The cutting fluid mostly used for machining steel is
Water
Soluble oil
Dry
Heavy oils
Correct Answer :
B. Soluble oil
Related Questions
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
Which of the following is the correct data structure for solid models?
Solid part - faces - edges - vertices
Solid part - edges - faces - vertices
Vertices - edges - faces - solid parts
Vertices - faces- edges - solid parts
Tool life is measured by the
Number of pieces machined between tool sharpenings
Time the tool is in contact with the job
Volume of material removed between tool sharpenings
All of the above
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
The capacity of a material to be welded under the imposed fabrication conditions into a specific, suitably designed structure and to perform satisfactorily in the intended service is known as?
Weldment
Weld tab
Weldability
Tack weld
The chuck preferred for quick setting and accurate centering of a job is
Four jaw independent chuck
Collect chuck
Three jaw universal chuck
Magnetic chuck
The tool life in case of a grinding wheel is the time
Between two successive regrinds of the wheel
Taken for the wheel to be balanced
Taken between two successive wheel dressings
Taken for a wear of 1 mm on its diameter
The usual value of the helix angle of a drill is
20°
30°
45°
60°
In an interchangeable assembly, shafts of size 25.000 -0.0100⁺⁰⁰⁴⁰ mm mate with holes of size 25.000 -0.010⁺⁰⁰²⁰ mm. The maximum possible clearance in the assembly will be
10 microns
20 microns
30 microns
60 microns
What is the type of shielding gas for GTAW (Gas Tungsten Arc Welding) used for carbon steels only called?
Argon H₂
Argon CO₂
Argon Helium
Helium
The chamfering is an essential operation after
Knurling
Rough turning
Boring
Thread cutting
In machining metals, chips break due to __________ of work material.
Toughness
Ductility
Elasticity
Work hardening
Which of the following parameters influence the axial feed rate in centerless grinding?
Regulating wheel diameter
Speed of the regulating wheel
Angle between the axes of grinding and regulating wheels
All of the above
In a CNC program block, N002 GO2 G91 X40 Z40......, GO2 and G91 refer to
Circular interpolation in counter clockwise direction and incremental dimension
Circular interpolation in counter clockwise direction and absolute dimension
Circular interpolation in clockwise direction and incremental dimension
Circular interpolation in clockwise direction and absolute dimension
It is required to cut screw threads of 2 mm pitch on a lathe. The lead screw has a pitch of 6 mm. If the spindle speed is 60 r.p.m., then the speed of lead screw will be
10 r.p.m.
20 r.p.m.
120 r.p.m.
180 r.p.m.
High speed steel tools retain their hardness upto a temperature of
250°C
350°C
500°C
900°C
The type of tool used on lathe, shaper and planer is
Single point cutting tool
Two point cutting tool
Three point cutting tool
Multipoint cutting tool
Tumbler gears in lathe are used to
Reduce the spindle speed
Cut gears
Give desired direction of movement to the lathe carriage
Drill a workpiece
A taper tap has
Its end tapered for about three or four threads
Its end tapered for about eight or ten threads
Full threads for the whole of its length
None of the above
The abrasive recommended for grinding materials of low tensile strength is
Silicon carbide
Aluminium oxide
Sand stone
Diamond
Which of the following statement is wrong as regard to down milling?
It can not be used on old machines due to backlash between the feed screw of the table and the nut.
The chips are disposed off easily and do not interfere with the cutting.
The surface milled appears to be slightly wavy.
The coolant can be poured directly at the cutting zone where the cutting force is maximum.
If a particular Fe-C alloy contains less than 0.83% carbon, it is called
High speed steel
Hypo eutectoid steel
Hyper eutectoid steel
Cast iron
When the temperature of a solid metal increases,
Strength of the metal decreases but ductility increases
Both strength and ductility of the metal decreases
Both strength and ductility of the metal increases
Strength of the metal increases but ductility decreases
The lathe centres are provided with standard taper known as
Morse taper
Seller's taper
Chapman taper
Brown and Sharpe taper
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 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
In electro-discharge machining, dielectric is used to
Help in the movement of the sparks
Control the spark discharges
Act as coolant
All of these
The advantage of a broaching operation is that
Rate of production is very high
High accuracy and high class of surface finish is possible
Roughing and finishing cuts are completed in one pass of the tool
All of the above
A ring gauge is used to measure
Outside diameter but not roundness
Roundness but not outside diameter
Both outside diameter and roundness
Only external threads
Negative rakes are used for
Carbide tools
Heavy loads
Harder materials
All of these