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GUJARAT TECHNOLOGICAL UNIVERSITY
BRANCH NAME: Chemical Engineering (05)
SUBJECT NAME: PROCESS EQUIPMENT DESIGN-II
SUBJECT CODE: 2170502
B.E. 7th SEMESTER
Type of course: Chemical Engineering
Prerequisite: The student should have basic understanding of Unit Operations of Chemical
Engineering and mechanical properties associated with the material.
Rationale:
Equipment design involves modifications and additions to existing plants or creating design
layouts of plant / equipments. With rapid rate of increase in the advancement of knowledge,
it is important that the students should know the relevant application for equipment design. It
has been observed conclusively that practice in using the reference literature and software has
helped the students to secure jobs and also to perform better in profession.
Teaching and Examination Scheme:
Teaching Scheme Credits Examination Marks Total Marks L T P C Theory Marks Practical Marks
ESE (E)
PA (M) ESE (V) PA (I) PA ALA ESE OEP
3 0 3 6 70 20 10 20 10 20 150
Content:
Sr.
No. Content
Total
Hrs
%
Weightage
1 Introduction :
Concept of internal & external design pressure, design stress &
design temperature, Different types of equipments, Static & rotary
equipments, Different types of static equipments, Various
mechanical properties of material, Different methods of fabrication,
Different types of welding joints, Joint efficiency, Radiography.
04 8
2 Mechanical design of Pressure vessel:
Introduction of ASME Code sec-VIII, DIV-I & IS-2825,
Classification of pressure vessel as per IS-2825,Mechanical design
of Shell: shell subjected to internal pressure, Graphical & analytical
method for Shell subjected to external pressure, design of shell for
external pressure with & without stiffening ring, Different types of
head, their selection criteria, Mechanical design of heads: Heads
subjected to internal pressure, Graphical & analytical method for
heads subjected to external pressure, Different types of Nozzles,
their selection criteria, Design of nozzle pipe, Design of
reinforcement pad by area for area method, Different types of
flanges, Different types of standard flanges, their important features
& selection criteria, Different types of flange facings & their
20 37
Suggested Specification table with Marks (Theory):
Distribution of Theory Marks
R Level U Level A Level N Level E Level C Level
7 21 21 7 14 -
Legends: R: Remembrance; U: Understanding; A: Application, N: Analyze and E: Evaluate
C: Create and above Levels (Revised Bloom’s Taxonomy)
Note: This specification table shall be treated as a general guideline for students and teachers. The
actual distribution of marks in the question paper may vary slightly from above table.
Reference Books:
1. Process Equipment Design - Vessel Design - L.E. Brownell & E.H.Young, First Edition.
2. Illustrated Process Equipment Design by S B Thakore, Second edition,.
3. Process Equipment Design - M.V.Joshi & V V Mahajani, Third edition.
4. Process Equipment Design (Mechanical Aspects) By B.C.Bhattacharya.
selection criteria, Different types of gaskets, their selection criteria,
Design of ring flange.
3
Mechanical design of Reaction Vessel:
Mechanical design of shell, head, Jacket, coil, agitator, nozzle, body
flange, etc., Different types of agitators & their selection criteria,
Different types of agitator shaft sealing system & their selection
criteria, Different types of power transmission system,
Determination of power required for agitation, shaft diameter, blade
thickness, etc., Different types of jackets & their selection criteria,
Selection between coil & jacket
06 11
4
Mechanical design of Storage Tank:
Classification of storage tank as per IS-803, Capacity of storage
tank, its diameter & height, Design of shell and bottom plate for
storage tank, Design of Self supported conical roof, Design of
structured supported conical roof as per API 620, Selection of
column, girders and rafters, Roof curb angel, Floating roof.
05 9
5 Mechanical design of Shell & Tube Heat Exchangers:
Mechanical design of Shell, tube, tube sheet, head, channel shell, ,
etc. of shell & tube heat exchanger 05 9
6 Mechanical design of Vertical tall tower (Distillation Column):
Mechanical design of shell, head, tray support, nozzle, body flange,
for Vertical tall tower, Determination of shell thicknesses at various
heights for tray tower & packed tower in case of internal & external
pressure, Different types of tray supports & their selection criteria,
design of horizontal structural member with periphery ring type
packing support
08 15
7 Supports :
Different types of supports, Mechanical design of bracket support,
skirt, support & saddle support
06 11
Course Outcome:
After learning the course the students should be able to:
1. Design process equipment and modify the design of existing equipment to new process
conditions or new required capacity.
2. Build a bridge between theoretical and practical concepts used for designing the equipment
in any process industry.
3. Create understanding of equipment design with mechanical concept.
4. Review the importance of design concepts in process industry.
List of Tutorials:
Prediction of Physical properties
Estimation of various design parameters for various equipments.
Solution of various problem used in the designing of equipments.
List of Open Source Software/learning website:
Students can refer to video lectures available on the websites including NPTEL lecture
series.
Students can refer to the CDs available with some reference books for the solution of
problems using software/spreadsheets. Students can develop their own
programs/spreadsheets for the solution of problems.
MIT Open course lecture on Equipment design.
Literature available for Process design of equipment in plant / industry.
ACTIVE LEARNING ASSIGNMENTS:
The tutorials will be given to students which will cover entire content of the subject. The students
will be required to solve all problems given in the tutorials. Some of the problems they have to
solve using programming language or software. The list is given below:
Excel Spreadsheets
Polymath
Matlab/Scilab, etc.
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII (NEW) - EXAMINATION – SUMMER 2017
Subject Code: 2170502 Date: 02/05/2017 Subject Name: Process Equipment Design -II Time: 02.30 PM to 05.30 PM Total Marks: 70 Instructions:
1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks.
Q.1 (a) Explain the function of the following parts for the shell and tube heat
exchanger. (i) Baffles (ii) Tie rods (iii) Spacers (iv) Expansion joint (v) Tube
side pass partition (vi) Tube sheet (vii) Support.
07
(b) Define (i) Elasticity (ii) Toughness (iii) Fatigue (iv) Creep (v) Poisson’s ratio
(vi) Moment of inertia (vii) Welding joint efficiency factor.
07
Q.2 (a) Explain the various types of flanges used in industry. 07
(b) Turbine agitators operating in a vessel of 1600 mm diameters is to be designed
with the following data :
Internal design pressure = 5 kgf/cm2
Agitator diameter = 500 mm
Max. agitator RPM = 200
Liquid in vessel m = 600 cP
Specific gravity = 1.2
Over hang length of shaft = 1200 mm
No. of agitator blade = 6
Elastic limit = 250 N/mm2
Permissible shear stress in shaft = 55 N/mm2
Modulus of Elasticity ‘E = 19.5 x 104
Power number = 6 for NRe < 4500
= 4.5 for NRe > 4500
a) Calculate powers required & suggest suitable motor HP
b) Calculate shaft diameter.
07
OR
(b) Write a short note on safety valves. 07
Q.3 (a) Explain design procedure for saddle support.
07
(b) Discuss about different types of agitators and their selection criteria.
07
OR
2
Q.3 (a) A process vessel is to be designed for the maximum operating pressure of 500
kN/m2. The vessel has the nominal diameter of 1.2 m and tangent to tangent
length of 2.4 m. The vessel is made of IS : 2002 – 1962 Grade 2 B quality steel
having allowable design stress value of 118 MN/ m2 at working temperature.
The corrosion allowance is suggested to be 2 mm for the life span expected for
the vessel. The vessel is to be fabricated according to class 2 of Indian standard
specifications which stipulate the weld joint efficiency of 0.85.
a) What will be the standard plate thickness to fabricate this vessel?
b) If a spherical vessel having the same diameter and thickness is fabricated
the same quality steel, what maximum internal pressure the sphere will
withstand safely?
07
(b) Discuss the design of tray support.
07
Q.4 (a) Examine the data given below to evaluate the requirement of compensation for
the nozzle opening in a cylindrical shell. Find out ring pad dimensions.
1) Outside diameter of the shell – 2 m
2) Maximum working pressure – 3.5 Mn/ m2
3) Wall thickness for the shell – 0.05 m
4) Corrosion Allowance – 3 x 10-3 m
5) Weld joint efficiency factor ( Class I ) – 1
6) Allowable stress (IS: 2002 – 1962 – 2A) – 96 Mn/ m2
7) Outside diameter of nozzle (seamless )- 0.25 m
8) Nozzle – wall thickness - 0.016 m
9) Length of nozzle above surface – 0.1 m
07
(b) Explain in brief about classification on unfired vessel as per IS – 2825. 07
OR
Q.4 (a) Explain in detail basic properties of material. 07
(b) Why are gaskets used? Write in brief on various types of gaskets. 07
Q.5 (a) Discuss in detail the various types of jackets used for heating and Cooling.
07
(b) Discuss the design steps for column supported conical roof.
07
OR
Q.5 (a) Discuss about the various types of fabrication technique used for fabrication of
pressure vessel.
07
(b) A fractionating tower is 4 m in outside diameter by 6 m in length from tangent
line to closures. The tower contains removable trays on a 1m tray spacing and is
to operate under vacuum at 400 0C. The material of construction is IS: 2002 –
1962 Gr. I plain carbon steel. Determine the required thickness of the shell
without stiffeners and then with stiffeners located at the tray positions.
07
*************
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII(NEW) • EXAMINATION – WINTER 2016
Subject Code:2170502 Date:21/11/2016
Subect Name:Process Equipment Design –II
Time: 10.30 AM to 1.30 PM Total Marks: 70
Instructions:
1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks.
Q-1 (a) Design the bracket support for the reaction vessel with the following data.
O D of shell - 1052.7 mm, Thickness of shell - 6.35 mm, Height of vessel -
2.1524 m, Clearance from vessel bottom to foundation - 0.75 m, Weight of vessel
with contents - 3918.9 kg, Wind pressure - 100 kgf/m2, Bolt circle diameter -
1202.7 mm, Size of base plate for bracket - 150 mm × 150 mm, Size of C channel
- 150 mm × 75 mm, Height of bracket from foundation - 2.0264 m, C/S area of C
channel - 20.88 cm2, Modulus of section - 19.4 cm3, Radius of gyration - 2.21 cm,
Maximum allowable tensile stress - 1400 kgf/cm2, Maximum allowable
compressive stress - 1233 kgf/cm2, Maximum allowable bending stress - 1575
kgf/cm2. Assume the height of triangular portion of bracket - 145 mm.
10
(b) Explain “Radiography test” for pressure vessel. 04
Q-2 (a) Define the two most important stresses generated in a thin cylindrical shell and
discuss the classification of the unfired pressure vessel as per IS – 2825. 07
(b) State and discuss the various types of flanges used in industries. 07
OR
(b) What is gasket? Define gasket seating stress and discuss the various types of
gaskets used in industries. 07
Q-3 (a) A Reactor of 800 mm inside diameter is covered with hemispherical head at the
bottom. Inside working pressure is 75 kgf/cm2 (g) & working temperature is 70 oC.
Reactor is covered with plain jacket such that 75% length of shell & bottom
hemispherical head is covered with jacket. Cooling water is circulated inside the
jacket by pumping with a centrifugal pump having a shut off discharge pressure
7.0 kgf/cm2(g). The hemispherical head is fabricated from SA-516 Grade 70. The
maximum allowable stress at design temperature is 610 kgf/cm2. Modulus of
Elasticity of plate material (E) = 193 × 103 N/mm2. Poisson’s ratio (µ) = 0.3, ρ =
7.83 gm/cm3, Joint efficiency (J) = 0.85. Take 3 mm corrosion allowance. Find: (i)
thickness of the head (ii) volume of head and (iii) weight of the fabricated head
06
(b) (i) Briefly discuss about Fatigue and Creep.
(ii) Discuss stress vs strain curve. 08
OR
Q-3 (a) Turbine agitators operating in a vessel of 1.6 m diameter is to be designed with the
following data.
Internal design pressure – 5 kgf/cm2, Agitator diameter – 500 mm, Maximum
agitator rpm – 200, Viscosity of liquid – 600 cp, Specific gravity of liquid – 1.2,
Over hang length of shaft – 1.2 m, No. of agitator blade – 6, Elastic limit – 250
N/mm2, Permissible shear stress in shaft – 55 N/mm2, Modulus of elasticity – 19.5
× 105 kgf/cm2. Calculate (i) power required and (ii) shaft diameter and (iii) critical
speed. Power number – 8 for NRe < 1500, 6 for 1500 < NRe < 3000, 4.5 for 3000
< NRe < 4500, 3 for 4500 < NRe < 6000 and 2 for NRe > 6000.
10
(b) Briefly explain the uses of various types of jackets for reaction vessel. 04
2
Q-4 (a) Determine the total number of shell plates and plate thickness of a storage tank to
store Phosphoric acid of 85% w/w for phosphoric acid plant having production
capacity of 762.83 MT. Density of pure H3PO4 is 1834 kg/m3. Allowable stress of
Monel is 170 MPa and D/H is 1.5. Corrosion allowance is negligible.
07
(b) Explain Normal and Emergency venting for storage vessel. 07
OR
Q-4 (a) Examine the data given below to evaluate the requirement of reinforcement pad
for the nozzle opening in cylindrical shell. OD of shell = 2 m, maximum working
pressure within shell = 3.5 MN/m2, thickness of shell =0.05 m, corrosion
allowance = 3 mm, joint efficiency of nozzle and shell = 1, MOC = IS 2002,
Allowable stress = 96 MN/m2, Density = 7800 kg/m3, OD of nozzle = 0.25 m,
Nozzle wall thickness = 0.016 m, length of nozzle = 100 mm
07
(b) Discuss the design steps for the calculation of tube side heat transfer coefficient
and pressure drop. 07
Q-5 (a) Explain the types of tray supports. 04
(b) Determine the shell thickness for the entire tower height based on the following
data.
Shell I D – 3500 mm, Working temperature – 180 oC, Working pressure – 2
N/mm2(g), Design temperature – 200 oC, Top disengagement space – 200 mm,
Base chamber height – 3200 mm, Specific gravity of material – 7.7, Permissible
tensile stress – 95 N/mm2, Insulation density – 7700 N/m3, Corrosion allowance –
3 mm, Poisson’s ratio (µ) = 0.3, Modulus of Elasticity of plate material (E) = 1.93
× 105 N/mm2, Insulation thickness – 140 mm, Weight of top elliptical head – 2800
N, Weight of attachment (pipes, ladders & platform) – 1600 N/mm2, Weight of
column – 3 × 106 N, Weight of liquid and tray – 900 N/m2, No. of trays – 60, Tray
spacing – 0.7 m. Neglect the stress created by eccentric and seismic load.
Determine the thickness of distillation column.
10
OR
Q-5 A distillation column subjected to full vacuum is fabricated and installed, having
following specifications.
Shell O D - 2000 mm, Tangent to tangent length of shell - 35 m, Design
temperature - 120 oC, Shell material - SA-283 Grade C, Type of shell plate joint -
Double welded butt joint with 10 % radiography, Height of skirt support - 4 m,
Tray spacing – 0.3 m, No. of trays – 106, Top disengaging space – 1.2 m, Weight
of liquid and tray – 120 kg/m2, Weight of attachment (pipes, ladders & platform) –
150 kg/m, Wind pressure – 130 kgf/m2, Insulation thickness – 500 kg/m3,
Maximum allowable stress of shell plate material at design temperature – 605.22
kgf/cm2, Modulus of elasticity – 2 × 106 kgf/cm2, Poissons ratio – 0.3, Corrosion
allowance – 2 mm, Specific gravity of shell material – 7.865, Weight of top head –
315.55 kg, Stiffening ring of 8 mm thick and 100 mm width are available. Neglect
the stress created by eccentric and seismic load. Determine the thickness of
distillation column.
14
***************
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII (OLD) - EXAMINATION – SUMMER 2017
Subject Code: 170502 Date: 02/05/2017 Subject Name: Process Equipment Design-II Time: 02:30 PM to 05:30 PM Total Marks: 70 Instructions:
1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks.
Q.1 (a) Discuss the design of torispherical head for internal and external design pressure. 07
(b) As a design engineer, which are the various pressure tests carried out for the design
of pressure vessel, explain them in brief?
07
Q.2 (a) Discuss the steps for the design of reinforcement pad for a nozzle. 07
(b) Design the bracket support for vertical cylindrical vessel. The data is given as
follows:
Diameter = 3.0 m
Height = 4.0 m
Clearance of vessel from bottom of vessel to foundation = 1.0 m
Weight of vessel with its content = 60,000 N
Wind pressure (Pw) = 1285 N/m2
Diameter of anchor bolt circle bolt = 3.15 m
No. of bracket = 6
Base plate of bracket = 150 mm × 200 mm
Permissible stress for structural steel
Tensile σt = 140 N/mm2,
Bending σbm = 157.5 N/mm2,
Compressive σcomp = 123.3 N/mm2,
Permissible bearing pressure for concrete = 3.5 N/mm2
Column Support for bracket
Size = 150 x 75
Area of Cross section = 20.88 cm2
Modulus of Section = 19.4 cm3
Radius of gyration = 2.4 cm
Wight = 164 N/m
Height from foundation = 2.25 m
07
OR
(b) Define the following. (i) Elasticity (ii) Brittle fracture (iii) Yield stress (iv)
Resilience (v) Toughness (vi) Creep (vii) Welding joint efficiency factor.
07
2
Q.3 A flat blade turbine agitator with six blades is installed centrally in vertical tank.
The tank is 1.83 m in diameter; turbine is 0.61 m in diameter and is positioned at
0.61 m from the bottom of tank based on the following data.
Height of liquid in tank = 1.83 m
Viscosity of liquid = 15 cP
Density of liquid = 1500 kg/m3
Speed of agitator = 90 rpm
Np=6
Length of agitator shaft between bearing & agitator = 2.1 m
Width of blade = 120 mm
Nos. of baffles at tank wall = 4
Shaft and agitator blade material = IS 2062 Grade ST 42 – W
Ultimate tensile stress = 4200 kgf/cm2
Yield stress = 2300 kgf/cm2
Maximum allowable shear stress in shaft = 550 kgf/cm2
Modulus of elasticity = 19.5 × 105 kgf/cm2
Factor of Safety = 2
Calculate (i) power required for agitation (ii) shaft diameter and (iii) thickness of
agitator blade.
14
OR
Q.3 Discuss the various steps used for design of column supported conical roof. 14
Q.4 (a) Define Gasket seating stress and gasket factor. State the different types of gaskets
and explain any three of them.
07
(b) Explain the function of the following parts for the shell and tube heat exchanger. (i)
Baffles (ii) Tie rods (iiii) Spacers (iv) Expansion joint (v) Tube side pass partition
(vi) Tube sheet (vii) Support.
07
OR
3
Q.4 Design a skirt support for distillation column based on following data.
Diameter of column = 2500 mm
Height of distillation column = 40 m
Maximum weight of vessel, its attachments and contents = 300,000 kg
Type of skirt support = straight cylindrical
Diameter of skirt = 2500 mm
Height of skirt = 5 m
Wind pressure at the bottom of vessel = 100 kg/cm2
Wind pressure at the top of vessel = 128.5 kg/cm2
Material used for skirt support = IS 800, Structural Steel
Allowable tensile stress of material = 1400 kg/cm2
Allowable compressive stress of material = 666 kg/cm2
Allowable bending stress of material = 1575 kg/cm2
Allowable compressive stress of concrete = 35 kg/cm2
Seismic coefficient = 0.08
Joint efficiency = 0.85
Minimum weight of empty vessel = 250,000 kg
Allowable tensile stress of bolt material = 1020.7 kg/cm2
Spacing between stiffeners = 203.2 mm
14
Q.5 The shell & tube heat exchanger has the following data:
Shell inside diameter : 596.9 mm
Tube o.d. = 19.05 mm
Thickness of tube = 1.65 mm
Internal operating pressure of shell side = 3.0 kgf/cm2
Internal operating pressure of tube side = 6.0 kgf/cm2
Allowable stress for shell and tube material = 1054 kgf/cm2
Material of shell : SA 312 TP 304 (seamless pipe)
Material of tube : SS 304
Density of SS 304 = 8000 kg/m3
Mean diameter of gasket = 673 mm
No. of pass on tube side = 2
Depth of pass partition plate = 5 mm
Calculate:
thickness of shell
thickness of tube
thickness of head
blank diameter and weight of head
thickness of tube sheet.
Use only internal design pressure.
Neglect the thickness calculation by external design pressure.
14
OR
Q.5 (a) With a neat sketch discuss various types of Flange facings used in reaction vessel. 07
(b) Write a note on Pressure relieving devices. 07
*************
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII(OLD) • EXAMINATION – WINTER 2016
Subject Code: 170502 Date: 21/11/2016
Subject Name: Process Equipment Design-II
Time: 10:30 AM to 01:30 PM Total Marks: 70 Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) A tower having 4.5 m inside diameter & 8 m length from tangent line to tangent
line of the end closers. Tower is operated under vacuum. Tower shell is
constructed from SA-283 grade-B carbon steel plate, which has yield strength
of 1898.4 kgf/cm2
. Determine the required thickness of shell without stiffeners.
Assume 8 mm thick plate.
07
(b) Define (i) Elasticity (ii) Toughness (iii) Fatigue (iv) Creep (v) Poisson’s ratio (vi)
Moment of inertia (vii) Welding joint efficiency factor. 07
Q.2 (a) Discuss about various types of fabrication technique used for fabrication of
pressure vessel.
07
(b) Explain in detail basic properties of material.
07
OR
(b) Discuss the different types of standard flanges with a neat sketch.
07
Q.3 (a) Explain the stepwise procedure for the design of conical roof with structural
support for storage tank.
14
OR
Q.3 (a) For a ring flange, design a flat ring type gasket and check the bolt size is
appropriate or not.
Internal design pressure = 12 kgf/cm2
Design temperature = 150 oC
Flange material = SA 240 Gr S type 304
Max. allowable stress at design temp = 1020.7 kgf/cm2
Max. allowable stress at atmospheric condition = 1275.9 kgf/cm2
Bolt material = SA 193 Gr B8 type 304
Max allowable stress at 150 oC = 816.5 kgf/cm2
Max. allowable stress at atmospheric condition = 1020.7 kgf/cm2
Bolt size ¾ inch Root area of the bolt = 0.302 in2
Edge clearance = 35 mm Bolt spacing = 61 mm
Gasket material = asbestos composition
Gasket thickness = 1.5875 cm Gasket factor = 2.75
Maximum gasket seating stress = 251.77 kgf/cm2
Shell OD = 900 mm
Shell thickness = 10 mm
14
Q.4 (a) Write a short note on mechanical design of shell and tube heat exchanger.
07
(b) Discuss design of trays and supports for a tray tower.
07
2
OR
Q.4 (a) Discuss in detail the various types of jackets used for heating and Cooling. 07
(b) A vacuum distillation column is to operate under a top pressure 50 mm hg (ab).
Trays of distillation column are supported on periphery rings having 10 mm
thickness and 75 mm width. The OD of column is 1m and the tray spacing is
0.5 m. Check if the support rings will act as effective stiffening rings. The
material of construction is carbon steel and the maximum operating temperature
50°C. If shell thickness is 10 mm, check if this is sufficient. Modulus of
elasticity of carbon steel at 50°C is 200 * 103 N/mm2
07
Q.5 (a) Write a short note on Rupture disks. 07
(b) Write a short note on TEMA Designations.
07
OR
Q.5 (a) Write Short notes: Agitators 07
(b) Discuss the design of bracket or lug support.
07 *************
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII EXAMINATION – SUMMER 2016
Subject Code:170502 Date:07/05/2016 Subject Name:Process Equipment Design-II Time:02:30 PM to 05:30 PM Total Marks: 70 Instructions:
1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks.
Q.1 Design a bracket support for reaction vessel based on following data. Brackets
are welded with outside surface of the reactor shell.
OD of reactor shell = 1052.7 mm, Thickness of the shell =6.35 mm, Height of
the vessel = 2.1524 m, Clearance from vessel bottom to foundation = 0.75 m,
Weight of vessel with contents = 3918.9 kg, Wind pressure = 100 kgf/m2, No of
brackets = 4, Diameter of bolt circle = 1202.7 mm, Size of base plate for
bracket = 150 mm x 150 mm, Height of the C channel from foundation =
2.0264 m, Size of C channel = 150 mm x 75 mm, Area of cross section = 20.88
cm2, Modulus of section = 19.4 cm3, Radius of gyration = 2.21 cm, MOC for
support = IS 800, Max. allowable tensile stress = 1400 kgf/cm2, Max. allowable
compressive stress = 1233 kgf/cm2, Max. allowable bending stress = 1575
kgf/cm2
14
Q.2 (a) Classify the chemical equipment from mechanical design point of view. 07
(b) Define (i) Elasticity (ii) Fatigue (iii) Creep (iv) Resilience (v) Toughness (vi)
Longitudinal stress (vii) circumferential stress. 07
OR
(b) A Reactor (ID = 1000 mm) with hemispherical head at the bottom. Inside
working pressure is 75 kgf/cm2 (g) & working temperature is 70 0C. Reactor is
covered with plain jacket such that 75% length of shell & bottom hemispherical
head is covered with jacket. Cooling water is circulated inside the jacket by
pumping with a centrifugal pump having a shut off discharge pressure 6.0
kgf/cm2(g). The hemispherical head is fabricated from SA-516 Grade 70. The
maximum allowable stress at design temperature is 610 kgf/cm2. Modulus of
Elasticity of plate material (E) = 193 × 103 N/mm2. Poisson’s ratio (µ) = 0.3, ρ
= 7.83 g/cm3, Joint efficiency (J) = 0.85. Take 3 mm corrosion allowance. Find:
(i) Thickness of the head and (ii) weight of the fabricated head.
07
Q.3 Turbine agitators operating in a vessel of 1.6 m diameter is to be designed with
the following data.
Internal design pressure – 5 kgf/cm2, Agitator diameter – 500 mm, Maximum
agitator rpm – 200, Viscosity of liquid – 600 cp, Specific gravity of liquid – 1.2,
Over hang length of shaft – 1200 mm, No. of agitator blade – 6, Elastic limit –
250 N/mm2, Permissible shear stress in shaft – 55 N/mm2, Modulus of elasticity
– 19.5 × 105 kgf/cm2. Calculate (i) power required and (ii) shaft diameter and
(iii) critical speed.
Power number – 8 for NRe < 1500, 6 for 1500 < NRe < 3000, 4.5 for 3000 <
NRe < 4500, 3 for 4500 < NRe < 6000 and 2 for NRe > 6000.
14
OR
Q.3 (a) Discuss in detail the various types of jackets for heating and Cooling. 07
(b) Define gasket seating stress and discuss the various types of gaskets used in
industries. 07
2
Q.4 (a) Explain Normal and Emergency venting for storage vessel. 07
(b) Briefly explain the steps of the general design method for shell and tube heat
exchanger. 07
OR
Q.4 With neat sketch explain the design steps for the conical roof with structural
support. 14
Q.5 (a) Write a short note on Tray supports used for distillation column. 07
(b) With neat diagram write a note on (i) Safety valve (ii) Relief valve 07
OR
Q.5 Determine the shell thickness and stress analysis for the fractionating column
having following specifications.
Shell I.D - 3500 mm, Working temperature – 180 oC, Working pressure – 2
N/mm2 (gauge), Design temperature = 200 oC, Top disengagement space – 200
mm, Base chamber height – 3200 mm, Sp. Gravity of material – 7.7,
Permissible tensile stress – 95 N/mm2, Insulation density – 7700 N/m3,
Corrosion allowance = 3 mm, Poisson ratio = 0.32, Modulus of elasticity E =
1.93 × 105 N/mm2 Insulation thickness – 140 mm, Head type – Eliptical,
Weight of head – 2800 N, Weight of pipe, ladders, platform etc. – 1600 N/m2,
Wind pressure - 1600 N/m2, Weight of liquid and tray – 900 N/m2, Seismic load
and eccentricity are negligible, No. of trays – 60, Tray spacing – 0.7 m.
14
*************
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII EXAMINATION – WINTER 2015
Subject Code: 170502 Date: 07/12/2015 Subject Name: Process Equipment Design-II Time: 10:30am to 1:30pm Total Marks: 70 Instructions:
1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks.
Q.1 Discuss the fo llowing: ( i) int ernal design pressure ( ii) externa l
design pressure ( iii) design temperature ( iv) Classificat ion o f equipment as per IS-2825 (v) Corrosion Allowance (vi) Welding jo int effic iency factor (vii) Radiography.
14
Q.2 (a)
(b)
Discuss the design o f torispher ical head for int ernal and externa l design pressure. Discuss the different types o f standard flanges with a neat sketch.
07
07 OR (b) Discuss the design o f bracket or lug support . 07
Q.3
A storage tank for benzene having fo llowing data: Tank diameter : 6.0 m Tank height : 8.5 m Sp. Gr. Of liquid: 0.88 Conical roof slope – permissible 1 in 5 Super imposed load - 125 kg/m2 Mater ial – carbon steel ( st ructural) Permissible st ress : 980 kgf/cm2 Density o f plate mater ial : 7800 kg/m3 Modulus o f elast icit y: 2 x 106 kg/cm2 Standard plate size = 1 m x 1 m Design the she ll and bot tom. Find out the thickness o f self-support ing conical roof.
OR
14
Q.3 Discuss the var ious steps used for design o f co lumn supported conical roof.
14
Q.4 (a) Discuss with a neat sketch var ious t ypes of jackets. 07
(b) Discuss the method of design for loose flange for react ion vessel. 07 OR
Q.4 The shell & tube heat exchanger has the following data: She ll ins ide diameter : 500 mm Tube o.d. = 15.875 mm Thickness o f tube = 1.65 mm Internal operat ing pressure o f shell side = 3.0 kgf/cm2 Internal operat ing pressure o f tube side = 6.0 kgf/cm2 Allowable st ress for shell and tube mater ial = 1054 kgf/cm2 Mater ial o f shell : SA 312 TP 304 (seamless pipe) Mater ial o f tube : SS 304 Density o f SS 304 = 8000 kg/m3
14
2
Mean diameter of gasket = 550 mm No. of pass on tube side = 2 Depth o f pass part it ion plate = 5 mm Calculate:
(1) thickness of shell (2) thickness of tube (3) thickness of torispher ical heads (4) blank diameter and weight of heads (5) thickness of tube sheet . Use only int ernal design pressure. Neglect the thickness calculat ion by external design pressure.
Q.5 Writ e Short notes: (any two) 1. Agitators 2. Skirt support 3. TEMA Designat ions
14
OR Q.5 A dist illat ion co lumn has fo llowing data:
She ll outer diameter at top = 1800 mm She ll length tangent line to tangent line = 20 meter Internal design pressure = 4 kgf/cm2 Design temperature = 120 0C She ll mater ial = SA 283 Gr C Jo int efficiency = 85% Skirt height = 4 m Tray spacing = 0.3 m (58 t rays) Top disengagement space = 1.2 m Weight of liquid and t ray = 120 kg/m2 Weight of at tachment(pipes, ladders & plat form) = 150 kg/m Wind pressure = 130 kg/m2 Insulat ion thickness = 100 mm Density o f insulat ion = 500 kg/m3 Allowable st ress = 890 kgf/cm2 Modulus o f elast icit y = 2 x 106 kgf/cm2 Poisson’s rat io = 0.3 Corrosion a llowance = 2 mm Sp. Gr. of shell mater ia l = 7.865 Neglect the st ress created by eccentr ic load and seismic load. Calculate the thickness of shell plate for ent ire tower.
14
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1/4
Seat No.: ________ Enrolment No.______________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – SUMMER • 2015
Subject code: 170502 Date: 08/05/2015 Subject Name: Process Equipment Design-II Time: 02.30pm-05.00pm Total Marks: 70 Instructions:
1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks.
Q.1 (a) List the basic mechanical properties which a material should possess and
explain any two of them? 07
(b) A vacuum distillation column is to operate under a top pressure of 50 mmHg(ab). Trays of distillation column are supported on periphery rings having 10 mm thickness and 75 mm width. The OD of column is 1 m and the tray spacing is 0.5 m. Check if the support rings will act as effective stiffening rings. The material of construction is carbon steel and the maximum operating temperature is 500C. If the shell thickness is 12 mm, check if this is sufficient. The modulus of elasticity at 500C is 200 × 103 N/mm2.
07
Q.2 (a) As a design engineer, which are the various pressure tests carried out for the
design of pressure vessel, explain them in brief? 07
(b) A Reactor having inside diameter of 1 meter with torispherical head having a crown radius of 1 meter and knuckle radius of 100 mm at the bottom. Inside working pressure is 10 kgf/cm2 gauge and working temperature is 70°C. Reactor is covered with plain jacket such that 75% lengths of shell and bottom torispherical head are covered with jacket. Cooling water is circulated inside the jacket by using a centrifugal pump having a shut off discharge pressure 6 kgf/cm2(g). The torispherical head is fabricated from SA 516 Grade 70 plate.
1 Maximum allowable stress of this plate material at design temperature
600 kgf/cm2
2 Modulus of Elasticity of plate material
19500 kgf/mm2
3 Poisson’s ratio 0.3
4 Density of plate material 7830 kg/m3
5 Joint efficiency 0.85
6 Corrosion allowance 3 mm
Find: (1) Thickness of the head (2) Weight of this head
07
2/4
OR
Q.2 (b) Why are gaskets used? Write in brief on various types of gaskets? 07
Q.3 (a) Give the function of baffles, tie rod, sealing strip, tube sheet, shell side partition and tube side partition in a heat exchanger.
07
(b) Why is reinforcement pad provided? Outline its design method? 07
OR Q.3 Determine the shell thickness at different height of a storage tank for the
given data:
Storage capacity of the tank =611.11 m3, Density ρ Fluid= 900 kg/m3, joint efficiency J = 0.85, f = 1070 kg/cm2, C.A. = 2, Type of welding joint = double welded butt joint, Available plate = 4 m × 1.5 m, Also calculate the total no. of plate required to fabricate the vessel. Nominal thickness of the standard plates are 5, 6, 8, 10, 12, 14, 16 in mm (use H/D=1.0)
14
Q.4 It is desired to design a bracket support for a vertical cylindrical reaction
vessel installed indoor. Following data are available.
a. Diameter of the vessel = 1.5 m
b. Vessel height = 1.8 m
c. Clearance from vessel bottom to foundation = 1 m
d. Weight of vessel with content = 7500 kg
e. Number of brackets = 4
f. Height of bracket from the foundation = 2.0 m
g. Diameter of anchor bolt circle =1.65 m
h. Base plate dimension for bracket: 14 cm x15 cm
i. Distance between vessel wall and bracket end = 150 mm
j. Gusset plate are 125 mm apart from each other
k. Web plates dimensions for bracket height =0.7071
l. Base plate size = Extends 20 mm on either side of channel
m. Channel size = 150 × 75 (Area = 21 cm2)
n. Modulus of section = 19 cm3
o. Radius of gyration = 2.2 cm
p. Weight = 170 N/m
q. Eccentricity = 7.5 cm
14
3/4
Permissible stresses:
1. Tensile stress = 140 N/mm2
2. Compressive stress = 128 N/mm2
3. Bending stress = 157 N/mm2
4. Permissible bearing pressure of concrete = 5.0 N/mm2
Vessel is kept indoors; Calculate the base plate and gusset plate thickness and thickness of the column base plate.
OR Q.4 (a) Outline the stepwise procedure for the design of Saddle support. 07
(b) What are pressure relief devices? Give advantages and disadvantages of any two of them?
07
Q.5 A distillation column is to be fabricated & installed, having following specifications:
i. Shell O.D. at top = 2000 mm
ii. Shell length tangent line to tangent line = 22 m,
iii. External design pressure =1.003 kgf/cm2
iv. Design temperature = 120 °C
v. Shell Material = SA-283 Grade C, Specific gravity = 7.865
vi. Type of shell plate joint = Double welded butt joint with 10%
radiography (J = 0.85)
vii. Nominal thickness of the standard plates are 8, 10, 12, 14, 16 in mm
viii. Weight of top head= 315.55 kg
ix. Weight of stiffening ring = 41.51 kg
x. Tray spacing = 0.3 m
xi. Top disengaging space = 1.2 m
xii. Weight of one tray plus wt. of liquid over the same =120 kg/m2
xiii. Wt. of attachments (pipes, ladders & platforms) = 150 kg/m
xiv. Wind pressure = 130 kgf/m2
xv. Insulation thickness = 100 mm , Density of insulation = 500 kg/m3
xvi. Maximum allowable stress of shell plate material at design
temperature = 890 kgf/cm2
xvii. Modulus of elasticity = 2 x 106 kgf/cm2
xviii. Poisson’s ration = 0.3
xix. Corrosion allowance
Neglect the stress created by eccentric load and seismic load.
14
4/4
OR
Q.5 (a) Discuss about various safety devices used for pressure vessel. 07
(b) Discuss in detail the various types of jackets used for heating and Cooling. 07
*************
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – WINTER • 2014
Subject Code: 170502 Date: 02-12-2014
Subject Name: Process Equipment Design-II
Time: 10:30 am - 01:30 pm Total Marks: 70 Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) Discuss about various types of fabrication technique used for fabrication of
pressure vessel.
07
(b) A nozzle having I.D 400 mm is fabricated from S.S 316 plate. It is attached by
welding to a vessel having I.D 1500 mm. Internal design pressure is 10 kgf/cm2
and design temperature is 300°C. Maximum allowable stress at design
temperature is 612.4 kgf/cm2. Joint efficiency is 0.85 and corrosion allowance is
1.5 mm for both shell and nozzle. Density of material of fabrication is 7830
kg/m3. Calculate thickness and weight of reinforcement pad.
07
Q.2 (a) It is desired to design a bracket support for a vertical cylindrical reaction vessel.
Following are the data available.
Vessel diameter = 1.5 m
Vessel height = 2.0 m
Clearance from vessel bottom to foundation = 1.0 m
Weight of vessel with contents = 40000 N
No. of brackets = 4
Height of bracket from foundation = 2.0 m
Diameter of bolt circle = 1.65 m
Base plate dimensions for bracket = 14 cm x 15 cm
Distance between vessel wall and bracket end = 150 mm
Gusset plates are 140 mm apart from each other
Web plate dimension for bracket height: cosƟ = 0.707
Permissible stresses:
Tensile stress = 140 N/mm2
Compressive stress = 123.3 N/mm2
Bending stress = 157.5 N/mm2
Assuming wind pressure = 1285 N/m2
Calculate thickness of base plate and thickness of web plate.
07
(b) Discuss about design of tube, tube sheet of shell and tube heat exchanger. 07
OR
(b) Define the following.
a. Elasticity b. Brittle fracture c. Yield stress d. Resilience e. Toughness
f. Creep g. Welding joint efficiency factor.
07
2
Q.3 (a)
A flat blade turbine agitator with six blades is installed centrally in vertical tank.
The tank is 1.83 m in diameter, turbine is 0.61 m in diameter and is positioned at
0.61 m from the bottom of tank. Calculate (i) power required for agitation (ii)
shaft diameter (iii) thickness of agitator blade based on following data.
Height of liquid in tank = 1.83 m
Viscosity of liquid = 15 cp
Density of liquid = 1500 kg/m3
Speed of agitator = 90 rpm
Length of agitator shaft between bearing and agitator = 2.1 m
Width of blade = 120 mm
No. of baffles at tank wall = 4
Ultimate stress = 4200 kg/cm2
Yield stress = 2300 kg/cm2
Maximum allowable shear stress in shaft = 550 kg/cm2
Modulus of elasticity = 19.5 x 105 kg/cm2.
14
OR
Q.3 (a) Explain the statement “Generally jackets are used for coils are used for cooling”.
Discuss various types of jackets and coils.
07
(b) A fixed conical roof storage tank is fabricated from structural carbon steel plate.
Based on the following data find the thickness of conical roof plate and size of
roof curb angle. Storage tank is classified as Class A tank.
Tank diameter = 7 m
Tank height = 5 m
Slope of conical roof = 1 in 6
Superimposed live load on roof = 125 kg/cm2
Modulus of elasticity = 2 x 106 kgf/cm2
Density of plate material = 7800 kg/m3
Poisson’s ratio = 0.3
Thickness of top most course = 10 mm.
07
Q.4 (a) Design a ring flange based on given data
Internal design pressure = 10 kgf/cm2
Design temperature = 150°C
Shell O.D = 900 mm
Basic gasket seating width = 10 mm
Shell thickness = 10 mm
Maximum allowable stress of flange material at atmospheric temperature =
1257.9 kg/cm2
Maximum allowable stress of bolting material at design temperature = 816.5
kg/cm2
Maximum allowable stress of bolting material at atmospheric temperature =
1020.7 kg/cm2
Bolt size = 3/4”
Root mean area of bolt =0.302 in2
Gasket factor = 2.75
Gasket seating stress = 257.77 kg/cm2
Calculate gasket and flange dimensions with no. of bolts and every factor of
flange design.
14
OR
Q.4 (a) Write a note on Pressure relieving devices. 07
3
(b) Discuss design of trays and supports for a tray tower. 07
Q.5 Design a skirt support for distillation column based on following data.
Diameter of column = 2500 mm
Height of distillation column = 40 m
Maximum weight of vessel, its attachments and contents = 300,000 kg
Type of skirt support = straight cylindrical
Diameter of skirt = 2500 mm
Height of skirt = 5 m
Wind pressure at the bottom of vessel = 100 kg/cm2
Wind pressure at the top of vessel = 128.5 kg/cm2
Allowable tensile stress of material = 1400 kg/cm2
Allowable compressive stress of material = 666 kg/cm2
Allowable bending stress of material = 157.5 kg/cm2
Allowable compressive stress of concrete = 35 kg/cm2
Seismic coefficient = 0.8
Joint efficiency = 0.85
Minimum weight of empty vessel = 250,000 kg
Allowable tensile stress of bolt material = 1020.7 kg/cm2
14
OR
Q.5 (a) Discuss design steps for column supported conical roof. 07
(b) Find out thickness of shell of the reactor and thickness of jacket for the
following three available options: (i) Reactor with plain jacket ii) Reactor with
channel jacket iii) Reactor with half coil jacket.
Given data:
Inside diameter of shell = 1500 mm
Inside diameter of jacket = 1600 mm
Shell length = 1500 mm
Diameter of half coil = 75 mm
Width of channel jacket = 75 mm
Internal design pressure of shell = 4 kgf/cm2
Internal design pressure of jacket = 3 kgf/cm2
Design temperature for both shell and jacket =150° C
Maximum allowable stress at design temperature =980 kgf/cm2
Modulus of elasticity = 19 x 105 kgf/cm2
Poisson’s ratio = 0.3
Joint efficiency = 0.85
07
*************
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – SUMMER • 2014
Subject Code: 170502 Date: 03-06-2014
Subject Name: Process Equipment Design-II
Time: 02:30 pm - 05:30 pm Total Marks: 70 Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) Briefly discuss about determination of design pressure and design temperature.
04
(b) Answer the following questions.
i. Give full form of TEMA and HTRI?
ii. Define weld joint efficiency factor. Explain radiography test.
iii. How many brackets are required, if vessel diameter > 5 m? Short vertical
cylindrical vessels are generally supported by bracket support. True or
False?
iv. With neat sketch show crown radius, knuckle radius and straight flange
portion in torispherical head.
v. If Reynolds number > 300, baffles are required in agitated vessel? True or
False? Why?
10
Q.2 (a) A process vessel is to be designed for the maximum operating pressure of 500
kN/m2. The vessel has the nominal diameter of 1.2 m and tangent to tangent length
of 2.4 m. The vessel is made of IS: 2002-1962 Grade 2B quality steel having
allowable design stress value of 118 MN/m2 at working temperature. The
corrosion allowance is suggested to be 2 mm for the life span expected for the
vessel. The vessel is to be fabricated according to class 2 of Indian Standard
specifications which stipulate the weld joint efficiency of 0.85.
i. What is the standard plate thickness to fabricate this vessel?
ii. If a spherical vessel having the same diameter and thickness is fabricated
with the same quality steel, what maximum internal pressure the sphere will
withstand safely?
07
(b) Explain in detail basic properties of material. 07
OR
(b) Describe different methods for fabrication of equipment. 07
Q.3 (a) Prepare a list of different types of standard flanges. Explain with neat sketch any
two standard flanges in detail.
07
(b) Write a short note on mechanical design of shell and tube heat exchanger. 07
OR
Q.3 (a) Explain design procedure for saddle support.
07
(b) Discuss about different types of agitators and their selection criteria. 07
2
Q.4 (a) Calculate the base plate thickness and gusset plate thickness for bracket support.
Data Given:
Weight of vessel with contents = 7 tons, Diameter of vessel = 1.5 m
Height of Vessel = 2 m, Vessel clearance from foundation = 1 m
Height of bracket from foundation = 2 m, Number of brackets = 4
Bolt circle diameter=1.6 m, Permissible bending stress for the material=160 N/mm2
Base plate size = 15 cm X 15 cm, Space between gusset = 12 cm
Height of gusset vessel = 120 cm
Vessel is kept inside the room.
07
(b) Write a short note on tray support. 07
OR
Q.4 (a) A fixed conical roof storage tank is fabricated from structural carbon steel plate
(IS-2062). Based on given following data find out the thickness of conical roof
plate. Storage tank can be classified as ‘Class A tank’.
Data Given:
Tank diameter = 7 m, Tank height = 5 m
Slope of conical roof = ‘1 in 6’, Superimposed live load on roof = 125 kgf/m2.
Modulus of Elasticity = 2 x 106 kgf/cm
2, Density of plate material = 7800 kg/m
3.
Poisson’s rtion = 0.3, Thickness of topmost shell course = 10 mm
07
(b) Write a short note on relief valves. 07
Q.5 A turbine agitator is used in a process vessel of 1.5 m diameter, calculate the horse
power and shaft diameter.
Data given:
Tank diameter = 1.5 m, Impeller diameter = 0.5 m
Impeller speed = 120 rpm, Density of liquid = 1250 kg/m3.
Viscosity of liquid = 250 cp
Overhang of the shaft between the bearing and the agitator = 2 m
Elastic limit in tension = 2500 kg/cm2, Modulus of elasticity = 2 x 10
6 kgf/cm
2.
f = 50 kgf/cm2, Np = 6 for NRe < 4500, Np = 5 for NRe > 4500
14
OR
Q.5 From the stress analysis, calculate the shell thickness of a tall fractionating column.
Data given:
Design pressure = 5 kgf/cm2, Design temperature = 200 °C.
Shell ID = 2 m, Tray spacing = 0.75 m
Total height of vessel = 18 m, Top chamber height = 1 m
Bottom chamber height = 1.5 m, Tray spacing = 0.75 m
Material of construction = carbon steel, M. O. C. = C. S., Sp. Gr. = 7.7
f = 1000 kgf/cm2, tins = 50 mm, Density = 750 kgf/cm
2.
Weight of attachment = 100 kg/m, Weight of liquid and tray = 80 kg/m2.
Wind pressure = 150 kg/m2, Corrossion allowance = 2 mm
Head: Elliptical
Weight of top head = 4 tons, Weight of bottom head = 4 tons
Poisons ratio = 0.3, Young’s modulus = 1.95 x 106 kgf/cm
2.
Tower is located at a non-seismic zone and eccentric loads are negligible.
14
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1/3
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – SUMMER 2013
Subject Code: 170502 Date: 24-05-2013
Subject Name: Process Equipment Design – II
Time: 02.30 pm - 05.30 pm Total Marks: 70 Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) Design a shell for fixed conical roof cylindrical storage tank for following
data:
Tank diameter = 30 m Tank height = 18 m
Specific gravity = 1.24 Slope of conical roof = 1/6
Super imposed live load = 1250 N/m2
MOC – Carbon steel
Maximum allowable stress f = 157.5 N/mm2
Density = 7.8 gm/cc Modulus of Elasticity E = 2 x 105
N/mm2
Corrosion Allowance = 2 mm
Standard plate size available is 6300 x 1800 mm
Type of butt joint = double welded butt joint with 85% efficiency.
07
(b) Describe general design steps for shell and tube heat exchanger. 07
Q.2 (a) Design the shell of pressure vessel subjected to internal operating pressure of
7.7 atmg
Inside dia. 3 m;
Operating Temperature 400° C;
MOC – CS grade 70 [UTS: 418 N/mm2, FOS = 3];
E – 185*103 N/mm
2; µ= 0.32; corrosion Allowance = 2 mm
Weight of vessel = 5520 kg;
Maximum wind load applicable to vessel = 9000 N.m;
Torque due to offset of piping = 625 N.m;
07
(b) Design a bracket support for reaction vessel based on following data.
Brackets are welded with outside surface of the reactor shell.
OD of reactor shell = 1.3 m Thickness of the shell =12 mm
Height of the vessel = 2.5m
Clearance from vessel bottom to foundation = 1 m
Weight of vessel with contents = 3750 kg
Wind pressure = 130 kgf/m2
No of brackets = 4 Diameter of bolt circle = 1.51 m
Size of base plate for bracket = 150 mm x 150 mm
Size of gusset plate for bracket = 150 mm x 150 mm
Height of the C channel from foundation = 2.625 m
Size of C channel = 150 mm x 75 mm
Area of cross section = 22 cm2 Modulus of section = 24.6 cm3
Radius of gyration = 2.43 cm
MOC for support = IS 800
Max. allowable tensile stress = 1400 kgf/cm2
Max. allowable compressive stress = 1233 kgf/cm2
Max. allowable bending stress = 1575 kgf/cm2
07
OR
(b) Find the thickness of a straight cylindrical skirt support for distillation
column based on following data.
Diameter of column = 2500 mm
07
2/3
Height of distillation column = 40 m
Max. wt of vessel, its attachment & contents = 300000 kg
Diameter of skirt =2500 mm
Height of skirt = 5 m
Wind pressure at the top of column =128.5 kgf/m2
Material used for skirt support = IS 800 structural steel
Max. allowable tensile stress = 1400 kgf/cm2
Max. allowable compressive stress = 666 kgf/cm2
Max. allowable bending stress = 1575 kgf/cm2
Seismic coefficient =0.08
Minimum wt of empty vessel = 250000 kg
Q.3 (a) Compare head thickness for torrispherical, elliptical and hemispherical heads
using following data:
Operating pressure = 15 Atm;
Crown radius = 1000 mm; Knuckle radius = 100 mm;
MOC – CS (f = 142 N/mm2, CA = 2 mm);
J = 0.85; Shell ID = 1000 mm;
Inside depth of the elliptical dish = 200 mm
07
(b) Discuss the steps for the design of reinforcement pad for a nozzle. 07
OR
Q.3 For a ring flange, design a flat ring type gasket and check the bolt size is
appropriate or not.
Internal design pressure = 12 kgf/cm2
Design temperature = 150 oC
Flange material = SA 240 Gr S type 304
Max. allowable stress at design temp = 1020.7 kgf/cm2
Max. allowable stress at atmospheric condition = 1275.9 kgf/cm2
Bolt material = SA 193 Gr B8 type 304
Max allowable stress at 150 oC = 816.5 kgf/cm
2
Max. allowable stress at atmospheric condition = 1020.7 kgf/cm2
Bolt size ¾ inch Root area of the bolt = 0.302 in2
Edge clearance = 35 mm Bolt spacing = 61 mm
Gasket material = asbestos composition
Gasket thickness = 1.5875 cm Gasket factor = 2.75
Maximum gasket seating stress = 251.77 kgf/cm2
Shell OD = 900 mm
Shell thickness = 10 mm
14
Q.4 (a) A fixed conical roof storage tank is fabricated from structural carbon steel
plate. Based o the following data find the thickness of conical roof plate and
size of roof curb angle. Storage tank is classified as Class A tank.
Tank diameter = 7 m Tank height = 5 m
Slope of conical roof = 1 in 6
Superimposed live load on roof = 125 kgf/m2
Modulus of elasticity =2 x 106 kgf/cm
2
Density of plate material = 7800 kg/m3
Poisson’s ration = 0.3 Thickness of top most course =10 mm
07
(b) Calculate the weight of tubes and tube sheet for AEM type shell and tube
heat exchanger using following data:
Inside diameter of shell = 580 mm Thickness of the shell =5 mm
Tube diameter = 19.05 mm Number of tubes required = 446
Minimum thickness required according to TEMA standards = 1.5 mm
Length of the shell = length of tube =2.4384 m
Operating pressure on tube side = 600 kPa
Operating pressure on shell side = 1 atm
MOC of tubes = SS 304
Maximum allowable stress at op. temperature (150 oC)= 104 N/mm
2
07
3/3
MOC of tube sheet =SA 240 Gr S plates
Maximum allowable stress at operating temperature = 110N/mm2
Depth of pass partition groove = 5 mm
Gasket mean diameter for fixing of the tube sheet = 673 mm
Density of MOC = 8000 Kg/m3
Tube sheets are integral part of the shell of HE.
OR
Q.4 (a) Discuss the design of trays and tray supports for a tray tower. 07
(b) Describe the steps for structurally supported roof design. 07
Q.5 A flat blade turbine agitator with six blades is installed centrally in vertical
tank. The tank is 1.5 m in diameter; turbine is 0.5 m in diameter. Based on
the given following data, Calculate (1) Power required for agitator, (2) shaft
diameter.
Height of liquid in tank = 1.5 m
Viscosity of liquid = 20 cp Density of liquid = 1200 kg/m3
Speed of agitator = 120 rpm
Length of agitator shaft between bearing and agitator = 2 m
Width of blade Rb = 120 mm
No. of baffles at tank wall = 4
Shaft & agitator blade material = IS 2062 Gr ST 42 W
Ultimate tensile stress = 4200 kgf/cm2
Max. allowable shear stress in shaft = 550 kgf/cm2
Modulus of elasticity = 19.5 105 kg/cm
2
For NRe >=10000, Np =6 and NRe <10000, Np =5
14
OR
Q.5 (a) Write a short note on “Pressure Relieving Devices”. 07
(b) Determine the shell thickness for the entire tower height based on the
following data:
Shell diameter = 3500 mm
Working pressure = 2 N/mm2
Design temperature = 200 oC
Base chamber height = 3200 mm
Top chamber height = 2000 mm
Feed chamber height = 800 mm
Sp. Gr. Of the material = 7.7
Permissible tensile stress = 95 N/mm2
Insulation density = 7700 N/m3
Corrosion allowance= 3 mm
Poisson’s ratio = 0.3 Density of MOC = 1.93 x103 kg/m
3
Insulation thickness = 148 mm
Weight of head = 2800 N
Weight of attachments (pipes, ladders, platforms) = 1600 N/m
Weight of column = 3x106 N
Weight of tray and liquid = 900 N/m2
Wind pressure =1600 N/mm2
Neglect the seismic load and eccentricity
Number of trays = 60 Tray spacing = 0.7 m
Joint efficiency is 85 %.
07
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