GATE PI 1992
Paper was held on Thu, Jan 1, 1970 12:00 AM
Practice Questions
1
The primary function of a riser is to
2
Investment casting uses ...... A........... as pattern material and is preferred for small parts with .......... B.........designs.

A. wax / resin coated sand
B. simple / intricate

3
Chaplets are placed between mold in order to
4
Investment casting uses ......... (wax / resin coated sand) as pattern material and is preferred for small parts with ................. (simple/intricate) designs
5
If the freezing ratio equal to (casting area/casting volume)/(riser area/riser volume) & the volumetric ratio equal to riser volume/casting volume, for a disc casting of $$20cm$$ diameter and $$10$$ $$cm$$ thick are $$1.4$$ and $$0.8$$ respectively. The corresponding values for a square disc of $$20$$ $$cm$$ side and $$10$$ $$cm$$ thick if the same cylindrical riser with a height to diameter ratio of unity is used in both cases.
6
Match the application with type of pattern GATE PI 1992 Casting - Casting Process Question 9 English
7
Increase in carbon content in plain carbon steels raise its
8
The type of coated electrode most widely used for welding low carbon steel is
9
Filler material is ......... A...... in resistance welding and the heat generated in the process is directly proportional to ........ B.........

(A). used / not used$$\,\,\,\,\,\,\,\,\,$$ $$\,\,\,\,\,\,\,\,\,$$ (B). square of the current / cube of the current

10
The joint configuration best suited for adhesive bonding is
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GATE PI 1992 Joining of Materials - Welding Question 37 English
12
Two sheets of low carbon steel $$1.5mm$$ thick each are spot welded by passing a current $$10000$$ amps for $$5$$ cycles in $$50$$ $$Hz$$ main supply.

i) What is the heat generated due to the supply of power if effective resistance has $$200$$ micro ohms,

ii) The maximum indentation is $$10\% $$ of sheet thickness and density of the spot weld nugget $$8$$ $$gm/cc.$$ If $$1380$$ Joules are required to melt $$1gm$$ of steel, determine heat required for welding operation if $$D=6SQRT$$ $$(t)$$ to determine nugget diameter $$D$$ and assume the nugget size to be equal to metal between the two electrodes

13
In $$MIG$$ welding the power source characteristics is $${V_p} = 36 - {\rm I}/60$$ and the arc characteristics is $${V_a} = 2{L_a}\,\,\,\, + 27.$$ Find the change in power of the arc if the arc length changed from $$2mm$$ to $$4mm.$$ If the maximum current capacity of the power source is $$300$$ Amps, the maximum arc length sustainable is
14
A blind hole is better tapped with a tap having
15
Find the speed range ratio for the drilling machine spindle if the minimum and maximum diameters of drills used are $$5$$ $$mm$$ and $$25$$ $$mm$$ respectively and if the machinability indices for the work materials are $$120$$ (brass) and $$40$$ (alloy steel)
16
If the index crank of a dividing head is turned through one complete revoluation and $$10$$ holes in a $$30$$ hole circle plate, the work piece turns through (in degrees)
17
In a grinding wheel marked with $$AA-48-L-7-V-25, L$$ refers to
18
Control of group of $$NC$$ machines by a supervisory computer is known as ............... control.
19
The component development and manufacturing activities when assisted by a computer are: Computer Aided Graphics $$(CAG), CAD, CAM, CAPP$$ and Computer Aided Quality Control $$(CAQC).$$ The most appropriate sequence of these activities is
20
A $$DC$$ servomotor is directly driving an $$NC$$ table. The pitch of the lead screw of the table is $$5$$ $$mm.$$ The motor rotates at $$100$$ $$rpm$$ for an applied voltage of $$10V.$$ If the voltage speed characteristic of the motor is linear, the applied voltage for a table of $$3m/min$$ is equal to:
21
In metal cutting with a carbide tool, at the maximum recommended speed, the largest $$\% $$ of heat generated goes to the
22
A generalized tool life equation for carbide tool for machining steel is given by
$$\,\,\,\,\,\,\,\,\,\,$$$$\,\,\,\,$$ $$V{T^a}{F^b}{D^c} = K,$$
Where $$V=$$ Cutting speed, meters/min,
$$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$T=$$ Tool life,
$$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$F=$$ feed, $$mm/rev,$$
$$D=$$ depth of cut in $$mm,$$ Indicates have magnitude $$a=0.3, b=0.3, c=0.15,$$

If the feed is halved and depth of cut doubled, for identical tool life of $$60$$ minutes, the percentage change in speed

23
A generalized tool life equation for carbide tool for machining steel is given by
$$\,\,\,\,\,\,\,\,\,\,$$$$\,\,\,\,$$ $$V{T^a}{F^b}{D^c} = K,$$
Where $$V=$$ Cutting speed, meters/min,
$$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$T=$$ Tool life,
$$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$F=$$ feed, $$mm/rev,$$
$$D=$$ depth of cut in $$mm,$$ Indicates have magnitude $$a=0.3, b=0.3, c=0.15,$$

The change in productivity for the new processing conditions

24
Wall thickness of drawn cup is controlled by
25
A hemispherical cup of radius $$'R'$$ is formed in a press working operation. The radius of blank would be
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GATE PI 1992 Metal Forming - Metal Forming Process Question 35 English
27
Thread rolling is restricted to
28
If the elongation factor during rolling of an ingot is $$1.22.$$ The minimum number of passes needed to produce a section $$250 \times 250\,\,mm$$ from an ingot of $$750 \times 750\,\,mm$$ are
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To stress relive a cold worked steel part, it is heated to a temp close to ..... A....... and grains obtained after cooling are........ B.........
A. Lower critical temp/ upper critical temp
B. Fine / coarser
30
In an interference microscope, a groove produces a band distortion of $$4$$ band spacing. If the wave length of the monochromatic light source is $$0.5microns,$$ the groove depth is ......................$$mm$$
31
In mass manufacturing, two holes in a plate type of component are ideally located with the help of
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The fit on a hole-shaft pair system is specified as $$H7$$-$$s6$$. The type of fit is
33
The diameter of the best wire to measure the effective diameter of a metric screw threads of $$0.5$$ $$mm$$ pitch is ......... $$mm$$
34
The most widely used reinforcement in modern day $$FRP$$ tennis racket is
35
A straight edge is inspected on a coordinate measuring machine. The readings obtained at intervals of $$100mm$$ along the top edge are $$100.01, 100.05, $$ and $$100.04$$ $$mm$$ the straightness error, making the end points as reference, is ....... $$mm$$
36
A shaft of diameter $${20^{\matrix{ { + 0.05} \cr { - 0.15} \cr } }}$$ and a hole of diameter $${20^{\matrix{ { + 0.20} \cr { + 0.10} \cr } }}\,\,mm$$ when assembled would yield.
37
The skid in a stylus type roughness measuring instrument is used to provide ............ A .............. and define ................... B .............. geometrical profile of the surface.

$$A.$$ support / datum
$$B.$$ micro / macro

38
Powder metallurgical components have
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$$A$$ $$30$$ $$mm$$ hole shaft assembly results in minimum and maximum clearances of $$0.03$$ $$mm$$ and $$0.30$$ $$mm$$ respectively. The hole has a unilateral tolerance with zero fundamental deviation. If the tolerance on the shaft is $$0.08$$ $$mm,$$ the maximum size of the hole is
40
To obtain dimension of $$61.18$$ $$mm$$ using slip gages, the most appropriate combination is