Q.1

The wall thickness of thin cylindrical shell with hemispherical ends is __________ that of the spherical ends.

  • equal to
  • more than
  • less than
  • either (b) or (c); depends on maximum permissible internal pressure
Q.2

Typical static submergence for bubble cap plate column operating at atmospheric pressure may be around

  • 2.5"
  • 0.5"
  • 5"
  • 50% of the plate spacing
Q.3

In packed absorption tower, onset of flooding usually occurs at a pressure drop of about __________ mm of water column per metre height of packing.

  • 25-50
  • 50-75
  • 200-250
  • 750-1000
Q.4

For identical situation, condensing film coefficient in case of a horizontal condenser is almost __________ the value expected in case of vertical condenser.

  • half
  • twice
  • thrice
  • five times
Q.5

Column support for the roof of cylindrical storage tank must be provided for

  • small diameter tanks.
  • large diameter tanks.
  • small diameter tall tanks.
  • all tanks irrespective of their heights and diameters.
Q.6

Pick out the wrong statement pertaining to the design of a long tube vertical evaporator.

  • Tube dia is 3-6 cms, while tube length in 3-6 metres.
  • Steam is fed to the shell, whereas the liquor is filled inside the tube.
  • Liquor level is maintained at l/3rd to 1/2 of the height of the tube.
  • none of these.
Q.7

Cylindrical storage tanks used for the storage of volatile liquids (e.g., naphtha) have __________ roofs.

  • conical
  • flat
  • floating
  • fixed
Q.8

The wall thickness for a large high pressure pipeline is determined by the consideration of the

  • axial tensile stress in the pipe.
  • forces exerted by static and dynamic action at bends.
  • circumferential pipewall tension.
  • temperature stresses.
Q.9

The safe height (h) to diameter (d) ratio (i.e., h/d) for liquid/petro fuel storage tank of capacity more thankilolitres is less than

  • 1
  • 2
  • 3
  • 3.5
Q.10

The equivalent diameter for fluid flow through a channel of constant non-circular cross section of area 'A' is given by (where, P = perimeter of the channel in contact with the fluid)

  • 4 A/P
  • A/P
  • 4 P/A
  • A
Q.11

Corrosion allowance in the design of pressure vessel/chemical equipment is not necessary, if

  • plain carbon steel and cast iron parts are used.
  • wall thickness is > 30 mm.
  • material of construction is high alloy steel.
  • both(b) & (c).
Q.12

For a given design of bubble cap, the number of bubble caps to be used per tray is set by the

  • allowable gas velocity through the slots.
  • plate spacing.
  • diameter of the column.
  • all (a), (b) and (c).
Q.13

Baffle width is normally taken as __________ times the tank diameter.

  • 0.1-0.12
  • 0.4-0.5
  • 0.45-0.6
  • 0.2-0.45
Q.14

The distance between the top of the slots and the liquid surface when the static liquid is just ready to flow over the overflow weir is called

  • downcomer liquid seal
  • static submergence
  • skirt clearance
  • none of these
Q.15

Equivalent diameter for heat transfer calculation for a duct of square cross-section having each side as 'd' will be

  • d
  • d
  • 2πd
  • 2d
Q.16

Reflux ratio variation in a distillation column is between

  • zero and infinity
  • zero and one
  • minimum and infinity
  • none of these
Q.17

Height of the flights in the rotary drier is in the range of

  • 0.08 to 0.12 d
  • 0.02 to 0.05 d
  • 0.2 to 0.5 d
  • 0.5 to 0.6 d
Q.18

Pick out the wrong statement.

  • Rivetting provides a permanent fastening method.
  • The joint made by overlapping of one plate over the other, and then rivetting the two plates together with two rows of rivets is called 'double rivetted butt joint'.
  • Shank diameter of the rivets should be less than the size of the hole drilled in the plate for rivetting.
  • The efficiency of a rivetted joint is the ratio of the strength of the rivetted joint to the strength of the solid plate.
Q.19

For turbine agitator, the impeller diameter is about

  • 0.3 to 0.5 d
  • 0.1 to 0.2 d
  • 0.65 to 0.85 d
  • 0.95 d
Q.20

In case of 1.heat exchanger tubes, the inside flow area __________ with decrease in BWG.

  • increases
  • decreases
  • remains same
  • none of these
Q.21

For pipe flows, head is proportional to __________ at constant capacity (where D = pipe diameter ).

  • 1/D
  • 1/D2
  • 1/D5
  • D2
Q.22

Diameter of rivet hole (d, mm) and the plate thickness (t, mm) are related by Unwin's formula as

  • d = 1.1 t
  • d = 1.6 t
  • d = 1.5 t
  • 3t
Q.23

For a cylinderical internally pressurised vessel, which of the following closure types would withstand highest pressure, if each closure is of the same material and thickness ?

  • hemispherical
  • ellipsoidal (2 : 1)
  • conical
  • flat plate
Q.24

Which of the following is the most common type of baffle used in industrial shell and tube heat exchanger ?

  • 75% cut segmental baffle.
  • 25% cut segmental baffle.
  • Orifice baffle.
  • Disk and doughnut baffle.
Q.25

Larger depth of liquid on the trays of a distillation column

  • leads to high tray efficiency.
  • results in higher pressure drop per tray.
  • both (a) & (b).
  • neither (a) or (b).
Q.26

In the case of a shell and tube heat exchanger, the logarithmic mean temperature difference

  • is always less than arithmetic average value.
  • is always more than arithmetic mean value and the geometric mean value.
  • is always less than arithmetic mean value, but more than geometric mean value.
  • may be either more or less than geometric mean and arithmetic mean value depending upon whether the flow of stream is co-current or counter-current.
Q.27

For given number of passes, pitch & tube diameter, the maximum number of tubes that can be accommodated in a shell of tripled inside diameter will be __________ times.

  • about 9
  • considerably more than 9
  • considerably less than 9
  • about 3
Q.28

Fouling factor must be included in the calculation of over all design heat transfer coefficient, when the liquid

  • containing suspended solids flows at low velocity.
  • containing suspended solids flows at high velocity.
  • is highly viscous.
  • is of high specific gravity.
Q.29

The shell side pressure drop in a shell and tube heat exchanger is maximum for __________ baffle.

  • disk and ring
  • segmental
  • orifice
  • independent of the type of
Q.30

A cylinderical pressure vessel of volume 6 πm3 has to be designed to withstand a maximum internal pressure ofatm. The allowable design stress of the material is 125N/mm2 and corrosion allowance is 2 mm. The thickness of the vessel for a length/diameter ratio of 3 will be close to

  • 5 mm
  • 6 mm
  • 8 mm
  • 10 mm
Q.31

Liquid gradient over the tray results due to the

  • resistance offered to flow of liquids by caps & risers and the flow of gas.
  • low gas velocity.
  • large plate spacing.
  • large reflux ratio.
Q.32

Vapor velocity in a distillation column for non-foaming mixture is in the range of __________ times the flooding velocity.

  • 0.1 to 0.3
  • 0.6 to 0.7
  • 0.85 to 0.95
  • 1.5 to 2
Q.33

The force due to wind load acting on a tall vessel depends upon its

  • shape.
  • outside diameter.
  • height.
  • all (a), (b) & (c).
Q.34

Cylindrical pressure vessels in horizontal condition is generally supported on a __________ support.

  • lug
  • skirt
  • saddle
  • guy wire
Q.35

Optimum economic pipe diameter for fluid flow is determined by the

  • viscosity of the fluid.
  • density of the fluid.
  • total cost considerations (pumping cost plus fixed cost of the pipe).
  • none of these.
Q.36

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.

  • two
  • five
  • ten
  • twenty
Q.37

A binary liquid azeotropic mixture has boiling point lower than either of the components, when it shows __________ deviation from Raoult's Law.

  • positive
  • negative
  • no
  • none of these
Q.38

What is the minimum recommended ligament for square pitch arrangement in case of heat exchangers ?

  • 6.5 cms
  • 6.5 mm
  • Equal to tube I.D
  • Equal to tube O.D
Q.39

Pick out the wrong statement.

  • Plate efficiency increases with increase in superficial vapour velocity till entrainment limit.
  • Increase in depth of the liquid about the slots increases the plate efficiency, particularly if the liquid depth is < 1".
  • Too small a plate spacing can cause a low efficiency, if the vapour velocity is greater than the allowable value.
  • none of these.
Q.40

Skirt support is the most suitable for supporting __________ vessels.

  • small horizontal
  • large horizontal
  • tall vertical
  • thick walled
Q.41

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

  • modulus of elasticity
  • modulus of rigidity
  • bulk modulus
  • none of these
Q.42

Lug support is meant for supporting __________ vessels.

  • large horizontal cylindrical
  • tall but empty
  • small
  • thick walled tall
Q.43

The function of manholes provided in the shell of a distillation column is to

  • keep a check on the liquid gradient over the plate by direct visual observation.
  • give access to the individual trays for cleaning, maintenance and installation.
  • guard against foaming & entrainment by dumping antifoaming agent through it.
  • all (a), (b) and (c).
Q.44

Which of the following packing materials provides for maximum mass transfer ?

  • Lessig rings.
  • Raschig rings.
  • Cross-partition rings.
  • All give the same value.
Q.45

The centre to centre distance between two consecutive baffles in a shell and tube heat exchanger is called the baffle pitch or baffle spacing, which is more than 1/5th the I.D. of the shell. Which of the following is not a function of the baffles ?

  • To increase the residence time of shell side fluid.
  • To provide support to the tube bundle.
  • To reduce the induced vibration in the tubes.
  • To increase the tube side heat transfer co-efficient by inducing turbulence.
Q.46

Vapor velocity in a distillation column for non-foaming mixture is in the range of __________ times the flooding velocity.

  • 0.1 to 0.3
  • 0.6 to 0.7
  • 0.85 to 0.95
  • 1.5 to 2
Q.47

Bubble cap diameter used for the distillation column having diameter ranging from 1.5 to 4.5 metres is about __________ mm.

  • 10
  • 50
  • 100
  • 150
Q.48

If a single tube pass heat exchanger is converted to two passes; for the same flow rate, the pressure drop per unit length in tube side will __________ times.

  • increase by 1.8
  • decrease by 22
  • increase by 21.6
  • none of these
Q.49

Pressure drop per tray in the atmospheric distillation column is about __________ psi.

  • 0.01 - 0.5
  • 0.07 - 0.12
  • 0.5 - 1.0
  • 1 - 3
Q.50

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

  • 50 to 100
  • 100 to 150
  • 250 to 500
  • 600 to 700
0 h : 0 m : 1 s