Plant Design

Question 1

The ratio of shear stress to shear strain is called

A. bulk modulus
B. shear modulus
C. modulus of rigidity
D. modulus of elasticity

Answer 1

B. shear modulus

Question 2

Which of the following material is seldom used for pressure
vessel construction?

A. Rimmed still
B. Mild steel
C. Killed steel
D. Semi killed steel

Answer 2

Rimmed still

Question 3

Fresh
water carrying pipelines in chemical industries are _____ colored with color.

A. sea green
B. brown
C. yellow
D. red

Answer 3

sea green

Question 4

25% cut segmental baffle means that the baffle

A. height is 75% of the I.D. of the shell.
B. height is 25% of the I.D. of the shell.
C. spacing is 75% of its height.
D. width is 25% of its height.

Answer 4

height is 75% of the I.D. of the shell.

Question 5

Liquid/petroleum fuel storage tanks are built underground (as in case of petrol pumps), when the storage capacity is
less than _________ kilolitres

A. 20
B. 30
C. 45
D. 85

Answer 5

45

Question 6

Le/D for fully open globe value may be around

A. 10
B. 25
C. 75
D. 300

Answer 6

300

Question 7

Lug support is
A. the most suitable for thick vertical vessel.
B. same as bracket support.
C. provided usually for vessels of much smaller height than skirt supported vessels.

Answer 7

ALL

Question 8

With increase in the number of shells passes, the value of F T

A. increases
B. decreases
C. remains same
D.remains same, only if the number of tube passes does
not change

Answer 8

INCREASES

Question 9

Holes of a sieve tray are arranged in triangular pitch ______
times the hole diameter.

A. 1.5 to 2
B. 2.5 to 5
C. 5 to 10
D. 10 to 15

Answer 9

2.5 to 5

Question 10

In case of a shell and tube heat exchanger, the minimum shell
thickness for carbon steel (inclusive of corrosion allowance)
depends on shell diameter and is in the range of____ mm

A. 3-5
B. 5-11
C. 8-15
D. 12-18

Answer 10

5-11

Question 11

The stress developed in a material without any permanent set is
called the

A. ultimate stress
B. yield stress
C. elastic limit
D. breaking stress

Answer 11

elastic limit

Question 12

In a shell and tube heat exchanger, the ‘tube pitch’ is defined as
the

A. O.D. of the tube for square pitch.
B. shortest distance between two adjacent tube holes.
C. shortest centre to centre distance between adjacent tubes.
D. none of these.

Answer 12

C. shortest centre to centre distance between adjacent tubes.

Question 13

Which
of the following is not a valid assumption in continuous
binary distillation for calculating the number of equilibrium stages
by Mc Cabe Thiele’s method

A. Sensible heat changes for vapor & liquid are negligibly small.
B. Reflux is not a saturated liquid.
C. Molar latent heat of the two components are equal.
D. Heat of mixing of normal liquid is assumed to be zero

Answer 13

Reflux is not a saturated liquid.

Question 14

In case of bubble cap distillation column of diameter greater than
1.2 m, the cap diameter is roughly ____ about cm.

A. 10
B. 20
C. 30
D. 40

Answer 14

10

Question 15

Tube side pressure drop in a 1-2 heat exchanger (for turbulent flow of fluids through the tubes) is about ____ times, that in a 1 1 heat exchanger having the same size number of tubes
and operated at the same liquid flow rate

Answer 15

8

Question 16

To keep the power input constant for a stirred vessel operating
under fully developed turbulent flow conditions (constant power
number), if the impeller diameter is increased by 20 the
impeller speed should be decreased by a factor of

Answer 16

(1.2)^5/3

Question 17

The value of fouling factor depends upon the
A. characteristic of process fluid.
B. velocity of process fluid containing suspended solids.
C. suspended solids in the fluid.
D. (a), (b) and (c).

Answer 17

D. (a), (b) and (c).

Question 18

Where does the maximum tensile strength occur in a thick
cylindrical vessel subjected to internal pressure?
A. At the inner surface.
B. At the mid thickness of the cylindrical wall.
C. At the outer surface.
D. None of these.

Answer 18

A. At the inner surface.

Question 19

It is not desirable to design a heat exchanger for LMTD
correction factor, FT, of less than
A. 0.99
B. 0.95
C. 0.80
D. 0.55

Answer 19

C. 0.80

Question 20

Arivetted joint does not fail by of rivets.
A. 0.99
B. 0.95
C. 0.80
D. 0.55

Answer 20

D. 0.55

Question 21

Triangular pitch tube layout as compared to square pitch in a
shell and tube heat exchanger
A. permits the use of less tubes in a given shell diameter.
B.facilitates comparatively easier external cleaning because of
large clearance.
C. permits the use of more tubes in a given shell diameter.
D. both (b) and (c)

Answer 21

C. permits the use of more tubes in a given shell diameter

Question 22

Bracket supports are the most suitable for supporting
vessels.
A. thick walled vertical
B. horizontal
C. thin spherical (e.g. Horton sphere)
D. none of these

Answer 22

A. thick walled vertical

Question 23

In a multi-pass shell and tube heat exchanger, the shell side
cross flow area does not depend upon
A. baffle spacing
B. clearance
C. pitch
D. none of these

Answer 23

D. none of these

Question 24

Two iron pipes of the same nominal diameter but different
schedule numbers will have the same
A. inside diameter
B. outside diameter
C. wall thickness
D. none of these

Answer 24

A. inside diameter

Question 25

Lessing ring is formed by the addition of a partition across the centre of a raschig ring, which results in an area increase of about percent. A. 5 B. 20 C. 35 D. 55

Answer 25

20

Question 26

In chemical process equipment, the conical bottom heads used, usually has an apex angle of A. 20° B. 40° C. 60° D. 80

Answer 26

C. 60°

Question 27

Smaller sized packings are generally dumped to the packed columns, and the large ones of size greater than ____ mm are stacked individually, which provides better control over bed porosity and offers lower gas pressure drop. A. 25 B. 50 C. 75 D. 150

Answer 27

C. 75

Question 28

Correct use of 'factor of safety' is very important in equipment design. It is defined as the ratio of the A. ultimate stress to breaking stress. B. ultimate stress to working stress. C. working stress to ultimate stress. D. none of these

Answer 28

B. ultimate stress to working stress

Question 29

The operating velocity in the absorption tower is usually 40-50% of the flooding velocity. Packed absorption towers are normally designed for a pressure drop of about ______ mm of water column per meter height of packing. A. 1-5 B. 20-40 C. 100-150 D. 1000-150

Answer 29

B. 20-40

Question 30

In perforated plate towers, the A. hole sizes may be around 1/8" or 3/16". B.total hole area may be around 6 to 15% of tower crosssectional area. C. pressure drop is less compared is similar bubble cap towers. D. all (a), (b) and (c)

Answer 30

D. all (a), (b) and (c)

Question 31

The ends of a cylindrical vessel can be closed by a head, which can be one of the four shapes. For the same thickness, choose the one which can withstand the highest pressure. A. Flat plate B. Hemispherical C. Torispherical D. Ellipsoidal

Answer 31

D. Ellipsoidal

Question 32

Wall thickness of schedule 40 pipe as compared to that of schedule 80 pipe is A. more B. less C. same D. either (a) or (b); depends upon the I.D. of the pipe

Answer 32

B. less

Question 33

Pick out the wrong statement pertaining to the design of a basket type evaporator. A. It is used for high viscosity liquor having large rate of scaling. B. The tube bundle is suspended on bracket. C. There is no central downtake. D.Downtake is formed by the annular space between the bundle and the shell

Answer 33

A. It is used for high viscosity liquor having large rate of scaling

Question 34

Speed of the drum of the rotary vacuum filter normally ranges from ___ rpm. A. 0.1 to 2 B. 5 to 7 C. 3 to 8 D. 8 to 15

Answer 34

A. 0.1 to 2

Question 35

Astuffing box is used for A.absorbing the contraction/expansion of pipeline due to temperature changes. B. prevention of fluid leakage around moving parts. C. facilitating smooth opening and closing of a valve. D. reducing the resistance of fluid flow

Answer 35

B. prevention of fluid leakage around moving parts.

Question 36

In a heat exchanger, shell side fluid velocity can be changed by changing the tube A. layout B. pitch C. both (a) & (b) D. neither (a) nor (b

Answer 36

C. both (a) & (b)