8/12/2019 ME C342

1/2

BIRLA INSTITUTE OF TECHNOLOGY & SCIENCE, PILANI

First Semester 2006-07Production Techniques (ME C342)

Comprehensive Examination

!"m!r#s$ %0

Open book!te$ 14-12-2006

N'te$ Ass(me s(it!)*e +!*(es i e.ess!r/

Q 1 A cuboid mold of 100 cm side is to be filled by a parting line gate (mid way in one of the

sides) of 10 cm2 !otal height of the sprue is "# cm $etermine the filling time of the mold

neglecting frictional losses %&'

Q 2 A washer haing internal and eternal diameters as #2 mm and "4 mm respectiely is to be

made from a *# mm thic+ steel strip using a r'1ressi+e ie !he cutting is complete at

*0, of the punch trael !he ultimate shear strength of the strip steel is ##0 .mm 2 /ind

the shear to be proided (assume eual shear on both the processes) in order to bring the ob

within the capacity of a 100 + press aailable in the shop %"'

Q * n a wire drawing operation3 initial wire diameter is ## mm and the final wire diameter is #

mm $ie angle is 1403 die land is * mm and the co-efficient of friction is 01# /ind the

drawing load Assume tensile yield strength (y) 5 200 .mm2 %&'

Q 4 !he maimum power capacity of a broaching machine is 1# + 7sing this machine3 a

circular hole of diameter 20 mm in a *0 mm thic+ mild steel plate is to be enlarged to a

diameter of 2# mm A cut per tooth of 00# mm is used and the ra+e angle proided to the

broach teeth is 100 Assuming the co-efficient of friction and shear stress to be 0# and

400.mm2 respectiely3 find out the minimum possible time in which one part can be

machined 7se 8ee9s and :haffer9s shear angle relationship 374

;;;;;;;

1

PART C

1

8/12/2019 ME C342

2/2

BIRLA INSTITUTE OF TECHNOLOGY & SCIENCE, PILANI

First Semester 2006-07Production Techniques (ME C342)

Comprehensive Examination

!"m!r#s$ %0

Cosed book!te$ 14-12-2006

N'te$ Be s(..i.t, ' .reit 5i** )e 1i+e 'r !m)i1('(s !s5ers

St!rt !s5eri1 e!. (esti' ' ! e5 !1e

Q 1

i) hat are the differences between a casting and its pattern other than shrin+age

allowance3 machining allowance and draft< Also3 write the factors which guide us in

deciding a pattern material for a gien ob

ii) $ifferentiate between impregnating and infiltration in powder metallurgy Also3 write

the adantages and applications of both processes

iii) $ifferentiate between true centrifugal and semi centrifugal casting processes

i) $iscuss arious factors which reduce roll separating force in a rolling operation

) rite important process parameters of 7:= process ith the help of suitable figures3

show the effect of these parameters on material remoal rate

i) ith the help of a simple figure3 eplain the wor+ing of a rotational molding process

ii) ith the help of a suitable figure3 eplain the wor+ing of a plasma arc welding of a non-

conducting material

iii) >plain the mechanics of >$= process

%&?*524'

Q 2 $erie a relation of optimum cutting speed for minimum cost for a simple turning

operation Assume constant feed and other releant data for simplicity %6'

;;;;;;;

2

PART B

2