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Question 1

Fresh water carrying pipelines in chemical industries are coloured with ________ color.

Answer 1

sea green

Question 2

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

Answer 2

Rimmed still

Question 3

The ratio of shear stress to shear strain is called

Answer 3

shear modulus

Question 4

25 per cent cut segmental baffle means that the baffle

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.

Answer 5

45

Question 6

Le/D for fully open globe value may be around

Answer 6

300

Question 7

Lug support is

Answer 7

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

Question 8

Pick out the wrong statement pertaining to the use of valve tray, seive tray and bubble cap trays in continuous distillation column.

Answer 8

Maintenance cost for valve and seive trays are comparatively more than bubble cap tray due to their relatively complicated construction features.

Question 9

With increase in the number of shell passes, the value of FT

Answer 9

increases

Question 10

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

Answer 10

2.5 to 5

Question 11

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.

Answer 11

5-11

Question 12

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

Answer 12

elastic limit

Question 13

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

Answer 13

shortest centre to centre distance between adjacent tubes.

Question 14

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?

Answer 14

Reflux is not a saturated liquid.

Question 15

Overall distillation column efficiency for most of the refinery columns can be given by (for μ = 0.07 - 1.4 cp and relative volatility < 4) (where η = overall column efficiency, % μ = molal average viscosity of feed at average column temperature and pressure, cp Δp = pressure drop per tray, psi)

Answer 15

η = 17 - 61.1 log μ

Question 16

The value of fouling factor depends upon the

Answer 16

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

Question 17

In case of bubble cap distillation column of diameter greater than 1.2 metres, the cap diameter is roughly about ________ cms.

Answer 17

10

Question 18

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 18

8

Question 19

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 19

(1.2)^5/3

Question 20

Where does the maximum tensile strength occur in a thick cylindrical vessel subjected to internal pressure?

Answer 20

At the inner surface.

Question 21

It is not desirable to design a heat exchanger for LMTD correction factor, FT, of less than

Answer 21

0.80

Question 22

A rivetted joint does not fail by __________ of rivets.

Answer 22

none of these

Question 23

Triangular pitch tube layout as compared to square pitch in a shell and tube heat exchanger

Answer 23

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

Question 24

Bracket supports are the most suitable for supporting ________ vessels.

Answer 24

thick walled vertical

Question 25

In a multipass shell and tube heat exchanger, the **shell side cross flow area does not depend upon**

Answer 25

**none of these**

Question 26

Two iron pipes of the **same nominal diameter** but **different schedule numbers** will have the **same**

Answer 26

**inside diameter**

Question 27

**Steam side heat transfer co-efficient** for design consideration under **ordinary condition** can be assumed to be **about** ________ **kcal/hr.m2.°C.**

Answer 27

**7500**

Question 28

**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.**

Answer 28

**20**

Question 29

In chemical process equipments, the **conical bottom heads** used, usually has an **apex angle** of

Answer 29

**60°**

Question 30

**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.

Answer 30

**75**

Question 31

**Shell side heat transfer co-efficient** in case of **square pitch** as **compared** to the **triangular pitch** under **similar condition** of fluid flow and tube size is

Answer 31

**less**

Question 32

Correct use of '**factor of safety**' is very important in equipment design. It is defined as the **ratio of the**

Answer 32

**ultimate stress to working stress.**

Question 33

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 metre height of packing.

Answer 33

**20-40**

Question 34

________ **tray arrangement** is recommended for distillation column having **diameter upto 4 ft**.

Answer 34

**Cross flow**

Question 35

What is the value of '**q**' for **saturated liquid feed** to a distillation column?

Answer 35

**1**

Question 36

In **perforated plate towers**, the

Answer 36

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

Question 37

The **main purpose** of providing **stepping on the trays** is to

Answer 37

**facilitate handling of large flow rate of liquid.**

Question 38

The **operating pressure drop range** in a **bag filter** is about ________ **mm water gauge.**

Answer 38

**50-150**

Question 39

The ends of a cylinderical 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**.

Answer 39

**Ellipsoidal**

Question 40

For **laminar flow (NRe < 2100)** in steel pipe, the **optimum inside pipe diameter** is given by

Answer 40

**Di, opt = 3 Q^0.36 ρ^0.18**

Question 41

Pick out the **correct statement**.

Answer 41

**Packed towers are generally preferred over plate towers, if the liquids have a *foaming tendency*.**

Question 42

Wall thickness of schedule 40 pipe as **compared** to that of **schedule 80 pipe is**

Answer 42

**less**

Question 43

Pick out the **wrong statement** pertaining to the design of a **basket type evaporator.**

Answer 43

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

Question 44

Pick out the **wrong statement** pertaining to the **design of the bubble cap tray** of a distillation column to give stable operation and even vapour distribution.

Answer 44

**none of these.**

Question 45

**Speed of the drum of the rotary vacuum filter** normally **ranges** from __________ rpm.

Answer 45

**0.1 to 2**

Question 46

A **stuffing box** is used for

Answer 46

**prevention of fluid leakage around moving parts.**

Question 47

Pressure drop (**Δp**) and the superficial gas mass velocity (**G**) in case of packed absorption tower operating in the preloading range are related as

Answer 47

**Δp = G^2**

Question 48

Pick out the **wrong statement**. In an **agitated vertical cylinderical reaction vessel**, the

Answer 48

**dished bottom vessel has very high power consumption.**