gujarat technological university -...

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

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1


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:


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

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1


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:


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

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1


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.


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


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


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:


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

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1


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:


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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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:


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

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1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – WINTER • 2014

Subject Code: 170502 Date: 02-12-2014


Time: 10:30 am - 01:30 pm Total Marks: 70 Instructions:




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.


Viscosity of liquid = 15 cp

Density of liquid = 1500 kg/m3


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


Design temperature = 150°C

Shell O.D = 900 mm

Basic gasket seating width = 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.



Maximum weight of vessel, its attachments and contents = 300,000 kg

Type of skirt support = straight cylindrical

Diameter of skirt = 2500 mm


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


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


07

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1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – SUMMER • 2014



Time: 02:30 pm - 05:30 pm Total Marks: 70 Instructions:




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


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – SUMMER 2013


Subject Name: Process Equipment Design – II

Time: 02.30 pm - 05.30 pm Total Marks: 70 Instructions:




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.


07

2/3


Max. wt of vessel, its attachment & contents = 300000 kg

Diameter of skirt =2500 mm


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.



Flange material = SA 240 Gr S type 304

Max. allowable stress at design temp = 1020.7 kgf/cm2


Bolt material = SA 193 Gr B8 type 304

Max allowable stress at 150 oC = 816.5 kgf/cm

2


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


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.


Viscosity of liquid = 20 cp Density of liquid = 1200 kg/m3


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


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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