(1) Process Equipment and Plant Design Flashcards
(389 cards)
1
Q
Fresh water carrying pipelines in chemical industries are coloured with __________ color.
A
2
Q
Which of the following material is seldom used for pressure vessel construction?
A
3
Q
The ratio of shear stress to shear strain is called
A
4
Q
25 per cent cut segmental baffle means that the baffle
A
5
Q
Liquid/petroleum fuel storage tanks are built underground (as in case of petrol pumps), when the storage capacity is less than __________ kilolitres.
A
6
Q
Le/D for fully open globe value may be around
A
7
Q
Lug support is
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8
Q
Pick out the wrong statement pertaining to the use of valve tray, seive tray and bubble cap trays in continuous distillation column.
A
9
Q
With increase in the number of shell passes, the value of FT
A
10
Q
Holes of a sieve tray are arranged in triangular pitch of __________ times the hole diameter.
A
11
Q
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
12
Q
The stress developed in a material without any permanent set is called the
A
13
Q
In a shell and tube heat exchanger, the ‘tube pitch’ is defined as the
A
14
Q
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
15
Q
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)
A
16
Q
The value of fouling factor depends upon the
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17
Q
In case of bubble cap distillation column of diameter greater than 1.2 metres, the cap diameter is roughly about __________ cms.
A
18
Q
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.
A
19
Q
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
A
20
Q
In a heat exchanger, shell side fluid velocity can be changed by changing the tube
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21
Q
Where does the maximum tensile strength occur in a thick cylindrical vessel subjected to internal pressure?
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22
Q
It is not desirable to design a heat exchanger for LMTD correction factor, FT, of less than
A
23
Q
A rivetted joint does not fail by __________ of rivets.
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24
Q
Triangular pitch tube layout as compared to square pitch in a shell and tube heat exchanger
A
25
Bracket supports are the most suitable for supporting __________ vessels.
26
In a multipass shell and tube heat exchanger, the shell side cross flow area does not depend upon
27
Two iron pipes of the same nominal diameter but different schedule numbers will have the same
28
Steam side heat transfer co-efficient for design consideration under ordinary condition can be assumed to be about __________ kcal/hr.m2.°C.
29
Pick out the wrong statement.
30
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.
31
In chemical process equipments, the conical bottom heads used, usually has an apex angle of
32
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.
33
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
34
Correct use of 'factor of safety' is very important in equipment design. It is defined as the ratio of the
35
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.
36
__________ tray arrangement is recommended for distillation column having diameter upto 4 ft.
37
What is the value of 'q' for saturated liquid feed to a distillation column?
38
In perforated plate towers, the
39
The main purpose of providing stepping on the trays is to
40
The operating pressure drop range in a bag filter is about __________ mm water gauge.
41
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.
42
For laminar flow (NRe < 2100) in steel pipe, the optimum inside pipe diameter is given by
43
Pick out the correct statement.
44
Wall thickness of schedule 40 pipe as compared to that of schedule 80 pipe is
45
Pick out the wrong statement pertaining to the design of a basket type evaporator.
46
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.
47
Speed of the drum of the rotary vacuum filter normally ranges from __________ rpm.
48
A stuffing box is used for
49
Pressure drop (Δp) and the superficial gas mass velocity (G) in case of packed absorption tower operating in the preloading range are related as
50
Pick out the wrong statement.
In an agitated vertical cylinderical reaction vessel, the
51
Needle valves are generally not used for
52
Height equivalent to a theoretical plate (HETP) is the height of packing that will give the same separation as one theoretical plate in gas-liquid mass transfer operations like distillation, absorption/stripping and humidification/dehumidification. HETP which is experimentally determined, depends upon the
53
Pick out the wrong statement.
54
With increase in gas flow rate to fabric surface area ratio (Nm3/hr/m2 fabric surface area), the size & the cost of a bag filter
55
A head comprises of straight flange section, corner torus, section and central dished section. Crown radius and knuckle radius in a head is related respectively to the
56
Number of evaporators which can be used in service in a multiple effect evaporation system is limited by the
57
Which of the following is used to set the diameter of the distillation column?
58
Ponchon Savarit method is based on the use of enthalpy concentration diagram, which contains the bubble point curve (saturated liquid curve), dew point curve (saturated vapour curve) and equilibrium tie lines. As compared to McCabe-Thiele's method, this method
59
The optimum size ratio for two mixed reactors in series depends on the kinetics of the reaction and the conversion level. For reaction orders more than one, the
60
In a shell and tube heat exchanger, tube side __________ of the mass velocity.
61
Which of the following is not a graphical method (but is an analytical method) for the calculation of theoretical number of stages in case of continuous binary distillation?
62
Saddle supports are used for supporting __________ vessels.
63
The diameter of a propeller agitator used in agitation tank ranges from __________ percent of the tank diameter and its peripherial speed is normally 300 to 500 metres/minute.
64
In packed towers provided with saddle packing, liquid redistributors are positioned at every __________ times column diameter or 6 metres whichever is less.
65
Optimum reflux ratio in a continuous distillation column is determined by the
66
Cooling water fouling factors vary in the range of 0.001 to 0.003
67
Minimum recommended baffle spacing in a shell and tube heat exchanger is about (where, D = shell diameter)
68
The maximum liquid gradient over a tray must not exceed
69
An underdesigned steam trap will
70
The slope of the feed line in distillation opeartion is given by (where, q = fraction of the feed stream that is liquid.)
71
Speed of industrial paddle agitator ranges from __________ rpm.
72
_________ strain is measured using a 'strain rosetter'.
73
Thin spherical shells subjected to internal pressure, develop __________ stresses.
74
With increase in the reflux ratio for a fixed production from a continuous binary distillation column, the __________ decreases.
75
The slope of operating line in the rectifying section of a distillation column is unity, if the reflux ratio is
76
Vertical vessels are not supported by
77
With increase in pressure drop (for a given particle size), the dust collection efficiency of a cyclone separator will
78
Spherical shaped pressure vessel is considered to be the most ideal, because it can
79
An adequate clearance between the tray and the shell wall of a distillation column is provided to
80
Overall tray efficiency of a distillation column is the ratio of the number of
81
Pick out the wrong statement about the design of a sieve plate column.
82
Generally, no corrosion allowance in wall thickness of a part is required, if the thickness is more than __________ mm.
83
Multiple blade paddle agitator is used for mixing high viscosity liquids/paste in which the paddle diameter is commonly 0.8 times the tank diameter. However, the width of the blade is in the range of __________ times the paddle diameter.
84
In a __________ rivetted joint, the rivets in the various rows are opposite to each other.
85
Pick out the wrong statement:
86
Generally, elliptical dished heads
87
Pick out the wrong statement pertaining to the comparative evaluation of performance of the packed tower and the plate tower.
88
The circumferential (hoop) stress in a thin walled cylinderical vessel under internal pressure is
89
Le/D for fully open gate valves would be
90
LMTD correction factor is used in heat exchanger design for
91
Floating head heat exchangers are used for the
92
The most common standard size of bubble caps used in industrial operation is
93
Compensation against openings in process vessels for giving inlet and outlet connections, for providing sight glasses and manholes etc. is provided for strength and rigidity. The most efficient type of compensation is of __________ type.
94
In case of a continuous distillation column, increase in reflux ratio may result in the
95
In a distillation column, the minimum residence time for liquid in the downspout is about __________ seconds.
96
Thickness of the frame of a plate and frame filter as compared to that of plates is
97
Which of the following factors affect the pressure drop in a co-current gas-liquid absorption packed tower?
98
The thickness of heat transfer plates used in the plate type heat exchanger ranges from __________ mm, pressed in a single piece provided with grooves & corrugations.
99
Rivets are generally specified by the
100
Length to diameter ratio of most rotary driers is in the range of
101
Tube wall thickness depends on the cor-rosiveness of the fluids and their operating pressure & temperature and is specified by Birmingham wire gauge (B.W.G)-a number which varies from 8 to 18 with the numbers 14 and 16 being more commonly used. Outside diameter of tubes varies from about 15 to 50 mm; however a tube of less than __________ mm outside diameter is generally not recommended for fouling fluids.
102
Angled baffles are preferred in the agitation tank to control the swirling action; if the viscosity of the liquid to be mixed is about 200 poise. However, the baffle may be completely eliminated for mixing liquids having viscoisty above __________ poise.
103
Ratio of tube length to shell diameter for a shell and tube heat exchanger is
104
The dust collection efficiency of a cyclone separator
105
In a shell and tube heat exchanger, the overall heat transfer co-efficient is proportional to the tube side (volumetric flow rate)0.8. This is valid, only when the ratio of the tube side film resistance to the total resistance is almost equal to
106
Which of the following types of reactors is the safest from operation point of view?
107
In a bag filter, the pressure drop increases directly as the
108
The LMTD correction factor (FT) is applied in __________ heat exchangers.
109
Movement of pipeline caused by thermal expansion is taken care by providing
110
For a cylindrical shell, (subject to the thickness of uppermost course being more than the minimum for diaofthe tank in question), the thickness of the courses of shell
111
In the design of a paddle agitator, the ratio paddle dia/tank dia is normally taken as
112
The design stress, which is more than the damaging stress, is the least unit stress that will render a member unfit for service before the end of its normal life. The design stress factor or factor of safety indicates the margin between design stress and the __________ stress.
113
Hole diameter of the seive trays in the distillation column ranges from __________ mm.
114
Factor of safety (i.e., overdesign factor) in heat transfer equipments is about __________ percent more than the actual/theoretical design factor.
115
For annular flow of a fluid, the ratio of the equivalent diameter for pressure drop calculation to the equivalent diameter for heat transfer calculation is
116
In actual operation of distillation column, the vapour is not distributed uniformly among the bubble caps, primarily because of the
117
The minimum shell thickness for tank ≤ 15 metres diameter is limited to __________ mm, for reasons of elastic stability.
118
If 'D' is the inside diameter of the shell of a shell and tube heat exchanger, then the baffle spacing is usually in the range of
119
Brass valves are usually made for pipe sizes __________ inches.
120
At the following point for a given packing and set of fluids, the pressure drop per metre of packed height, with variation in fluid rates and operating pressure
121
In a shell and tube heat exchanger, triangular pitch arrangement as compared to square pitch arrangement
122
Pick out the wrong statement about routing of fluids in a shell and tube heat exchanger.
123
The necessary wall thickness for a metallic storage vessel is a function of the
124
In a multiple effect evaporator system having 'n' effects, the amount of water evaporated per unit surface area in approximately equal to __________ times that in a single effect.
125
Pick out the wrong statement.
126
Pick out the wrong statement pertaining to the design of a horizontal tube evaporator.
127
Weep holes provided in the plates of a distillation column
128
Steam is preferred to be used as a heating medium in heat exchangers, because of its
129
__________ shapedroof is the most commonly used roof for cylinderical storage tanks.
130
Pick out the wrong statement pertaining to 'Horton sphere' used for the storage of liquid ammonia.
131
Value of Peclet number = ∞, is the representative of
132
Le/D for a Tee (used as elbow, entering branch) would be
133
In most of the shell and tube heat exchangers, the tube pitch is generally __________ the tube diameter.
134
In a distillation column, bubble caps are located on trays with a pitch of __________ times the outside diameter of the caps.
135
1.2 to 3.8 cms is the value of the
136
Accidents in chemical plants are mostly due to
137
For identical operating conditions, the pressure drop over __________ tray is the highest out of the following.
138
A perforated plate has holes of diameter dn arranged in a pitch ph. Each hole has a tube of I.D. dt passing through it. The ligament efficiency is given by
139
__________ is the determining factor for the number of bubble caps to be used per tray.
140
Pick out the wrong statement about distillation operation
141
Low pressure steam (with saturation temperature between 105 to 120°C) is usually used in the vacuum evaporators, which normally employ a vacuum of about __________ mm Hg (referred to a 760 mm mercury barometer).
142
Which of the following is the best tube material from thermal conductivity point of view alone?
143
Normal screwed fittings are used for pipes upto a diameter of __________ inches.
144
In a shell and tube heat exchanger, the clearance of the tube is generally
145
Diameter of the seive tray column is determined by the
146
For a given fluid, as the pipe diameter increases, the pumping cost
147
Maximum acceptable total liquid gradient over a tray is about __________ mm.
148
In case of a 'thin' pressure vessel, the ratio of its diameter to wall thickness is
149
High pressure fluid in a shell and tube heat exchanger should preferably be routed through the
150
Bubble cap tray is the most commonly used tray in large distillation column, because
151
In common bubble cap distillation column design practice, riser area is approximately equal to (where, Aa = Annular passage area, and Sa = Slot area)
152
Heat transfer co-efficient, hG(Kcal/hr.m2 .°C) and mass velocity of air, G (kg/hr.m2 ) for air flow parallel to the surface in case of constant drying rate in batch drying is related as hG = 0.0176G0.8. But when the flow of air perpendicular to the surface is encountered, this equation changes to
153
In the agitators, the power required will be changed with the increase of diameter of agitator (D) as
154
Apex angle of conical heads used in the bottom heads of chemical process equipments is usually
155
Pressure drop due to pipe fittings can be estimated by the equation, https://www.indiabix.com/_files/images/chemical-engineering/process-equipment-and-plant-design/561-40-1.png
, where, Le = equivalent length of straight pipeline which will incur the same frictional loss as the fitting and D = diameter of the fitting. The value of Le/D (dimensionless) for 45° elbow and 180° close return bends would be respectively around
156
A pressure vessel is said to be made of 'thick' shell, if the ratio of its diameter to wall thickness is
157
Rate of filtrate delivery is inversely proportional to the
158
Tube side heat transfer co-efficient for turbulent flow of liquid through tubes is proportional to
159
Circumferential (hoop) stress in a thin cylindrical vessel under internal pressure is __________ the longitudinal stress.
160
The dust collection efficiency of electrostatic precipitator increases with increase in the
161
For storing hazardous chemicals in large storage tanks, the minimum safe distance between the two tanks should range between __________ times the tank diameter.
162
Which of the following factors determine the amount of entrainment in a distillation column?
163
The absorption factor is defined as (where, S1 = slope of the equilibrium curve, S2 = slope of the operating line)
164
In shell and tube heat exchangers, straight tie rods are used to
165
In a rotary drier, the average retention time of solid is(where Z = length of the drier, metres ρ = apparent solid density, kg/m3 L = flow rate of dry solids, kg/see. m2 drier cross-section H = hold up of solid.)
166
In case of design of a shell and tube heat exchanger,
167
In a cylinderical vessel subjected to internal pressure, the longitudinal stress σL and the circumferential stress, σn are related by
168
Nominal size of a pipe is an indication of its __________ diameter.
169
Excessive liquid gradient on a tray may result in the
170
The ratio of tube length to shell diameter in case of liquid shell and tube heat exchanger ranges from
171
In a double pipe concentric heat exchanger, the equivalent diameter of annulus for heat transfer would be (where, D1 and D2 are I.D. of inner and outer pipes)
172
What is the slope of the operating line in the stripping section of a distillation column?
173
__________ shaped roof is most commonly used for cylindrical tanks.
174
In a thin cylindrical shell, the hoop stress is __________ stress.
175
Commercial packed scrubbers are normally designed for a pressure drop range of __________ mm water coloumn per metre of packed height.
176
The retention time of material in a rotary dryer depends upon its
177
In actual operation of a bubble cap distillation tower, the __________ at the bottom of the tower is more than that at the top of the tower.
178
Rotary driers are most economically designed for the number of heat transfer units (HTU) from
179
The difficulty of liquid distribution in packed towers is accentuated, when the ratio of tower diameter to packing diameter is
180
A forced circulation long tube vertical evaporator as compared to the natural circulation evaporator
181
An increase in the liquid resistance to interphase mass transfer and a resultant reduction in plate efficiency is caused by
182
In the design of a bag filter, the gas temperature is an important consideration, as it affects the
183
With increase in temperature drop (in a shell and tube heat exchanger), the LMTD correction factor, FT
184
The normal range of velocity of steam in pipes is __________ m/sec.
185
__________ dished head is the strongest of all.
186
Pick out the correct statement.
187
"A claming section" before the liquid flows into the downcomer is privided to
188
The units of Young's modulus of elasticity and __________ are the same.
189
In the design of a shell and tube heat exchanger, the corrosion allowance
190
Vertical condenser is advantageous to the horizontal condenser from operation point of view, when
191
Hazards associated with the relief valve leakage for extremely hazardous material storage can be taken care of by providing
192
Minimum baffle spacing recommended in a shell and tube heat exchanger is equal to
193
__________ liquor is best handled in a long tube vertical evaporator.
194
Theoretically calculated diameter of the stripping section of the continuous rectification column is __________ that of the enriching section.
195
Hold up of material in a operating rotary drier is in the range of
196
A binary liquid azeotropic mixture has boiling point higher than either of the components, when it shows __________ deviation from Raoult's Law.
197
The testing pressure of storage tanks and pressure vessels designed as per Indian standard codes should be about __________ times.the design pressure.
198
Flanges are connected to pipes by
199
The ratio of down take area to cross-sectional area of the tube, for calendria type evaporator ranges from
200
Shortest distance between two tubes is
201
__________ tower is the most suitable gas-liquid contacting device involving highly corrosive fluids.
202
At equal mass velocities, the values of film co-efficients for gases as compared to that for liquids are generally.
203
The ratio of the largest load in a test to the original cross-sectional area of the test specimen is called the __________ stress.
204
Baffle spacing is generally __________ the I.D. of the shell.
205
The wall thickness of thin cylindrical shell with hemispherical ends is __________ that of the spherical ends.
206
A 'rupture disc' is provided in chemical equipments as an accessory meant for
207
In a vertical short tube evaporator (Calendria type), the
208
In a multipass shell and tube heat exchanger, the problem of differential expansion between the shell and tube passes is taken care of by using a
209
In a shell and tube heat exchanger, the shortest centre to centre distance between the adjacent tubes is
210
Any shell opening greater than 5 cms for a storage tank must be reinforced for reason of
211
Minimum tube pitch recommended for shell and tube heat exchangers is about __________ times the outside diameter of the tube.
212
Liquid redistribution should be done in a packed tower packed with raschig rings every 6 metres or __________ times the column diameter, whichever is lower.
213
Slope of countercurrent flow rotary drier is in the range of __________ meter/metre.
214
In case of saddle packing (e.g., berl and intralox saddles), the maximum size of the packing should not exceed __________ of the column diameter.
215
Seamless pipe is made
216
The thermal stress in a metallic bar does not depend upon the
217
The minimum baffle height should be
218
For turbulent flow (NRe > 2100) of low viscosity fluid (μ > 20cp) in steel pipes, the optimum inside pipe diameter is given by(where, Q = fluid flow rate, ft3/sec.ρ = fluid density, lb/ft3 μ = fluid viscosity, centipoise Di = optimum inside pipe diameter, inches)
219
To avoid the tearing off the plate of an edge, the margin (i.e., the minimum distance from the centre of the rivet hole to the nearest edge of the plate) should be equal to
220
The normal range of velocity of water in pipes is __________ m/sec.
221
Baffles are provided in a shell and tube heat exchanger to increase the turbulence and velocity of the shell side fluid. Which of the following shaped baffles does not fall in the category of transverse baffle?
222
A certain pressure vessel manufacturer avoids doing reinforcements calculations for openings by always providing a reinforcing pad extending upto double the diameter of the opening and of the same material and thickness as that of the shell wall. If area compensation is accepted as a code guideline, his approach leads to safe design
223
In a __________ rivetted joint, the number of rivets decreases from the innermost row to the outermost row.
224
Large process vessels operating under extreme temperature and pressure conditions are normally clad/ lined with materials like stainless steel, aluminium, nickel & its alloys, copper & its alloys and titanium. The cladding thickness is generally about __________ percent of the total thickness.
225
Heat transfer co-efficient for a horizontal condenser as compared to a vertical condenser operating under similar conditions is
226
Pick out the wrong statement pertaining to the design of the distillation column.
227
The longitudinal stress induced in a thin walled cylinderical vessel under internal pressure is
228
In distillation columns, bubble caps are held in place over trays by
229
The buckling tendency of compression members is always in the direction of the
230
In case of plain carbon steel, butt welded joints are used for shell plate thickness ≤ __________ cms.
231
The average velocity in the tubes of a 1-4 heat exchanger is __________ times that in 1-1 heat exchanger having the same size & number of tubes and operated at same liquid flow rate.
232
Hoop (circumferential) stress induced in a thin walled 'Horton Sphere' used for the storage of liquid ammonia under pressure is
233
When one of the fluids is highly corrosive and has fouling tendency, it should
234
The raio, propeller agitator dia/tank dia is normally taken as
235
A/an __________ is used for changing the direction of a pipeline.
236
Maximum plate efficiency is achieved in case of __________ flow.
237
The LMTD correction factor (FT) is defined as the
238
The clearance between two tubes in a shell and tube heat exchanger is known as 'ligament', whose minimum value is __________ the outside diameter of the tube, but in no case it should be less than 4.5 mm.
239
The ratio for the rate of washing to the final rate of filtration in a washing type of plate and frame filter is
240
Normally, the length to diameter ratio of rotary dryers varies form 4 to 10 and for its economic operation, the number of transfer units (NTU) for such dryers varies from
241
Value of Peclet number = 0, is the representative of
242
Poisson's ratio of a material is the ratio of unit lateral strain to the unit axial elongation within its elastic limit. The value of Poisson's ratio for structural and pressure vessel steel may be taken as
243
Removable connection of tubes to tube sheet is called
244
Stress-strain diagram for low carbon steel/mild steel is shown below in the Fig.
https://www.indiabix.com/_files/images/chemical-engineering/process-equipment-and-plant-design/572-178-1.png The point 'A' on the Fig. represents the
245
Typical static submergence for bubble cap plate column operating at atmospheric pressure may be around
246
In the allocated cap area, bubble caps are generally arranged on equilateral triangular pitch. Number of caps fixed on a plate is with a
247
The length of straight rectangular weir used on cross-flow trays is generally __________ the column diameter.
248
Le/D for couplings and unions would be
249
What is the slope of the operating line in the rectifying section of a distillation coloumn?
250
Stage efficiency for packed tower varies with the
251
The minimum plate spacing in most of the pertroleum refinery distillation columns (of dia > 3 ft) is normally __________ inches.
252
Joint efficiency (J) for a seamless pipe is
253
For a given design of bubble cap, the number of bubble caps to be used per tray is set by the
254
The shell side pressure drop in a shell and tube heat exchanger is maximum for __________ baffle.
255
The function of manholes provided in the shell of a distillation column is to
256
Back-trapping in a distillation column results due to
257
For a cylinderical vessel of moderate height, the weld joint efficiency for joints parallel to the cylinderical axis is given as 1.0, while for joints along the girth (circumference) it is given as 0.8. In calculating the shell wall thickness using code formula for an internally pressurised cylinderical vessel, what value of weld joint efficiency should be used?
258
Diameter of bubble caps used in high pressure columns is __________ as compared to that used in identical vacuum columns.
259
The ideal size of round bubble caps to be used in industrial distillation column having a diameter of 3-6 metres is __________ cms.
260
Lap joints are preferred for plates having thickness __________ mm.
261
In a distillation column, minimum clearance to be maintained betweeen the overflow weir and the last row of the bubble caps is __________ cms.
262
Which of the following lengths of heat exchanger tubes are normally not used in practice ?
263
A pipe is generally made of circular cross-section, because a circular cross-section has the
264
In case of a shell and tube heat exchanger, the effect of L/D on inside film heat transfer co-efficient (hi) vanishes after a Reynold number of
265
Equivalent diameter for heat transfer calculation for a duct of square cross-section having each side as 'd' will be
266
A cylindrical storage tank can have a self supported conical roof,
267
For high pressure process equipments/vessels, the connected nozzle should be
268
Smoker's equation for the calculation of number of equilibrium stages in a continuous binary distillation column is used, when the
269
Column support for the roof of cylindrical storage tank must be provided for
270
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?
271
In inclined long tube vertical evaporators, the tubes are inclined at an angle of
272
In a continuous distillation column, the optimum reflux ratio ranges from __________ times the minimum reflux ratio.
273
The wall thickness for a large high pressure pipeline is determined by the consideration of the
274
In the case of a shell and tube heat exchanger, the logarithmic mean temperature difference
275
Skirt support is the most suitable for supporting __________ vessels.
276
Baffles may be eliminated for
277
Generally, as the length of the liquid path on a tray is increased beyond 5 ft, the overall column efficiency
278
In packed absorption tower, onset of flooding usually occurs at a pressure drop of about __________ mm of water column per metre height of packing.
279
For pipe flows, head is proportional to __________ at constant capacity (where D = pipe diameter).
280
Friction factor for turbulent flow in a new pipe is given by
281
The minimum tray spacing in distillation column of diameter less than 3 ft is normally __________ inches.
282
Oxygen carrying pipelines in chemical industries are coloured with __________ colour.
283
Normally, the ratio of the total riser area to the tower cross sectional area (for bubble cap towers of diameter more than 3 ft) is around
284
Pick out the wrong statement about the design of seive plate column and the bubble cap column.
285
Maximum size of the raschig rings used in a packed tower is about __________ of the coloumn diameter.
286
Longitundinal stress induced in a thin walled cylindrical storage vessel is
287
The type of stress developed in a metallic bar on subjecting it to a change in temperature without allowing it to be deformed is __________ stress.
288
The safe distance of habitation from a hazardous chemical plant (TLV of its product < 1000 ppm) should be about __________ kms.
289
Pick out the wrong statement pertaining to a shell and tube heat exchanger.
290
Corrosion allowance in the design of pressure vessel/chemical equipment is not necessary, if
291
Maximum allowable vapour velocity in a bubble cap tower is determined by the
292
Normally, the plate thickness of the bottoms and roofs of vertically cylindrical storage vessels as compared to that of the cylindrical shell is
293
The practical representative values of HETP for a number of commercial operations lies within a range of __________ metre.
294
Of the pressure vessels, with same thickness but different diameters, which one withstands higher pressure?
295
Reflux ratio variation in a distillation column is between
296
Width and depth of grooves in the tube sheet holes normally are __________ inch respectively.
297
In condenser, the cooling water is passed in the tube side in a pass arrangement, because
298
In packed towers provided with pall rings liquid redistributors are positioned at heights of every 6 metres or 5-10 times the column diameter, whichever is less. Maximum size of the pall rings should not exceed __________ of the column diameter.
299
Height of the flights in the rotary drier is in the range of
300
Vapor velocity in a distillation column for non-foaming mixture is in the range of __________ times the flooding velocity.
301
Cylindrical storage tanks used for the storage of volatile liquids (e.g., naphtha) have __________ roofs.
302
Larger depth of liquid on the trays of a distillation column
303
Pick out the wrong statement.
304
Pick out the wrong statement.
305
In the downcomer of a distillation column, the minimum recommended residence time is about __________ seconds.
306
For identical situation, condensing film coefficient in case of a horizontal condenser is almost __________ the value expected in case of vertical condenser.
307
Diameter of rivet hole (d, mm) and the plate thickness (t, mm) are related by Unwin's formula as
308
A binary liquid azeotropic mixture has boiling point lower than either of the components, when it shows __________ deviation from Raoult's Law.
309
In which of the following evaporators, steam is fed inside the tube while the liquor is outside the tube?
310
A single pass air heater is connected to a two pass unit. For the air flow rate and other conditions remaining the same, the film heat transfer co-efficient for air will vary in the ratio of
311
In a multipass shell and tube heat exchanger, the baffles on shell side is primarily provided for
312
For turbine agitator, the impeller diameter is about
313
In a shell and tube heat exchanger having triangular pitch, the shell side equivalent diameter is given by
314
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.
315
Pick out the wrong statement.
316
Pick out the wrong statement pertaining to the design of a long tube vertical evaporator.
317
Which of the following is the most common type of baffle used in industrial shell and tube heat exchanger?
318
What is the minimum recommended ligament for square pitch arrangement in case of heat exchangers?
319
Pick out the correct statement
320
Safety valves are provided in chemical equipments to guard against excessive
321
The equivalent diameter for pressure drop is __________ that for heat transfer.
322
Most of the storage vessels/tanks are made cylindrical, because of the fact that a cylinder
323
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
324
Liquid gradient over the tray results due to the
325
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?
326
A high vapour velocity is required for high plate efficiency in a seive plate coloumn. The satisfactory value of operating vapor velocity for design purpose in seive plate column is about __________ percent of the flooding velocity.
327
The approximate liquid depth in an agitation tank is equal to (where, d = tank diameter)
328
Baffle width is normally taken as __________ times the tank diameter.
329
A cylinderical pressure vessel of volume 6 πm3 has to be designed to withstand a maximum internal pressure of 10 atm. 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
330
Which of the following packing materials provides for maximum mass transfer?
331
__________ of water makes it a widely used coolant in heat exchangers.
332
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)
333
Fouling factor must be included in the calculation of over all design heat transfer coefficient, when the liquid
334
Lug support is meant for supporting __________ vessels.
335
Overall mass transfer co-efficient in case of absorption of __________ in water is based on the gas film co-efficient only, as the mass transfer process is gas film (phase) controlling.
336
Which tube arrangement in a heat exchanger would facilitate highest heat transfer rate?
337
In case of 1.5" heat exchanger tubes, the inside flow area __________ with decrease in BWG.
338
Cylindrical pressure vessels in horizontal condition is generally supported on a __________ support.
339
Pressure drop per tray in the atmospheric distillation column is about __________ psi.
340
Welded joint efficiency in the design of chemical process equipment is taken as
341
The thickness of segmental baffles (25 -35% cut truncated plates usually) is generally __________ the tube wall thickness.
342
The safe height (h) to diameter (d) ratio (i.e., h/d) for liquid/petro fuel storage tank of capacity more than 45 kilolitres is less than
343
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.
344
The ratio of linear stress to linear strain is termed as the
345
__________ head is the most economical for cylindrical vessels designed for operating at high pressure (> 15 atm.).
346
Bubble cap plate column is
347
In seive plate column, holes are drilled or punched in sizes ranging from 2.5 to 12 mm (5 mm being widely used). The hole pitch is normally __________ times the hole diameter to give the required hole area.
348
Pick out the wrong statement.
349
The force due to wind load acting on a tall vessel depends upon its
350
Bubble cap diameter used for the distillation column having diameter ranging from 1.5 to 4.5 metres is about __________ mm.
351
Power required for agitation depends upon the
352
Tube height in a calendria type evaporator is normally less than __________ metres.
353
Pick out the wrong statement.
354
For a 25 mm hole drilled in plates to be rivetted, the shank diameter of the rivet should be __________ mm.
355
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)
356
Optimum economic pipe diameter for fluid flow is determined by the
357
Pressure differential maintained across a continuous rotary vacuum filter is in the range of __________ mm Hg column.
358
Vertical storage vessels are never supported by __________ support.
359
In a double pipe (concentric) heat exchanger, the hydraulic radius for heat transfer (for a fluid flowing through the annulus) would be
360
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)
361
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.
362
What is the slope of the feed line, if the feed to a distillation column is a saturated liquid?
363
Filtration rate is affected by the
364
Liquid gradient over a tray can be minimised by
365
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
366
Le/D for 90° elbow (medium radius) and 90°square elbow would be respectively around
367
__________ heat exchanger is also known as 'hair pin type' exchanger,
368
What is the value of 'q' for saturated vapor feed to a distillation column ?(where q = fraction of the feed stream that is liquid.)
369
In hydrostatic testing of welded pipe (for leakage, strength etc.) the ratio of minimum hydrostatic test pressure to internal design pressure is around
370
Frame thickness in the plate and frame filter press is normally in the range of __________ inches.
371
Cylinderical shell thickness of rotary drier is generally __________ mm.
372
The ratio of lateral strain to linear strain is termed as the
373
The distance between the centre of a rivet hole to the nearest edge of the plate is called
374
Mc Cable Thiele method used for finding theoretical stages in a distillation column assumes that the
375
A minimum clearance of about __________ mm is maintained between the distillation column wall and the bubble cap.
376
Pick out the wrong statement.
377
Pick out the wrong statement pertaining to shell and tube heat exchanger.
378
Wind load consideration in the design of a support can be neglected, when the vessel is
379
Souders Brown equation given by, https://www.indiabix.com/_files/images/chemical-engineering/process-equipment-and-plant-design/590-379-1.png , is used for the calculation of the __________ in a continuous distillation column.
380
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
381
Steam economy is defined as the amount of evaporation per unit amount of steam used, while the capacity is the total evaporation obtained per hour. Use of multiple effect in evaporation
382
Le/D for a Tee (used as elbow, entering run) would be around
383
Log mean temperature difference in case of multi-pass shell and tube heat exchanger is always
384
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.
385
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").
386
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
387
Scale up problem in design based on the similarity concept takes into account __________ similarity.
388
__________ closure is the weakest enclosure for cylindrical vessels.
389
Which of the following efficiencies can be greater than 100%?
