S8

Question 1

Power required for agitation depends upon the

Answer 1

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

Question 2

Tube height in a calendria type evaporator is normally less than ________ metres.

Answer 2

1

Question 3

Pick out the wrong statement.

Answer 3

A reducer is used to change the direction of a pipe in a straight run.

Question 4

For a 25 mm hole drilled in plates to be rivetted, the shank diameter of the rivet should be ________ mm.

Answer 4

23

Question 5

In a shell and tube heat exchanger having square pitch, the shell side equivalent diameter is given by (where, P = pitch, d = outside diameter of the tube)

Answer 5

4 (P^2 - πd^2 / 4) / πd

Question 6

Optimum economic pipe diameter for fluid flow is determined by the

Answer 6

total cost considerations (pumping cost plus fixed cost of the pipe).

Question 7

Pressure differential maintained across a continuous rotary vacuum filter is in the range of ________ mm Hg column.

Answer 7

250 to 500

Question 8

Vertical storage vessels are never supported by ________ support.

Answer 8

saddle

Question 9

In a double pipe (concentric) heat exchanger, the hydraulic radius for heat transfer (for a fluid flowing through the annulus) would be

Answer 9

more than that for fluid flow.

Question 10

Elastic failure of a material occurs, when the tensile stress equals yield strength, yield point or the elastic limit. Also, the elastic failure occurs according to maximum strain theory, when the maximum tensile strain equals (where, σ = yield strength and E = modulus of elasticity)

Answer 10

σ/E

Question 11

In a pressure vessel containing multiple openings of various dimensions at different parts, stress concentration at the edges of the opening is maximum which becomes negligibly small beyond the area covered by ________ times the hole diameter.

Answer 11

two

Question 12

What is the slope of the feed line, if the feed to a distillation column is a saturated liquid?

Answer 12

∞

Question 13

Filtration rate is affected by the

Answer 13

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

Question 14

Liquid gradient over a tray can be minimised by

Answer 14

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

Question 15

In a shell and tube heat exchanger for a given heat transfer surface area, smaller diameter tubes are favoured as compared to larger diameter ones; because the smaller diameter tubes Le/D for 90° elbow (medium radius) and 90°square elbow would be respectively around

Answer 15

can be fitted into a smaller shell diameter hence the cost of the heat exchanger would be less.
25 and 60

Question 16

__________ heat exchanger is also known as ‘hair pin type’ exchanger,

Answer 16

Double pipe

Question 17

What is the value of ‘q’ for saturated vapor feed to a distillation column? (where q = fraction of the feed stream that is liquid.)

Answer 17

0

Question 18

In hydrostatic testing of welded pipe (for leakage, strength etc.) the ratio of minimum hydrostatic test pressure to internal design pressure is around

Answer 18

1.5

Question 19

Frame thickness in the plate and frame filter press is normally in the range of __________ inches.

Answer 19

0.25 to 8

Question 20

Cylinderical shell thickness of rotary drier is generally __________ mm.

Answer 20

6-8

Question 21

The ratio of lateral strain to linear strain is termed as the

Answer 21

Poisson’s ratio

Question 22

The distance between the centre of a rivet hole to the nearest edge of the plate is called

Answer 22

margin

Question 23

Mc Cable Thiele method used for finding theoretical stages in a distillation column assumes that the

Answer 23

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

Question 24

A minimum clearance of about __________ mm is maintained between the distillation column wall and the bubble cap.

Answer 24

38

Question 25

Pick out the wrong statement.

Answer 25

none of these.

Question 26

Pick out the wrong statement pertaining to shell and tube heat exchanger.

Answer 26

Bracket supports are used for horizontal shell, while saddle support is used for vertical shell.

Question 27

Wind load consideration in the design of a support can be neglected, when the vessel is

Answer 27

short (< 2 m) and housed indoor.

Question 28

Souders Brown equation given by, U = Kv sqrt ρl - ρv / ρv , is used for the calculation of the __________ in a continuous distillation column.

Answer 28

diameter of the bubble cap column

Question 29

The ratio of volumes of the mixed reactor to the plug flow reactor (for identical feed composition, flow rate, conversion, and for all positive reaction orders) is always

Answer 29

> 1

Question 30

Le/D for a Tee (used as elbow, entering run) would be around

Answer 30

60

Question 31

Log mean temperature difference in case of multi-pass shell and tube heat exchanger is always

Answer 31

less than arithmetic mean value.

Question 32

Practical dividing line between a ductile and brittle materials is suggested, when the ultimate elongation is about 5%. Generally, larger the knuckle radius, stronger is the corner torus section of a head. The knuckle radius provided should be less than __________ of the head.

Answer 32

either (a) or (b), whichever is larger

Question 33

Tubes are fixed to the tube sheet (a thick circular metallic plate) by the method of tube rolling and brazing (non-removable) or ferrule connection (removable). Thickness of the tube, sheet is normally __________ the outside diameter of the tube but in no case it should be less than 22 mm (7/8”).

Answer 33

equal to

Question 34

A shell may by termed as thin if its thickness to diameter ratio is less than 0.1. The factor which can be neglected in the calculation of membrane stresses is

Answer 34

bending

Question 35

Scale up problem in design based on the similarity concept takes into account __________ similarity.

Answer 35

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

Question 36

__________ closure is the weakest enclosure for cylindrical vessels.

Answer 36

Conical or flat plate

Question 37

Which of the following efficiencies can be greater than 100%?

Answer 37

Murphree plate efficiency.