
Grooving
Knurling
Facing
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
A CNC vertical milling machine has to cut a straight slot of 10 mm width and 2mm depth by a cutter of 10 mm diameter between points (0,0) and (100,100) on the XY plane (dimensions in mm). The feed rate used for milling is 50 mm/min, milling time for the slot (in seconds) is
120
170
180
240
The operation of smoothing and squaring the surface around a hole is known as
Counter-sinking
Counter-boring
Trepanning
Spot facing
The facing is an operation of
Bevelling the extreme end of a workpiece
Embossing a diamond shaped pattern on the surface of a workpiece
Reducing the diameter of a workpiece over a very narrow surface
Machining the ends of a workpiece to produce a flat surface square with the axis
Green sand mould indicates that
Polymeric mould has been cured
Mould has been totally dried
Mould is green in colour
Mould contains moisture