Machine Tools

The grinding wheel used to provide the best surface finish is

The preparatory functions in Computer Numerical Controlled (CNC) machine programming are denoted by the alphabet

A flat surface of a C60 steel having dimensions of 100 mm (length) × 200 mm (width) is produced by a HSS slab mill cutter. The 8-toothed cutter has 100 mm diameter and 200 mm width. The feed per tooth is 0.1 mm, cutting...

A block of length $$200$$ $$mm$$ is machined by a slab milling cutter $$34$$ $$mm$$ in diameter. The depth of cut and table feed are set at $$2$$ $$mm$$ and $$18$$ $$mm/minute,$$ respectively. Considering the approach an...

Circular arc on a part profile is being machined on a vertical $$CNC$$ milling machine. $$CNC$$ part program using metric units with absolute dimensions is listed below: $$\eqalign{ & N60\,\,\,\,G01\,\,\,\,X\,30\,\,\,\,Y...

Metric thread of $$0.8$$ $$mm$$ pitch is to be cut on a lathe. Pitch of the lead screw is $$1.5$$ $$mm.$$ If the spindle rotates at $$1500$$ $$rpm,$$ the speed of rotation of the lead screw $$(rpm)$$ will be ____________...

The following data is applicable for a turning operation. The length of job is $$900$$ $$mm,$$ diameter of job is $$200$$ $$mm,$$ feed rate is $$0.25$$ $$mm/rev$$ and optimum cutting speed is $$300$$ $$m/min.$$ The machi...

Internal gears are manufactured by

The function of interpolator in a $$CNC$$ machine controller is to

In a machining operation, if the generatrix and directrix both are straight lines, the surface obtained is

A shaft of length $$90$$ $$mm$$ has a tapered portion of length $$55$$ $$mm.$$ The diameter of the taper is $$80$$ $$mm$$ at one end and $$65$$ $$mm$$ at the other. If the taper is made by tailstock set over method, the...

In a $$CNC$$ milling operation, the tool has to machine the circular arc from point $$(20, 20)$$ to $$(10, 10)$$ at sequence number $$5$$ of the $$CNC$$ part program. If the center of the arc is at $$(20, 10)$$ and the m...

For machining a rectangular island represented by coordinates $$P(0,0), Q(100,0), R(100,50)$$ and $$S(0,50)$$ on a casting using $$CNC$$ milling machine, an end mill with a diameter of $$16$$ $$mm$$ is used. The trajecto...

A cast iron block of $$200$$ $$mm$$ length is being shaped in a shaping machine with a depth of cut of $$4$$ $$mm,$$ feed of $$0.25$$ $$mm/stroke$$ and the tool principal cutting edge angle of $${30^ \circ }.$$ Number of...

Two separate slab milling operations, $$1$$ and $$2,$$ are performed with identical milling cutters. The depth of cut in operation $$2$$ is twice that in operation $$1.$$ The other cutting parameters are identical. The r...

A hole of $$20$$ $$mm$$ diameter is to be drilled in a steel block of $$40$$ $$mm$$ thickness. The drilling is performed at rotational speed of $$400$$ $$rpm$$ and feed rate of $$0.1$$ $$mm/rev.$$ The required approach a...

A steel bar $$200$$ $$mm$$ in diameter is turned at a feed of $$0.25$$ $$mm/rev$$ with a depth of cut of $$4$$ $$mm.$$ The rotational speed of the work piece is $$160$$ $$rpm.$$ The material removal rate in $$m{m^3}/s$$...

In a single pass drilling operation, a through hole of $$15$$ $$mm$$ diameter is to be drilled in a steel plate of $$50$$ $$mm$$ thickness. Drill spindle speed is $$500$$ $$rpm,$$ feed is $$0.2$$ $$mm/rev$$ and drill poi...

A $$CNC$$ vertical milling machine has to cut a straight slot of $$10$$ $$mm$$ width and $$2$$ $$mm$$ depth by a cutter of $$10$$ $$mm$$ diameter between points $$(0, 0)$$ and $$(100, 100)$$ on the $$XY$$ plane (dimensio...

In a $$CNC$$ program block, $$N002\,\,\,\,G02\,\,\,\,G91\,\,\,\,X40\,\,\,\,Z40....,\,\,\,\,G02\,\,\,\,\& \,\,\,\,G91$$ refer to

Internal gear cutting operation can be performed by

Which type of motor is used in axial or spindle drives of $$CNC$$ m/c tools

If each abrasive grain is viewed as a cutting tool, then which of the following represents the cutting parameters in common grinding operations?

$$NC$$ contouring is an example of

A $$600$$ $$mm$$ $$ \times \,\,30\,\,mm$$ flat surface of a plate is to be finish machined on a shaper. The plate has been fixed with the $$600$$ $$mm$$ side along the tool travel direction. If the tool over-travel at ea...

Which among the $$NC$$ operations given below are continuous path operations? Arc Welding $$(A$$ $$W)$$, Milling $$(M),$$ Drilling $$(D),$$ Punching in Sheet Metal $$(P)$$ Laser Cutting of Sheet Metal $$(LC),$$ Spot Weld...

The tool of an $$NC$$ machine has to move along a circular arc from $$(5,5)$$ to $$(10,10)$$ while performing an operation. The center of the arc is at $$(10,5).$$ Which one of the following $$NC$$ tool path commands per...

During the execution of a CNC part program block $$NO20\,\,\,\,GO2\,\,\,\,X45.0\,\,\,\,Y25.0\,\,\,\,R5.0.$$ The type of tool motion will be

Through holes of $$10$$ $$mm$$ diameter are to be drilled in steel plate of $$20$$ $$mm$$ thickness. Drill spindle speed is $$300$$ $$rpm,$$ feed $$0.2$$ $$mm/rev$$ and drill point angle is $${120^0}.$$ Assuming drill ov...

Quality screw threads are produced by

The time taken to drill a hole though a $$25$$ $$mm$$ thick plate with the drill rotating at $$300$$ $$rpm$$ and moving at a feed rate of $$0.25$$ $$mm$$/revolution is

Machining of complex shapes on $$CNC$$ machines requires

The hardness of a grinding wheel is determined by the

A lead screw with half nuts in a lathe, free to rotate in both directions has

The abrasive material used in grinding wheel selected for grinding of ferrous alloys is

Abrasive material used in grinding wheel selected for grinding ferrous alloys is

In finish machining of an island on a casting with $$CNC$$ milling machine, an end mill with $$10$$ $$mm$$ diameter is employed. The corner points of the island are represented by $$(0,0), (0,30), (50,30)$$ and $$(50,0)$...

A cylinder of $$155$$ $$mm$$ is to be reduced $$150$$ $$mm$$ diameter in one turning cut with a feed of $$0.15$$ $$mm$$/ revolution and a cutting speed of $$150$$ $$m/min$$ on a $$NC$$ lathe. What are the programmed spin...

Helix angle of fast helix drill is normally

In a point to point control $$NC$$ machine, the slides are positioned by an integrally mounted stepper motor drive. If the specification of the motor is $$1$$ deg/pulse, and the pitch of the lead screw is $$3.6$$ $$mm,$$...

Diamond wheels should not be used for grinding steel components

Plain milling of mild steel plates produces

Machine tool, structures are made ................. for high process capability (tough/ rigid/ strong)

Determine the transformation ratio $$(TR)$$ of the gear train connecting the spindle and the lead screw of $$4TPI$$ required to cut $$1.0mm$$ pitch screw threads in a center lathe

Among the conventional machining processes, maximum specific energy is consumed in

A mild steel block of width $$40$$ $$mm$$ is being milled using a straight slab cutter $$70mm$$ diameter with $$30$$teeth. If the cutter rotates at $$40$$$$rpm$$ and the depth of cut is $$2mm,$$ determine the value of ma...

$$CNC$$ machines are more accurate than conventional machines because they have a high resolution encoder and digital readouts for positioning

To get good surface finish on a turned job, one should use a sharp tool with a ......... Feed rate and ............... Speed of rotation of the job.

$$CNC$$ machines are more economical to use even for simple turning jobs.

A grinding wheel $$A$$ $$27$$ $$K7$$ $$V$$ is specified for finish grinding of a $$HSS$$ cutting tool. What do you understand about the wheel from the above code. Is this an appropriate choice?

A milling cutter having $$8$$ teeth is rotating at $$150$$ $$rpm.$$ If the feed per tooth is $$0.1$$ $$mm,$$ the speed in $$mm$$ per minute is

With reference to $$NC$$ machines, which of the following statements is wrong?

In horizontal milling process ............................ (up/down) milling provides better surface finish and .............................. Up/down ) milling provide longer tool life.

In $$PTP$$ type of $$NC$$ system

A milling cutter having $$10$$ teeth is rotating at $$100$$$$rpm$$. The table feed is set at $$50mm$$ per minute. The feed per tooth in $$mm$$ is

Numerically controlled machine tools are better suited for .................. (batch/mass) production, because their setup time is ......... (larger / smaller) in comparison to special purpose machine tools.

For cutting double start screw threads of pitch $$1.0$$ $$mm$$ on a lathe, the thread cutting tool should have a feed rate of

If the longitudinal feed in center-less grinding is expressed by $${V_f} = \pi \,D.\,\,N\,\sin \,\alpha ,\,\,D$$ stands for

In small lot production for machining $$T-$$slots on machine tables, it is expected to use

In $$NC$$ part programming spindle speed of $$730rpm$$ will be coded by the magic - $$3$$ rule as

Gear hobbing produces more accurate gears than milling because in hobbing

Teeth of internal spur gears can be accurately cut in a

In turning operation the feed rate could be doubled to increase the metal removal rate To keep the same level of surface finish, the nose radius of the tool has to be

Minimum dimensional and form accuracy can be obtained in the cylinder bores of automobile engines if the bores are finished by

Cutting speed in grinding is set to a high value to

The standard specification of a grinding wheel is $$A-46-M-6-V-21.$$ It means a wheel of

In twist drills ......... (small/large) point angle and ........ (small/large) helix angle are provided for drilling soft, low strength steel.