93089-3746-cncquesbank.doc

8/11/2019 93089-3746-CNCQuesBank.doc

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PART - B

1. State the right hand rule of co-ordinate system in NC machine.2. Ho many a!es are a"aila#le in a hori$ontal machining centre

%. Ho many a!es are a"aila#le in a "ertical machining centre

&. 'hy do e go in for #all scre ty(e for linear tra"el in CNC lathe)*. 'hat ty(e of slide ay is used in (rototy(e and (roduction machine) 'hy)

+. 'hat is meant #y format of a NC (rogram)

,. Ho many a!es are a"aila#le in a ire cut CNC /)0. Name any four CA/ (acages used for com(uter aided (art (rogramming.

. efine (reset tooling.

13. 'hat cutting tool materials are used in CNC machines)

11. State any four as(ects regarding maintenance of CNC machines.12. 4s it ire to re(lace a turret lathe #y CNC lathe in a 5o# (roduction unit) 'hy)

1%. 'hat (roduction en"ironment re6uires CNC machines)

1&. 'hat are the ad"antages of CNC com(ared to NC)

1*. 'rite short notes on recirculating roller (acs.1+. 'hat are the im(ortant re6uirements of a CNC machine s(indle)

1,. 7ist out any four CNC inter(olation methods.10. 'hat is tool (reset)

1. 'hat is a (art (rogram)

23. !(lain circular (oceting ith an e!am(le.21. 'hat are the as(ects considered hile selecting a (articular CNC machine from a

ide "ariety of a"aila#le CNC machines)

22. 'hat are the actions taen #efore introducing CNC machines in an industry)

2%. istinguish #eteen NC and CNC machines.2&. 'hat is the ad"antage of antifriction guide ays)

2*. 'hat is #all scre) 'here is it used in CNC machines)2+. 'hat is digital read out 8R9:)2,. 'hat are the feed #ac de"ices used in CNC machines)

20. 'hat is re(eata#ility)

2. 'hat is cutter diameter com(ensation)%3. Ho does cutter diameter com(ensation differ from tool length offset)

%1. State the ground rules to #e folloed hile formulating APT geometry statement.

%2. 'hat are the (ractical constraints to introduce CNC machines in industries)

%%. 'hat are the o"erhead costs incurred on o(eration of CNC machines)%&. State the o"erall oring (rinci(le of CNC machines.

%*. 'hat are the im(ortant features of machining centers)

%+. 'hat are the control as(ects in contour system)%,. Ho is (osition control achie"ed in CNC machines)

%0. !(lain (ost (rocessor statements in APT (rogramming.

%. 7ist out the "arious ord addresses in NC (rograms.&3. 'hat are 6ualified tools in NC machines)

&1. 'rite a#out cermets and their a((lication.

&2. 7ist out any ;9<R factors influencing the selection of CNC machines.

&%. 'hat is condition monitoring in CNC machines)

8/11/2019 93089-3746-CNCQuesBank.doc


&&. 'rite the ty(es of co = ordinate system

&*. 7ist the merits of CNC machines

&+. 'hat are the ad"antages of AC ser"o motors)&,. efine (reloading of #all scres

&0. efine machine datum

&. State the oring (rinci(le of CNC lathe.*3. 'hat are the main ad"antages of machining centers)

*1. Ho is "elocity control achie"ed in CNC systems)

*2. 'hat is the role of a counter in (osition control mechanism of a CNC system)*%. State the Right Hand rule of co ordinate system in NC systems.

*&. 'hat are /achining centers)

**. 'hat are the to ty(es of NC systems)

*+. efine NC and CNC.*,. State TR< or ;A7S and 5ustify your anser. Point to (oint control system can

#e effecti"ely used in CNC turning centre.

*0. 'hat is meant #y (reloading of #all scre)

*. State the re6uirements of s(indle dri"es for CNC machine tools.+3. 7ist out any four CNC inter(olation methods

+1. Ho do you sense the direction of mo"ement of slide hile using grating ty(etransducer)

+2. 'hat is cutter radius com(ensation)

+%. Ho the cutter radius com(ensation (rogrammed)+&. State the functions of the folloing > and / codes

>31 >33 >3 >1,

+*. Ho is non-cutting times reduced in CNC machines)

++. State the "arious eely acti"ities to #e (erformed in the (re"enti"e maintenanceof CNC machine tools.

+,. 'hat is the difference #eteen (oint-to-(oint and continuous (ath systems)

+0. 'hat are the four ty(es of dri"e motors used on numerical control machines)+. 'hat is loo( system)

,3. 'hat is the difference #eteen o(en and closed loo( system)

,1. 'hy is the choice of loo( system im(ortant),2. 'hat is a numerical control machine)

,%. 'hat is the difference #eteen an NC ta(e machine and a CNC machine)

,&. 'hat is direct numerical control)

,*. 'hat is distri#uti"e numerical control),+. Name four ays to enter a (rogram into a com(uter numerical control machine.

,,. 'hat are the fi"e ma5or o#5ecti"es of numerical control)

,0. 'hat is a machine a!is),. 'hat are the to ty(es of (ositioning systems) 'hat are the differences #eteen

them)

03. 'hat machine feature determines the (ositi"e or negati"e direction.01. 'hat is (rocess (lanning)

02. 7ist three factors used #y the (rogrammer in deciding ho to hold a or(iece.

0%. 7ist three factors that determine the tool selection.

0&. >i"e the ad"antage of car#ide tools.

8/11/2019 93089-3746-CNCQuesBank.doc


0*. 9n hat ty(e of materials are ceramic inserts used)

0+. 'hat ty(es of tools are (referred for NC use)

0,. 'hat are the four common hole o(erations (erformed on NC machines)00. 'hat is the cutting s(eed) 4s it the same as the s(indle r(m)

0. 'hy is tool changing so im(ortant in numerical control)

3. 'hat are the to ty(es of tool changes)1. 'hat are the fi"e #asic ty(es of tool changer)

2. 'hat is a tool register)

%. 'hat is a (re(aratory function)&. 'hat are miscellaneous functions)

*. 'hat code is used to initiate linear inter(olation)

+. 'hat is the format for circular inter(olation using the arc "ector method)

,. 'hat is the format for circular inter(olation using the radius method)0. 'hat is ram( on mo"e) 'hen does it occur)

. 'hat is ram( off mo"e) 'hen does it occur)

133. 'hat cautions must #e o#ser"ed hen instituting cutter com(ensation

inside a (ocet)131. 'hat do the codes >&3? >&1 and >&2 do)

132. 'hat cautions must #e o#ser"ed hen instituting cutter com(ensationhen milling angles)

13%. 'hat is a do loo()

13&. 'hat is the format for a su#(rogram call)13*. 'hat is the format for a do loo()

13+. 'hat does com(uter aided (rogramming allos the (rogrammer to do)

13,. 'hat are the #asic (arts of a com(uter aided (rogramming system)

130. escri#e ho an APT (rogram generates an NC (rogram.13. Ho does a solid modeling system different from a CA@CA/ system)

113 /ae neat setches of a ty(ical turning centre? hori$ontal machining centre andindicate (rimary !? y? $ a!es of motion.

111 istinguish #eteen CNC Punching and Ni##ling /achine.

'hat is meant #y (re-loading of #allscre) 112.State true or false. ustify your anser. Ste((er motor can #e used as dri"e for

closed loo( control system.

11& Ho are non-cutting times reduced in CNC /achine) Name and descri#e #riefly the to accessories hich mae machining centres

"ersatile.

11* 'hat is cutter diameter com(ensation) Ho does it differ from tool length

offset)11+ State the ground rule to #e folloed hile formulating APT geometry statement.

11, Briefly e!(lain 4S9 >RA4N> classification for sintered car#ides)

11.0 State any & features that an ideal oring holding de"ice ould (asses for CNCa((lications.

113'hat is the ad"antage of antifriction guide ays)

111. Name any four CA/ (acages used for com(uter aided (art (rogramming.

8/11/2019 93089-3746-CNCQuesBank.doc


8/11/2019 93089-3746-CNCQuesBank.doc


22. !(lain the method of storing the tools? tool changing methods and codification

of tools in an ATC.

2%. !(lain the "arious or holding de"ices used for o(erations in"ol"ing rotatingor (iece and those for fi!ed or (ieces.

2&. !(lain ho to select and a((ly #readon and (re"enti"e maintenance for a

trainer model CNC lathe.2*. Briefly e!(lain onD 8i: /achine diagnostics 8ii: ;actors influencing introduction

of CNC machine.

2+. numerate different ty(es of CNC motion control systems.2,. escri#e the features of CNC grinding machine.

20. escri#e the features of "ertical machining centre.

2. escri#e the features of CNC / ire cut machine.

%3. 7ist out the "arious ty(es of antifriction guide ays used in CNC slides.escri#e any one antifriction guide ay.

%1. 'hat are the feed dri"es commonly used in CNC machine tools) escri#e the

oring (rinci(le? ad"antage and limitations of any one.

%2. iscuss the "arious ste(s in"ol"ed in retrofitting of a lathe.%%. !(lain ith schematic diagram the constructions and o(eration of the dou#le

gri((ing system of tool changing system.%&. escri#e ith neat setches the oring (rinci(le and ad"antages of the

folloingD 8i: ncoder 8ii: linear inductosyn.

%*. !(lain the terms?E6ualifiedE? and F(reset-toolingE in the conte!t of CNCtooling.

%+. escri#e ith neat setches the oring (rinci(le of the folloing orholding

de"ices for CNC a((licationD Collets G machine "ices.

%,. escri#e ith neat #loc the "arious ste(s in Com(uter Assisted PartProgramming 8CAPP:.

%0. numerate APT geometry and motion statements.

%. 7ist out the "arious factors influencing the selection of CNC machines. !(lainany se"en factors.

&3. numerate the "arious ste(s in (re"enti"e maintenance of CNC machine tools.

&1. Present a classification of CNC machines.&2. escri#e the s(indle #earing in a CNC machine tool.

&%. 'hat are the criteria to #e considered hile selecting the AC dri"e for a CNC

machine)

&&. escri#e the dou#le gri((ing system of tool changing in a CNC machine.&*. >i"e the S(ecification of a ty(ical CNC chucer.

&+. !(lain ith neat setch the oring of a rotary encoder.

&,. !(lain ith neat setch the oring of a Synchros and Synchro-resol"ers.&0. !(lain ith neat setch the oring of a incremental linear transducer.

&. !(lain ith neat setch the oring of a inductosyn.

*3. iscuss the modules a"aila#le in CA/ softare.

*1. 8a: 8i: !(lain the oring (rinci(le of CNC system

8ii: iscuss the (rinci(le of NC.

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*2. !(lain the oring of ada(ti"e control system and rite its ty(es

*%. !(lain any to feed#ac de"ices ith neat setch.

*&. 8i: iscuss the a!es feed dri"es 8ii: 'rite on the re6uirements of a good slide ay system

**. !(lain the oring (rinci(le of the to ty(es of ada(ti"e control systems.

*+. 4dentify and #riefly e!(lain a#out the /echatronics as(ects in"ol"ed in thefolloing machine toolsD

8i: rilling machine

8ii: Boring machine8iii: >rinding machine

8i": S(ot 'elding machine.

*,!(lain the constructional features of recirculating #all scres. Ho can the

#aclash effect in them #e eliminated)*0. 'hat are ser"o dri"es@ 'rite note on the folloing s(indle dri"es

8i: C motors

8ii: Ste((er motors

8iii: AC motors.*. iscuss the modules a"aila#le in CA/ softare.

%+. escri#e the features of hori$ontal machining centre.

+3.i: >i"e a #rief descri(tion of linear motion elements as used in CNC machine toolslides. 80:

ii: Setch and descri#e the s(eed tor6ue characteristics of a C s(indle motor. 80:

+1.a: State different ty(es of linear measuring transducer that can #e used for (ositional

feed#ac and e!(lain their (rinci(les of o(eration 8any to: 2I82 ! , :

#: escri#e the different ty(es of (re"enti"e maintenance (rograms for CNC machine

tools).%0a:i: !(lain ith neat #loc diagram ty(ical configuration of Ada(ti"e control

machining system. 80:

ii: escri#e the (rinci(le of oring of CNC 7aser Beam /achine. 80:

+2.#:i: escri#e a CNC ire / machine 80:

ii: iscuss ith neat #loc diagram general configuration of a NC system) 80:

+%.a: !(lain the terms (re-set? 6ualified? Semi-6ualified and? inde!a#le insert in

the conte!t of CNC tooling.

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+&.#: escri#e ith neat setches any to or holding de"ices for rotating or(ieces

and any to o holding de"ices for fi!ed or(ieces.

+*a: The com(onent shon in ;ig J 1*a is to #e machined from a lo car#on steel (late

hich is a((ro!imately 2 mm o"ersi$e on the (rofile and has #een (re"iously machined

to (roduce the to locating doel holes? and the clam(ing hole. 4t is held in a fi!turehich locates and clam(s the com(onent rite a (art (rogram using a#solute units to

8i:. /ill the (rofile using a 1+ mm diameter /ill.8ii:. /ill the 13 mm slot.

93089-3746-cncquesbank.doc

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