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By: Baher EL ShaikhBy: Baher EL ShaikhMechanical EngineerMechanical Engineer
EMetahnexEMetahnex
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Shell and tube heat exchangers are one of the most common equipment found in all plants
How it works?
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Heat Exchanger
Cooler
Heater
Condenser
Reboiler
Both sides single phase and process stream
One stream process fluid and the other cooling water or air
One stream process fluid and heating utility as steam
One stream condensing vapor and the other cooling water or air
One stream bottom stream from a distillation column and the other a hot utilityor process stream
Classification according to service .
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Code
Standard
Specifications
Is recommended method of doing something
ASME BPV – TEMA
is the degree of excellence requiredAPI 660-ASME B16.5–ASME B36.10M–ASME B36.19-ASME B16.9–ASME B16.11
Is a detailed description of construction, materials,… etc Contractor or Owner specifications
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2- Channel3- Channel Flange4- Pass Partition5- Stationary Tubesheet6- Shell Flange7- Tube
8- Shell9- Baffles
10- Floating Head backing Device11- Floating Tubesheet12- Floating Head13- Floating Head Flange
14 –Shell Cover
1- Channel Cover
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Front Head TypeFront Head Type
A - Type B - Type C - Type
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Shell TypeShell Type
E - Type F - Type
J - TypeK - Type
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Rear End Head TypesRear End Head Types
M - Type S - Type T - TypeFixed Tubesheet Floating Head Pull-Through
Floating Head
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U-Tube Heat ExchangerU-Tube Heat Exchanger
Fixed Tubesheet Heat ExchangerFixed Tubesheet Heat Exchanger
Floating Tubesheet Heat exchangerFloating Tubesheet Heat exchanger
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AES11
AKT12
Terminology Design data
Material selection
Codes overview
Sample calculations
Hydrostatic test
Sample drawing
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ASME TEMA API MAWP MDMT PWHT NPS – DN – NB – NPT Sch - BWG
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Heat Exchanger Data Sheet :
Design pressure Design temperature Dimensions / passes Tubes ( dimensions, pattern) Nozzles & Connections
TEMA type
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Baffles (No. & Type)
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A – Yield StrengthA – Yield Strength
B – Tensile StrengthB – Tensile Strength
C – Rupture pointC – Rupture point
AB
C
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Creep Strength a slow plastic strain increased by time and temperature (time and
temperature dependant) for stressed materials
Fatigue Strength The term “fatigue” refers to the situation where a specimen breaks
under a load that it has previously withstood for a length of time
Toughness The materials capacity to absorb energy, which, is dependant upon
strength as well as ductility
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ASME code OverviewASME code Overview
ASME BPV code
Sec.I Power Boilers
Sec.II Materials
Sec.III Nuclear Fuel Containers
Sec.IV Heating Boilers
Sec. V Non Destructive Examination
Sec. VI Operation of heating boilers
Sec. VII Operation of power boilers
Sec. VIII Pressure vessels
Sec. IX Welding and Brazing
Sec. X Fiber-Reinforced plastic PV
Sec. XI Inspection of nuclear power plant
Sec. XII Transport tanks
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ASME code overviewASME code overview Sec. II: Materials
Part A : Ferrous material specifications Part B : Non-Ferrous material specifications Part C : Specifications of welding rods, electrodes and filler metals
Part D : Properties
Sec. VIII: Rules of construction of pressure vessels
Division 1 : 3 Subsections + mandatory Annex + non mandatory Annex
Division 2: Alternative rules Division 3 : Alternative rules of high pressure
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ASME code overviewASME code overview
TEMA code overviewTEMA code overview TEMA classes:
Class R: Generally severe requirements for petroleumand related processing applications
Class C: Generally moderate requirements of commercialand general processing applications
Class B: Chemical Process service
TEMA subsections 10 subsection
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Sample CalculationsSample Calculations Shell thickness calculations under Internal Pressure:
t : Min. Required Shell Thickness P : Design Pressure of Shell Side S: Max. Allowable Stress of Shell Material R: Shell Inside Radius (corroded conditions) E : Joint Efficiency CA: Corrosion Allowance UT: Under Tolerance (if applicable)
PR .SE – 0.6 P
+ CAt = + UT
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Sample CalculationsSample Calculations Channel thickness calculations under Internal Pressure:
t : Min. Required Channel Thickness P : Design Pressure of Tube Side S: Max. Allowable Stress of Channel Material R: Channel Inside Radius (corroded conditions) E : Joint Efficiency CA: Corrosion Allowance UT: Under Tolerance (if applicable)
PR .SE – 0.6 P
+ CAt = + UT
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Sample CalculationsSample Calculations Body Flanges:
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Sample CalculationsSample Calculations Body Flanges:
Trial and error calculations Gasket seating conditions
No. of bolts and size Bolt circle diameter Inside and outside diameters
Check min. and max. bolt spacing
Detailed analysis of the flange Forces calculations Moment calculations Stresses calculations
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Operating conditions
Sample CalculationsSample Calculations Precautions in body flanges design and installations:
Pairs of flanges Bolt holes shall straddle center line Corrosion Allowance
Bolts shall be multiple of 4 Bolting shall be allowed to be removed from either side
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Calculated thickness not include the RF
Cladding
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Sample CalculationsSample Calculations Nozzles and standard flanges:
Flange Rating (ASME B16.5)
Nozzle neck thickness calculations
Area replacement calculations
Sample
Impingement protection
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Sample CalculationsSample CalculationsTubesheet:
• Tubesheet is the principal barrier between shell side and tube side
• Tubes shall be uniformly distributed
• Tubesheet thickness shall be designed for both sides
• Tubesheet shall be designed for bending stresses and shear stresses
• Corrosion allowance
• Made from around flat piece of metal with holes drilled for the tubes
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Sample CalculationsSample CalculationsTubesheet:
• Tubesheet thickness for bending
T: Effective tubesheet thickness
S: Allowable stress
P: Design pressure corrected for vacuum if applicable at the other side
η: Ligament efficiency
For Square pattern
For Triangular pattern
G: Gasket effective diameter
F: Factor
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Sample CalculationsSample CalculationsTubesheet:
• Tubesheet thickness for Shear:
T: Effective tubesheet thickness
DL: Effective diameter of the tube center parameter DL=4A/C C: Perimeter of the tube layout A: Total area enclosed by the Perimeter C
P: Design pressure
S: Allowable stress
do: Outside tube diameter
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Tube-to-Tubesheet Tube-to-Tubesheet jointjointExpanded
Seal welded
Strength welded
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Hydrostatic TestHydrostatic Test
Test pressure : 1.3 X MAWP
Test Procedure
Gasket change
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Sample drawingSample drawing
Construction drawing is the design output
Sample drawing 1 Sample drawing 2
