Team HELA Third Report (1)

SPRING 2013

Date Submitted: May 1, 2013

Team Name: HELATeam Members:

Robert MaduroAdolfo Leyva

Ricardo GonzalezLuis M. Avila

Heat Exchanger Learning ApparatusReport

MECT 4275

Table of Contents1. Abstract...............................................................................................................................................4

2. Executive Summary.............................................................................................................................5

3. Introduction.........................................................................................................................................6

3.1. What is a Heat Exchanger?..........................................................................................................6

3.2. Shell and Tube Heat Exchangers..................................................................................................6

4. Objective.............................................................................................................................................8

5. Research..............................................................................................................................................9

6. Design Problem.................................................................................................................................11

7. System Components..........................................................................................................................14

7.1. Tanks..........................................................................................................................................14

7.2. Bench Selection.........................................................................................................................14

7.3. Pumps........................................................................................................................................15

7.4. LabVIEW.....................................................................................................................................17

7.5. Temperature Sensor..................................................................................................................18

7.6. Heat Source...............................................................................................................................20

8. Design Objective................................................................................................................................22

9. Design Procedure of Heat Exchanger................................................................................................23

10. Design Criteria...............................................................................................................................25

10.1. Tube Layout Configuration.....................................................................................................26

11. Thermal Analysis of the Heat Exchanger........................................................................................30

11.1. Thermal Sample Calculations.................................................................................................32

11.2. Case 1 HTRI Results................................................................................................................34



12. Mechanical Design of the Heat Exchanger.....................................................................................37

12.1. Mechanical Calculations:.......................................................................................................38

12.1.1. Shell Cylinder Calculations.................................................................................................38

12.1.2. Tube sheet Calculations.....................................................................................................40

12.1.3. Flange Calculations............................................................................................................41

13. Gantt Chart:...................................................................................................................................42

14. Cost Estimation:.............................................................................................................................43

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Works Cited...............................................................................................................................................44

Appendix 1: Quote from American Eagle Oilfield......................................................................................45

Appendix 2: Echoscan LLC Quotation........................................................................................................46

Appendix 3: Total Dynamic Head Calculations..........................................................................................47

Appendix 4: HTRI Final Results..................................................................................................................50

Appendix 5: Thermal Calculations to Compare with HTRI Results.............................................................65

Appendix 6: Detail of Tube Sheet Calculations..........................................................................................68

Appendix 7: Flange Calculations................................................................................................................73

Appendix 8: Heat Exchanger Drawings......................................................................................................85

Appendix 9: Total Working Hours for the Project......................................................................................93

Table of Figures

Figure 1 - Shell and Tube Heat Exchanger...................................................................................................5Figure 2: Application of Heat Exchanger Technologies................................................................................9Figure 3: Demand for Mechanical Engineers (4 Years)..............................................................................10Figure 4: Total Dynamic Head....................................................................................................................14Figure 5 - Flow Diagram for heat exchanger design process.....................................................................22Figure 6 - HELA preliminary Case 1............................................................................................................25Figure 7 - HELA preliminary Case 2............................................................................................................26Figure 8 - HELA preliminary Case 3............................................................................................................27Figure 9 - Flow Streams.............................................................................................................................29Figure 10 - Slip On and Weld Neck Flanges................................................................................................35

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1. Abstract

Team HELA is designing and will manufacture a Heat Exchanger Learning Apparatus that will

provide students with a comprehensive study of heat exchangers and the various parameters that affect

its performance. The apparatus will help bridge the gap between theoretical knowledge and hands on

experience of heat exchangers at the University of Houston’s College of Technology. The Heat Exchanger

Learning Apparatus will be designed to be part of the lab curriculum for the Mechanical Engineering

Technology Degree Program. Currently Team HELA is in the process of designing the main component of

the apparatus, the heat exchanger, and selecting the other components that will make up the

apparatus. Once the design is finalized the allocation of funds will proceed by finding sponsors that are

willing to contribute to the advancement of knowledge of the students.

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2. Executive Summary

Team HELA will design a Heat Exchanger Learning Apparatus for future use in the lab of the

College of Technology. Students will be able to complete a full lab with hands on experience that will be

incorporated into their course curriculum. Currently, there is no lab equipment that students can use to

visually learn the fundamentals of a heat exchanger system and its internal components. Most

educational institutions that offer engineering courses in thermodynamics and who specialize in heat

exchangers are only capable of teaching there students the theoretical knowledge.

Heat exchangers are devices that provide the flow of thermal energy between two or more

fluids at different temperatures. Team HELA has decided to design and manufacture a Shell and Tube

heat exchanger. In order to get a good idea of what is available on the market; Team HELA has

researched products offered by other companies similar to the one the team is proposing.

The project will consist of a Heat Exchanger Learning Apparatus that will have interchangeable

components and parameters that can be used by students in the Mechanical Engineering Technology

department at University of Houston. The apparatus can be used in classes such as Fluids Mechanics or

Elements of Plant Design. This product will allow students to obtain first-hand experience handling

important equipment such as a shell and tube heat exchanger and its components. The main

components that were needed for the preliminary design were the pumps, tanks, electrical components,

LabVIEW, and sensors.

The very first step in the design process was to identify the problem. Once the problem was

recognized and all the parameters were set, the preliminary selection of the configuration was selected.

The thermal analysis and mechanical design followed and was completed by the team.

For Team HELA the main goal was to bridge the gap between theoretical knowledge and hands

on experience with heat exchangers at the University of Houston’s College of Technology.

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3. Introduction

3.1. What is a Heat Exchanger?

Heat exchangers are devices that provide the flow of thermal energy between two or more

fluids at different temperatures. These fluids must come into thermal contact for this principle to work.

Heat exchangers are used in a wide variety of applications in various industries. The reason for their

abundance is that heat transfer is vital for many systems to work optimally. Some tasks that heat

exchangers can accomplish include: heating a cooler fluid by means of a hotter fluid, reducing the

temperature of a hot fluid by means of a cooler fluid, or boiling a liquid by means of a hotter fluid. The

transfer of thermal energy always flows from the higher temperature system to the lower temperature

system.

Although heat exchangers can come in any shape and size imaginable, the construction of most

heat exchangers falls into one of two categories: shell and tube or plate. Plate heat exchangers utilize

plates to separate hot and cold fluids which alternate between each plate. Baffles are used to direct the

flow of the fluids between the plates. Because of the inability to reliably seal the large gaskets between

each of the plates, plate type heat exchangers are not widely used. Out of the two, the most common

type of heat exchanger construction is the shell and tube.

3.2. Shell and Tube Heat Exchangers

For Shell and Tube heat exchangers, multiple tubes are installed in a container known as a shell.

A tube sheet separates the tube side fluid from the shell side fluid at the ends of the tubes, which are

either press-fitted or welded into the tube sheet. Support plates in the shell act as baffles to direct the

flow of fluid within the shell back and forth across the tubes. Shell and tube heat exchangers come in

different forms and are classified based on the stationary head, shell, and rear head. The main

components of a shell and tube heat exchanger can be seen in Figure 1.

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Figure 1 - Shell and Tube Heat Exchanger

The tube sheet is an important component of the heat exchanger because it carries the loads

and stresses applied from the tubes. During the mechanical stage of the design, it is important to select

the appropriate thickness of the tube sheet. The baffles are used to create a dynamic flow pattern

through the shell and force the fluid to spend more time in contact with the inner tubes. The bundle is

the inner assembly of internal components and is composed of tubes, baffles, tie rods, spacers, sliding

bars, and tube sheet. The tie rods thread through the baffles and are bolted to the tube sheets; spacers

(large diameter tubes) are placed in between the baffles to properly position them in the shell. Sliding

bars are sometimes placed in the bottom portion of the tube sheets to allow the bundle to slide when

taking the exchanger apart or putting it back together.

One of the biggest advantages of using a shell and tube heat exchanger is that they’re the

simplest to manufacture and the most cost effective.

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4. Objective

Team HELA will design a Heat Exchanger Learning Apparatus for future use in the lab of the

College of Technology. Currently, there is no lab equipment that students can use to visually learn the

fundamentals of a heat exchanger system and its internal components. Students will be able to

complete a full lab with hands on experience that will be incorporated into their course curriculum. The

system will have a control panel that will be able to change various parameters and acquire necessary

experimental data. Since heat exchangers are very common in the petroleum industry, the control panel

will be designed with current industry technology in mind to give students a first-hand experience of

what they may encounter in the field. The system will consist of a one pass shell and tube heat

exchanger with different interchangeable U-tube bundles, which will show the varying performance of

each as they are utilized with different numbers of tubes and baffles. The user will be able to control the

flow rates of the two pumps that will be used via the control panel. Electronic sensors will be fitted to

measure the flow rates of the hot and cold water streams. In addition, the control panel will be able to

regulate the temperature of the heat source. The inlet and outlet temperatures of the hot and cold fluid

will be registered by electronic sensors as well. Because there are so many parameters that the students

can manipulate via the control panel, they will have the opportunity to fully understand the heat

exchanger system from head to toe. The lab that will coincide with the system and doing so will

challenge the students on their knowledge of fluid dynamics, thermodynamics, and elements of plant

design.

Students will have the ability to obtain quantitative results from the heat exchanger learning

apparatus. Some examples of the quantitative results that the students will have to calculate are: heat

transfer and heat loss for an energy balance study, log mean temperature difference, heat transfer

coefficients, and pressure drop to compare with the experimental result. Furthermore, students will also

be able to study the effect of flow rate on the heat transfer rate.

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5. Research

In order to get a good idea of what is available on the market; Team HELA has researched

products offered by other companies similar to the one the team is proposing. SOLTEQ offers various

pieces of equipment for engineering and research. They offer a bench type heat exchanger training

apparatus that was designed to allow students to get familiarized with different types of heat

exchangers. The control panel offered with the system is very primitive and can only control the

temperature of the heat source. The apparatus offered by SOLTEQ only gives students the opportunity

to see the heat exchangers operate, but fails to give the students an understanding of the inner

workings. However, HELA team’s goal is to design an apparatus that students will be able to take apart

and interchange the bundles to visually see the internal components of a shell and tube heat exchanger.

SOLTEQ has been contacted via email inquiring for a quote; since SOLTEQ is overseas, they redirected us

to their sister company in the states, American Eagle Oilfield Services and Supplies. The quote provided

by American Eagle Oilfield Services was $22,750 for the apparatus. The information that was gathered

during the research enables the team to optimize both the design and economics of the project. The

official proposal received from SOLTEQ is attached in the Appendix 1: Quote from American Eagle

Oilfield of this report.

Another US company that was contacted by team HELA was Echoscan LLC, an educational tools

company that has been in the industry since 1980. On the first contact Echoscan sent a catalog with all

the educational tools that they offer. The one that is similar to the idea proposed by the HELA team is

the TD 078 Multi Heat Exchanger. This apparatus consist of three different heat exchangers similar to

the one introduced by SOLTEQ with similar weaknesses. With this apparatus, students don’t have the

ability to understand and visualize the internal components of the heat exchangers. Additionally, the

control system also does not reach the expectations of team HELA because it does not use the latest

technology that is currently being used in the industry. The quote received from the sales manager,

David Ostem, was USD $24,995.00. One of the goals of team HELA is to reduce the price and make it

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attainable for the university. The quote acknowledged from Echoscan LLC is attached at the end of this

report and is labeled as Appendix 2: Echoscan LLC Quotation.

Researching different pieces of equipment has led to ideas on how Team HELA can improve its

design, set goals to develop a better training apparatus, and cut down on manufacturing cost

significantly.

The HELA team also contacted the lab director, Mr. Gordon, on any guidelines that needed to be

included in the design. He proposed to take into consideration the door’s width to avoid project

disassembly and reassembly. In addition, portability and compatibility with the limited school’s 110V

power supply need to be considered. Doctor El Nahas, faculty of the College of Technology and in charge

of the Plant Design class, has also been presented with Team HELA’s heat exchanger proposal. He

stated that the idea could be useful, and the creation of a new experiment would provide a positive

effect to the course.

More products similar to the one being proposed by Team HELA will be researched to get a well-

rounded idea of what can be achieved and improved upon. A group member is currently working for a

company that designs and manufactures heat exchangers. A visit to the company has been scheduled so

the team may observe first-hand the various processes related to building a heat exchanger. His

supervisor will be asked to be an industry mentor and an aid to our team.

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6. Design Problem

Heat exchangers are fundamental in the operation of chemical and mechanical systems. They

serve the function of rejecting or gaining heat. Heat exchangers are found in common applications such

as radiators, internal combustion engines, boilers, condensers, and HVAC systems. They play a crucial

role in every industry ranging from transportation, household, energy, national defense, electronics, and

farming sectors (Figure 1).

Figure 2: Application of Heat Exchanger Technologies

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Nationally, the demand for trained engineers has remained above that of other professions. The

demand for mechanical engineers has increased by 74% since of March of 2011, with over 15,400 new

job postings. Most of the metropolitan areas have seen an increase in the growth since the recession, a

key factor affecting the job market. The U.S. Department of Labor expects Americans to need as many as

87,000 new mechanical engineers in the next four years.

Figure 3: Demand for Mechanical Engineers (4 Years)

Most educational institutions that offer engineering courses in thermodynamics and who

specialize in heat exchangers are only capable of teaching their students the theoretical knowledge.

These institutions do not have the resources for providing their students with equipment or apparatuses

that are designed to teach the inner workings of such fundamental components as heat exchangers.

Since students have very limited access to these educational apparatuses they are not going to be able

to reach their full potential in their respective field.

The goal to be achieved with this product is to develop an apparatus that educational

institutions are going to embrace as a fundamental tool in teaching the complexity of a heat exchanger.

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The design and manufacturability of the apparatus needs to be capable of bridging the gap between the

theoretical and practical. Various milestones need to be addressed to make a functional and appealing

product in the educational market. The fundamental objective of the apparatus is to be an educational

tool that is going to enable students to obtain an in-depth knowledge of the different components and

operations of heat exchangers. The second goal of the project is to develop a product that is economical

for the consumer. The product has to be relatively economical to ensure that educational institutions

include it as a teaching tool in their classrooms. The final objective is for it to be user friendly and

require low amounts of maintenance during the operation cycle. Achieving these three goals will enable

this product to fill the void that institutions have faced over the past century.

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7. System Components

This section of the report introduces all the components needed for the heat exchanger to

operate. The main components that were needed for the preliminary design were the pumps, tanks,

electrical components, LabVIEW, and sensors.

7.1. Tanks

There were several criteria that were taken into account in the selection process for the best

suitable candidate. The tank needed to be able to contain the water that was going to be circulating

throughout the apparatus. The key aspects that had the greatest impact on the selection process were

the 15 gallon capacity, dimensions, material, and price. Most of the tanks that were on the market were

designed as fuel tanks or fuel cells. Also, most were able to hold 15 gallons and were constructed out of

non-corrosive materials such as aluminum or stainless steel. The prices ranged from $180 to $275;

which was reasonable since the cost of the raw material they were composed of was expensive. The

only disadvantage that was found was that they were designed for automobiles and none of the fittings

would have fit our application. The tanks would have needed modifications to fit our application by

drilling and welding new fittings. After a long deliberation the decision was made to manufacture our

own tanks. This would be most beneficial and feasible, since they are going to be designed around our

specific application.

7.2. Bench Selection

The bench is where all the components of the heat exchanger will be attached. The selection

process for a bench had several key components which included: the load it could support, mobility,

material, and cost. Most of the benches that were in the market that fit our application were used in the

medical or restaurant industry. Since they were used in industries where hygiene is of crucial

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importance, they were made out of stainless steel. This makes it easy to clean and corrosion resistant.

All four of the proposed candidates came with casters, which enabled them to be mobile. The dimension

of the bench was also a key factor because it needed to fit within a 36 in. doorway, while still being able

to hold all of the equipment. From our calculations it was determined that the weight of all the

components would be around 600 lbs. After deliberating, the decision was made to incorporate the AB

Restaurant Equipment WTSG-30X48C into the project. The manufacturer was contacted and they

confirmed that the bench could support up to 800 lbs. Also that each caster was rated at 250 lbs.; these

ratings met the load criteria set forth by the team. Another benefit in choosing this bench was that it

was one of the most economical. The whole bench was composed of stainless steel. This factor will

increase the life of the apparatus and its aesthetics.

7.3. Pumps

There are four important factors that were taken into account for pump selection:

feet of head

max fluid temperature to transport

power requirements

In order to start the pump selection the Total Dynamic Head (TDH) was calculated. Figure 4 shows

the proposed configuration used to calculate TDH for the apparatus.

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Figure 4: Total Dynamic Head

Calculations in Appendix 3: Total Dynamic Head Calculations show the calculated TDH for the cold fluid

is 3.44 ft. and hot is 4.223 ft. A TDH of 5 ft was selected for the pump in order to accommodate for both

TDHs of the fluids. This was figured by using a TDH approx. 20% greater than the needed for the hot

fluid. The hot fluid’s temperature was also an important factor in the pump decision. In order to

perform the desired experiment for our apparatus the water temperature needed to reach a maximum

of 180°F. This meant that the pump had to be able to withstand the hot liquid. Another factor was that

the pump had to work on 110 V. The pump and all the other components were restricted to working off

of 110 V because that was the power supply available in the school labs. From these criteria, and

keeping cost in mind, a pump was selected. The max flow rate of the selected pump equaled 13 GPM.

Once the total dynamic head of the system was calculated, it was possible to convert the value

from feet to psi by using the following formula:

P=0.434∗h∗SG

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Where “P” is the pressure in psi, “h” is the total dynamic head and “SG” is the specific gravity of

the fluid. In this case the specific gravity of water is 1.

P=0.434∗3.44∗1=1.49 psi

7.4. LabVIEW

LabVIEW is a development environment that engineers and scientists use for graphical

programming and hardware integration to design and deploy measurement and control systems.

LabVIEW is capable of: taking physical measurements, performing analysis and signal processing,

instrument control, displaying data on the user interface, logging data, and generating reports. It is

based on the graphical programming language G and is a higher-level language then C. When writing a

LabVIEW program the operator can focus on the task at hand, but in text-based programming the

operator is instead concerned about the code and syntax errors. A LabVIEW program is known as a VI,

which stands for virtual instrument. A VI consists of two major components. The first is a block diagram

where one can develop code. The operator can wire together graphical blocks to create a program. Each

block has inputs and outputs. When a block executes it produces data that flows down the wire to the

next block. The movement of the data determines the order of execution of the program. The second is

the user interface where one can customize objects like graphs, knobs, and buttons. Since LabVIEW is

similar to making a flow chart, it takes a fraction of the time to write a program compared to a text

based language. LabVIEW has been helping engineers since 1986. It is used in a wide variety of

industries such as: testing consumer electronics, controlling manufacturing machines autonomously,

and monitoring conditions in petroleum refineries.

LabVIEW is the software that one can install on their computer, but to begin acquiring data one

also needs hardware to integrate with the software. Team HELA began researching the different types of

hardware available. The main goal was to find a piece of hardware that met the following design criteria

for the project: monitor the flow rate of both hot and cool water streams, monitor temperature in four

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places on the heat exchanger, control the heat source, and be economically feasible. National

Instruments offers a wide variety of data acquisition (DAQ) hardware. With the project design criteria in

mind, Team HELA focused on a USB portable DAQ and a PC slot desktop DAQ. To be more specific, the

USB-6008 was compared against the PCIe-6320. To accommodate for the temperature sensors and two

flow rate sensors, the hardware needed to have a minimum of six analog inputs. The hardware also

needed a minimum of one analog output to control the heat source.

Table 1: Comparison of Hardware

Portable DAQUSB-6008

Desktop DAQPCIe-6320

• Easy USB connection• 8 inputs / 2 outputs• Sampling rate: 10kS/s• Input resolution: 12 bits• $169

• PC slot• 16 inputs / 0 outputs• Sampling rate: 250kS/s• Input resolution: 16 bits• $977

Whichever hardware included these primary needs, and was the least costly, was the one the team

would select. According to Table 1, USB-6008 meets all of the criteria.

7.5. Temperature Sensor

The project requires that a temperature measurement be taken at the four nozzles of the heat

exchanger. The temperature sensor that would be selected had to meet the following primary criteria:

take measurements of the water stream between room temperature and 200°F, take accurate

measurements, and be affordable. Team HELA did substantial research of various types of sensors that

included: thermocouple, RTD, thermistor, and fiber optic. It was narrowed down to a thermocouple and

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a RTD sensor. Thermocouples are the most popular temperature sensors, are effective in applications

that require a large temperature range, and are very inexpensive. A thermocouple is a junction of two

dissimilar metals that produce a temperature dependent voltage. For this reason, they are very rugged

and reliable. The LabVIEW hardware will measure the voltage the thermocouple produces and convert it

into a digital reading. RTD’s exploit the fact that the resistance of most metals increases with increasing

temperature and are simple in design. RTD’s are more accurate and stable then thermocouples, but are

also a little more expensive. In contrast to thermocouples, RTDs have a smaller temperature range,

require current excitation, and have slower response times. RTDs are primarily used for accurate

temperature measurements in applications that are not time critical. Table 2 shows a comparison of two

temperature sensors that fell into the projects criteria. The thermocouple was chosen because it is self-

powered, falls within the needed temperature range, and is least expensive.

Table 2: Comparison of Temperature Sensors

ThermocoupleTHMK-A01L10-01

RTDRTD1-D08L10-01

• Self-powered• Accuracy: ±1°F• 32-900°F• Response time: 2.9s• $26

• Stable readings• Accuracy:±0.27°F• -58-572°F• Response time: 7s• $43.50

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7.6. Heat Source

The project requires a heat source to increase the temperature of one of the water streams to

180°F. Team HELA researched different types of heat sources such as: an immersion heater, water

heater, and fish tank heater. An immersion heater would easily fit into one of the storage tanks, be very

inexpensive, and could be controlled by LabVIEW. A water heater would remove the need of a second

storage tank and control the temperature of the water with a built in controller, but is much more

expensive than an immersion heater. A fish tank heater is very similar to an immersion heater but does

not supply sufficient power to heat the water in a timely manner. The team is headed towards buying an

immersion heat source, but no decisions have been finalized. Another restriction imposed on our project

is the laboratory’s electrical system. The heat source would have to be able to run off of a normal 120V

electrical socket. Also, the heat source current draw needed to be below about 15A because that is the

normal current rating on an electrical outlet. The maximum wattage available from the electrical needed

to be calculated, and is shown below. Watts could be calculated by finding the product of the current,

power factor, and voltage. Once the maximum wattage was calculated, the minimum time required to

heat up 15 gallons of water was obtained. The equation needed to calculate the time required to heat

up the volume of water can be seen below.

P=I∗PF∗V

P=15 A∗1∗120V =1,800watts

P=(weight [lbs ]∗specific heat [ btu

lb· ° F]∗temperature change [° F ] )

(3.412 [ btuwatt·hr ]∗heat up time [hr ])

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1,800watts=[(15 gal∗8.3 lbs

gal )∗(1 btulb·° F )∗(180 ° F−75 ° F )]

(3.412 btuwatt·hr )∗(xhr )

time=2.13 hr

The results above state that the heat source had to run below the maximum 1,800 watts available to not

blow any circuit breakers. The 1,800 watts was plugged into the second equation and resulted in a time

of at least 2.13 hours to heat up the water. In the future when this experiment is performed, the TA

would have to heat the water a few hours in advance of the experiment.

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8. Design Objective

The project will consist of a Heat Exchanger Learning Apparatus that will have interchangeable

components and parameters that can be used by students in the Mechanical Engineering Technology

department at University of Houston. The apparatus can be used in classes such as Fluids Mechanics or

Elements of Plant Design. This product will allow students to obtain first-hand experience handling

important equipment such as a shell and tube heat exchanger and its components. Students will also be

able to collect experimental data for calculations of the heat transfer coefficient, log mean temperature

difference, number of tubes in the Head Exchanger, and some others variables that could be applied.

The apparatus will be supplied with specifications on how to setup the equipment in the lab, a

procedure on how to approach the lab and an example of typical experimental results that students may

obtain during the laboratory experience. This project consists of an innovating aspect. The

interchangeable bundles that will be incorporated into the design are not included in any of the

products currently offered. This aspect is going to enable students to get familiarized with the internal

components of shell and tube heat exchangers.

Some of the standards, regulations, and analysis that will be applied in the design process of the

Heat Exchanger Learning Apparatus are listed below.

The TEMA (Tubular Exchanger Manufacturers Association) standards

ASME Code Section VIII Division I

Thermal Calculations with the Aid of HTRI software

Pressure drop through the exchanger will be calculated and manually measured with

pressure gauges.

Incoming and outgoing temperature of the two fluids will be measured and calculated.

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Log mean temperature difference method will be used to manually calculate the

effectiveness of the exchanger.

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9. Design Procedure of Heat Exchanger

The design procedure of shell and tube heat exchangers has been deeply discussed throughout

the years. The procedure to successfully design a heat exchanger divides the process into the thermal

design and the mechanical design.

The very first step in the design process was to identify the problem. Once the problem was

recognized and all the parameters were set, the preliminary selection of the configuration was selected.

For Team HELA the main goal was to bridge the gap between theoretical knowledge and hands on

experience with heat exchangers at the University of Houston’s College of Technology. Based on

research and analysis, the TEMA type that best fit Team HELA’s application was the B E U configuration.

The heat exchanger would also have interchangeable bundles. The next step that was taken was to start

working on the thermal design of the heat exchanger. The team is currently in this step of the process

and is utilizing the HTRI software that aids engineers to run thermal calculations in heat exchangers.

Once the thermal design calculations were ready, and a specification sheet with the data was available,

the results were analyzed to see if the thermal performance or heat transfers meet the requirements set

by the team. Also, the pressure drop in the tube and shell sides needed to be in the applicable range

based on the pump that was selected. Once that step was completed, the group ran mechanical

calculations and made decisions based on the results to finalize the design. Figure 5 shows the flow

diagram that describes the process followed to design the heat exchanger.

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Figure 5 - Flow Diagram for heat exchanger design process

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10. Design Criteria

Based on the research and the calculations performed, the overall constraints for the HELA have

been gathered and established.

The Heat Exchanger designation according to TEMA standards will be a B-E-U exchanger that

consists of a removable channel and cover on the stationary head, a one-pass shell, and a U-tube bundle

in the rear side.

Shell and Tube Heat Exchanger Components:

O.D. of the Shell = 10 inch (standard pipe) Length = 35 inch Material = stainless steel

Bench:

Area = 5 ft2 (approx.) Height = 4 ft. (approx.)

Tanks:

Size = two 15 Gallons tanks

Other components:

4 temperature sensors 1 temperature controller 2 flow rate sensors LabVIEW software LabVIEW hardware Immersion heater 2 Centrifugal pumps

This is the basic design criteria that have been taken into account to design and run thermal and

mechanical calculations for the Heat Exchanger Learning Apparatus.

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10.1. Tube Layout Configuration

Team HELA selected the dimensions of the tubes for the three different bundle configurations

using ¾” standard tubes and ½” tubes. The selected configurations were: Case 1 having a configuration

with the maximum number of ¾” tubes possible for the shell size, Case 2 having almost the same

number of tubes but with a ½” diameter, and Case 3 having only seven ¾” inch tubes. These different

configurations were selected in order to give students a clear understanding on how the surface area

affects the heat transfer more than the number of tubes. All three cases are illustrated in Figures 6

through 8.

All three configurations used were U-bundles, and the number of tubes is equal to the number

of holes in the tube sheet. The number of tubes specified and calculated in the tube layout will be twice

the number of tubes. Another component that is seen in all three configurations is the use of two tie

rods. Tie rods are used to align the baffles properly within the bundle. Spacers are large diameter tubes

that are threaded over the tie rods and between the baffles to correct their spacing. The tie rods are

screwed into the tube sheet and run up to the support plate. The support plate is the last baffle located

at the quadrant of the bending tubes.

Figure 6 through 8 also contain some preliminary data including: shell diameter, number of

tubes, tube diameter, tube pitch, and tube layout angle.

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Figure 6 - HELA preliminary Case 1

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11. Thermal Analysis of the Heat Exchanger

One of the most common advantages that engineers have in industry is the use of software and

programs that allow them to input data, specifications of a project, and other input needed to be taken

into account for a particular project. The program performs the analysis based on standards, rules,

regulations, and codes to properly design an instrument or a piece of equipment based on standards or

regulations set by the client. For the thermal design analysis, Team HELA used software utilized by many

companies in the heat exchanger manufacturing industry. The software used, with Ohmstede Ltd license

and permission, for this project was HTRI.

HTRI (Heat Transfer Research Inc.) is a company that has been in the heat transfer industry for

more than 50 years. Their experience in heat transfer has helped them develop HTRI Xchanger Suite 6,

innovating software. This software helps engineers with the thermal design process of heat exchangers.

(HTRI)

HTRI is made up of different modules that can be used for different kinds of heat transfer

equipment. The module used by Team HELA is for the design of Shell and Tube Heat Exchangers. At the

same time, each module is divided into different modes. The Shell and Tube Heat Exchanger module is

divided into Rating, Simulation, and Design. Since the group already set constraints for the design, the

Simulation mode was selected. This mode allows the user to input various data, including the size of the

heat exchanger, to calculate the performance. It also outputs outlet temperatures, pressure drop,

Reynolds number in the heat exchanger, and other important parameters.

Using the simulation mode of HTRI to double check the calculations was very valuable for the

team. It also allowed the user to manipulate the parameters and try out new configurations. The group

was forced to understand the theory of the heat transfer formulas and physics being calculated by the

software. While working on the three different bundles Team HELA ran into some difficulties. For

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example, in one of the cases the software was warning that the B stream percentage was to low and

needed revision in order for the design to work. It was important to understand the different flow

fractions to optimize the heat transfer throughout the shell.

Figure 9 - Flow Streams

The B flow fraction penetrates the tubes the most out of all the fractions and transfers the most

heat between fluids. In order to optimize the design, flow stream fraction B had to have a significant

percentage of fluid. Manipulating the number of baffles in the shell, changing the tolerance between

the baffle and the inside diameter of the shell, and the outer tube limit dimension all affected the B flow

fraction dramatically. In the seven tube configuration a lot of the flow was falling into the flow stream

fraction C because the U-tubes don’t occupy much volume in the shell and therefore less resistance on

the shell fluid. A good solution for the problem was to add sealing strips that obligate the fluid to

penetrate the tube area and increase the B fraction percentage.

Another important factor that was taken into account while inputting the data into the HTRI

software product, was the fouling factor. “The fouling is a general term that includes any kind of deposit

of extraneous material that appears upon the heat transfer surface during the lifetime of the heat

exchanger. Whatever the cause or exact nature of the deposit, additional resistances to heat transfer is

introduced and the operational capability of the heat exchanges is correspondingly reduced.” (Thome)

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The fouling number used for each configuration was found in the TEMA standard, 0.002 ft2-hr-F/Btu.

This same number applies to the shell and the tube side as well.

11.1. Thermal Sample Calculations

In order to verify the values given by HTRI, Team HELA verified some of the parameters

calculated by the software. These parameters included:

Heat transfer rate

Exit water temperature of cold water

Log mean temperature difference (with correction factor)

Heat transfer area of bundle

Overall heat transfer coefficient

These values were calculated using parameters set as part of the design process, and where the same as

those entered into the HTRI software. Below are the equations used to calculate the values:

Equation 1: Heat transfer rate

Equation 2: Log mean temperature difference

Equation 3: Heat transfer area

Equation 4: Overall heat transfer coefficient

Using these equations we were able to verify the values obtained from HTRI for the heat exchanger

design with 52 bundle tubes. The calculations done can be found in Appendix 5: Thermal Calculations to

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Compare with HTRI Results. The table below shows the comparison of values calculated to values found

with HTRI software.

Calculated HTRI Software

% difference

Heat transfer rate (Btu/hr)

89268.322 88000 1.44

Exit water temperature of cold water (°F)

93.065 92.86 0.22

LTMD with factor (°F)

81.563 81.8 0.29

Heat transfer area of bundle (ft2)

17.112 17.111 0.01

Overall heat transfer coefficient (Btu/ft2*hr*°F)

63.958 63.36 0.94

Table 3: Comparison of values Calculated vs HTRI (52 tubes)

Comparing the values calculated with the ones produced from HTRI software gave percent differences of

less than 2%. In some values the percent difference was less than .3%. Performing this comparison gave

a better understanding of how the HTRI software worked.

HTRI outputs three pages of detailed final results, a graph for temperature differences, and also

the graph for Reynolds number in the shell and tube side that can be found in Appendix 4: HTRI Final

Results for all three cases. The TEMA specification sheet for each case is found in the following images

for a summary of the thermal results.

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11.2. Case 1 HTRI Results

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12. Mechanical Design of the Heat Exchanger

The type of body flanges on the inlet and outlet nozzles of the heat exchanger needed to be

chosen for the mechanical design. Based on economic constraints, Team HELA decided to use standard

ANSI flanges instead of designing custom-made forged flanges. The two main ANSI flanges considered

for the Heat Exchanger Learning Apparatus design were the weld neck and the slip-on type.

Figure 10 - Slip On and Weld Neck Flanges

Weld neck flange were designed to resist high temperatures and pressures. To be able to do so,

more material has to be incorporated in to the flange, especially in the hub. Weld neck flanges are

complex to manufacture making them one of the most expensive ANSI flanges. One advantage of this

type of flange configuration is that it only requires one weld to have it properly attached to the pipe. A

“V" bevel weld is required for this type of flange and in some cases requires two passes to completely fill

in the bevel area. On the other hand, the slip-on type flange requires two fillet welds to properly attach

the pipe and flange. Fillet welds are much easier to perform then “V” bevel welds. Some other benefits

of the slip-on flange were: the economical aspect, the shortness in height, requires less accuracy in

preparing the pipe it will be attached to, and good alignment since it slips over pipe. In addition to

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selecting the type of flanges for the heat exchanger, other components had to be chosen to start

running some mechanical calculations. The type of pipes for the shell and channel, the dimensions and

gauge of tubes, and the material of each were selected to initialize the calculations.

12.1. Mechanical Calculations:

Team HELA was assisted by two different software products to run mechanical calculations. The

first was RCS, which is used by one of our sponsors (Ohmstede LTD.) to run calculations and

simultaneously generate the solid model in SolidWorks. The other software was PVElite, this software

provided a detailed package of calculations using the most recent version of the ASME Code Section VIII

Division I. These regulations are used in industry for the design of pressure vessels. The calculations

attached in Appendix 6: Detail of Tube Sheet Calculations and Appendix 7: Flange Calculations provide

detailed information and outputs regarding the analysis of the heat exchanger. Team HELA decided to

manually calculate some of the most important mechanical aspects in the design in order to guarantee

that the results obtained by the software are accurate. The team also used it as a learning experience to

familiarize themselves with the use of the ASME code.

12.1.1. Shell Cylinder Calculations

Team HELA had to select a pipe that was compliant with ASME code for the use of the shell. The

formula for minimum thickness of shells under internal pressure given in section UG-27 was used to

calculate the minimum thickness required. The specifications of the pipe used for the design of the shell

have the following specifications:

Inside Diameter = 10 in

Element Thickness = 0.365 in

Design Pressure 10 psig (Calculated in the pump section of this report)

Material SA-312 TP304L

Allowable Stress, Operating = 14225 psi

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Material Density = 0.29 lbm/in3

The formula given in the ASME Code in section UG-27 to calculate minimum thickness for this case is:

t= PRSE−0.6 P

Where:

t=minimunrequired thicknessof shell

P = internal design pressure

R = inside radius of the shell course under consideration

S = maximum allowable stress value

E = Joint efficiency for approximate joint in cylindrical shells (In this case this value is 1 since the shell is a

seamless pipe)

t=(10∗5.135)

(14225∗1)−0.6(10)=0.00361∈¿

Comparing the results obtained of the thickness of the pipe with the required minimum

thickness shows that it was compliant with ASME code. Since the pipe was sufficiently thick, when the

group performed the calculations for the shell it passed the code regulations. The same formula was

used to calculate the minimum required thickness for the nozzles of the heat exchanger.

Another calculation that Team HELA decided to perform manually to compare with the results

obtained by the RCS software was the body flange design calculations. The section of the ASME Code

used to perform analysis of the body bolted flange connections with ring type gaskets was in the

Appendix 2 of the ASME code.

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12.1.2. Tube sheet Calculations

The results for the tube sheet calculations following the ASME Code UHX-12 are given step by

step in the format obtained from RCS. The calculations are run in six different cases that are summarized

at the end of the report and give the required thickness of the tube sheet and the actual thickness. The

minimum thickness required by the code for the tube sheet was selected.

U-Tube Tubesheet results per ASME UHX-12 2010, 2011a

Results for 6 Load Cases:

--Reqd. Thk. + CA -------- Tubesheet Stresses Case Pass/

Case# Tbsht Extnsn Bend Allwd Shear Allwd Type Fail

----------------------------------------------------------------------------

1uc 1.250 ... 665 28450 47 11380 Fvs+Pt Ok

2uc 1.250 ... 665 28450 47 11380 Ps+Fvt Ok

3uc 0.020 ... ... 28450 ... 11380 Ps+Pt Ok

1c 0.473 ... 837 28450 59 11380 Fvs+Pt-Ca Ok

2c 0.473 ... 837 28450 59 11380 Ps+Fvt-Ca Ok

3c 0.270 ... ... 28450 ... 11380 Ps+Pt-Ca Ok

----------------------------------------------------------------------------

Max: 1.2500 ... in 0.029 0.005 (Str. Ratio)

Load Case Definitions:

Fvs,Fvt - User-defined Shell-side and Tube-side vacuum pressures or 0.0.

Ps, Pt - Shell-side and Tube-side Design Pressures.

Ca - With or Without Corrosion Allowance.

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Summary of Thickness Comparisons for 6 Load Cases:

----------------------------------------------------------------------------

Thickness (in) Required Actual P/F

----------------------------------------------------------------------------

Tubesheet Thickness : 1.2500 1.2500 Ok

Tube Thickness : 0.0060 0.1094 Ok

----------------------------------------------------------------------------

12.1.3. Flange Calculations

The body flanges selected for the heat exchanger are ANSI standard slip on flanges with a 10”

nominal pipe size. In order to confirm that the selected rating of 150 lb flange was going to pass the

calculations from the ASME Code standards, a complete analysis was run using the PV Elite software.

The gasket selection was an important factor in the calculations. Based on the results, the group

selected Gore Tex gasket with a thickness of .010” and a standard nominal width of ½”. A beneficial

aspect of this gasket is that it comes in a tape form, which can be reused and ease to install. The flange

calculations package as well as the input data for the two body flanges of the heat exchanger can be

found in Appendix 7: Flange Calculations of this report.

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13. Gantt Chart:

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14. Cost Estimation:

The cost estimation was made based on research and quotes from several companies to forecast the cost of the materials needed in the

design of the project. All prices are subject to change with deeper investigation for better prices and special discounts as students. The table with

the list of equipment, prices, and sources is shown below.

Equipment Qty. Unit Price Total

Shell and Tube Heat Exchanger with 3 Bundles 1 $1,500.00 $1,500.00Tanks 2 $270.00 $540.00Temperature Sensors 4 $26.00 $104.00Flow Rate Sensors 2 $350.00 $700.00Immersion Heater 1 $20.00 $20.00Centrifugal Pumps 2 $104.00 $208.00Bench 1 $190.00 $190.00Miscellaneous N/A $600.00 $600.00Computer, Software, Hardware 1 $600.00 $600.00Estimated Total $4,462.00

The total value was adjusted adding $600.00 for miscellaneous parts which includes the piping, bolts, gaskets, and other components that may

be needed to assemble the system.

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Works CitedCengel, Yunus. Heat and Mass Transfer A Practical Approach, Third Edition. New York: McGraw Hil Companies, Inc.l ,

2007.

Energy, U.S. Department of. "DOE FUNDAMENTALS HANDBOOK MECHANICAL SCIENCE." Washington, 1993. Vol. 1.

Engineers, 17-2141 Mechanical. U.S. Bureau of Labor Statistics. n.d. 06 February 2013.

Engineers, Mechanical. Government of Canada, Service Canada, Quebec, Programs Agreements and Partnership. 06 February 2013.

Groups, Engineering. Mechanical Engineering Job Growth. n.d. 06 February 2013.

HTRI. Heat Transfer Research Inc. n.d. <http://www.htri.net/articles/htri_xchanger_suite>.

Insight, Jobs Trends. Hiring Demand for Mechanical Engineers Nears 4-Year. n.d. 06 February 2013.

Kakac, S. "Heat Exchangers: Selection, Rating, and Thermal Design." Liu., Hongtan. Boca Raton, FL: CRC, 2002.

Kakac, Sadik. Heat Exchangers Selection, Rating, and Thermal Design. Miami: CRC PRESS, 2002.

Market, Mechanical Engineer: Duties & Job. Mechanical Engineer Job Description & Market Demand. n.d. 06 February 2013.

Robert H. Perry, Don W. Green. Perry's Chemical Engineers' Handbook, Eight Edition. New York: McGraw-Hill, 2008.

TEMA. Tubular Exchanger Manufacturers Association Inc. n.d. <http://www.tema.org/>.

Thome, John R. Wolverine Tube Heat Transfer Data Book. Wolverine Tube, Inc., 2010.

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Appendix 1: Quote from American Eagle Oilfield

Inquiry for Apparatus Model # HE 158C- Offer from American eagle Oilfield Services & Supplies, Inc.

TO: University Of Houston Houston, TEXAS Tel: 409 457 3499 Attn. Mr. Robert Maduro Academic Support Asst. Reference to the above mentioned subject, and on behalf of our principles {Solution Engineering SDN.BHD "SOLTEQ" },Please find enclosed / attached our OFFER for the following items: Item Qty Descriptions U/Price Extended----- ------ ------------------------------------- ---------- ---------------1 1 pc Heat exchanger training Apparatus. 22,750.00 22,750.00 Model # HE158C OPTIONAL ITEMS: 1 pc EI-DIGITAL INSTRUMINATIONS 2,442.00 2,442.00 1 pc DAS-DATA ACQUISITION SYSTEMS 3,406.00 3,406.00 1 pc PC-DESKTOP PC 1,041.00 1,041.00 ------------- Total Prices FOB Port Klang - Malaysia: US $ 29,639.00==================================================================TERMS & CONDITIONS=================- Manufacturer: SOLTEQ - Malaysia.- Technical Data sheets attached.- Warranty: 18 Months after the shipment date.- Delivery: 3-4 Months (ex-Factory). Delivery depends on when order/payment received.- Prices: FOB Port Klang-Malaysia (Excluded Insurance coverage).- Payment Terms: 50% Down Payment With the order. 50% Due Which shipment is ready for dispatched. Should you need any further assistant, please feel free to contact the undersigned. Looking forward to receiving your valuable order. Thank you,Tahsien KallaPresdent/CEOAmerican Eagle Oilfield Services & Supplies, Inc.1840 Snake River Road, Suite CKaty, Texas 77449Tel : 281 829 3838

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Appendix 2: Echoscan LLC Quotation

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Appendix 3: Total Dynamic Head Calculations

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Appendix 4: HTRI Final Results

Case 1

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Case 2

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Case 3

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Appendix 5: Thermal Calculations to Compare with HTRI Results

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Appendix 6: Detail of Tube Sheet Calculations

UHX-12.5.1 Step 1:

Compute the Equivalent Outer Tube Limit Circle Diameter [Do]:

= 2 * ro + dt

= 2 * 4.3077 + 0.7500 = 9.365 in

Determine the Basic Ligament Efficiency for Shear [mu]:

= (p - dt) / p

= (1.250 - 0.750 ) / 1.250 = 0.400

UHX-12.5.2 Step 2 :

Compute the Ratio [Rhos]:

= Gs / Do (Configurations d, e, f)

= 12.5000 / 9.3654 = 1.3347

Compute the Ratio [Rhoc]:

= Gc / Do (Configurations d)

= 12.5000 / 9.3654 = 1.3347

Moment on Tubesheet due to Pressures (Ps, Pt) [Mts]:

= Do²/16 * [(Rhos-1)*(Rhos²+1)* Ps - (Rhoc-1) * (Rhoc²+1) * Pt ]

= 9.365²/16 * [ (1.335 - 1) * (1.335² + 1) * 10.000 -

(1.335 - 1) * (1.335² + 1) * 0.000 ]

= 51.0335 psig*in²

UHX-12.5.3 Step 3, Determination of Effective Elastic Properties :

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Compute the Ratio [rho]:

= ltx / h = 1.1250 / 1.0000 = 1.0000 ( must be 0 <= rho <= 1 )

Compute the Effective Tube Hole Diameter [d*]:

= max( dt - 2tt*( Et/E )( St/S )( rho ), dt - 2tt)

= max( 0.7500 -2*0.1094 *(27475000 /27475000 )*

( 14225 /14225 )*(1.000 ), 0.7500 -2*0.1094 )

= 0.5312 in

Compute the Effective Tube Pitch [p*]:

= p / sqrt( 1 - 4 * min( AL * CNV_factor, 4*Do*p)/(Pi * Do²) )

= 1.2500 / sqrt( 1 - 4 * min( 19.38 *1.000 , 4*9.365 *1.250 )

(3.141* 9.365²) )

= 1.4746 in

Compute the Effective Ligament Efficiency for Bending [mu*]:

= (p* - d*) / p* = (1.4746 - 0.5312 ) / 1.4746 = 0.63976

Note: mu* is > 0.6, Div. 1 Part UHX data for E*/E and nu* are not applicable.

Data from Div. 2 App. 5.E is used.

E*/E, nu* for Triangular pattern from Div. 2 Tables 5.E.1, 5.E.2.

h/p = 0.800000 ; mu* = 0.639759

E*/E = 0.748851 ; nu* = 0.292479 ; E* = 20574688. psi

Skip Step 4 for Configuration d :

UHX-12.5.5 Step 5:

Diameter ratio [K]:

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= A / Do = 12.7500 / 9.3654 = 1.3614

Determine Coefficient [F]:

= (1 - nu*)/E* * ( E * ln(K) )

= (1 - 0.29 )/20574688 * ( 27475000 * ln(1.36 ) )

= 0.2915

UHX-12.5.6 Step 6:

Moment Acting on Unperforated Tubesheet Rim [M*]

= Mts + W* * (Gc - Gs)/(2 * pi * Do)

= 51.0 + 1227.2 * (12.500 - 12.500 )/(2 * pi * 9.365 )

= 51.0335 psig*in²

UHX-12.5.7 Step 7:

Maximum Bending Moment acting on Periphery of Tubesheet [Mp]:

= ((M*) - Do²/32 * F * (Ps - Pt) ) / (1 + F)

= ((51.03 ) - 9.365²/32 * 0.291 * (10.00 - 0.00 ) ) / (1 + 0.29 )

= 33.3293 psig*in²

Maximum Bending Moment acting on Center of Tubesheet [Mo]:

= Mp + Do²/64 * (3 + rnu*)(Ps - Pt)

= 33.33 + 9.365²/64 * (3 + 0.292 )(10.00 - 0.00 )

= 78.4520 psig*in²

Maximum Bending Moment acting on Tubesheet [M]:

= Max( |Mp|, |Mo| )

= Max( |33.329 |, |78.452 | )

= 78.4520 psig*in²

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UHX-12.5.8 Results for Step 8:

Tubesheet Bending Stress at Original Thickness:

= 6 * M / ( (mu*) * ( h - hg')² )

= 6 * 78.452 / ( (0.6398 ) * ( 1.0000 - 0.0625 )² )

= 837.1373 psi

The Allowable Tubesheet Bending Stress [SigmaAll]:

= 2 * S = 2 * 14225.00 = 28450.00 psi

Tubesheet Bending Stress at Final Thickness [Sigma]:

= 6 * M / ( (mu*) * ( h - hg')²

= 6 * 78.293 / ( (0.6398 ) * ( 0.2232 - 0.0625 )²

= 28419.2910 psi

Required Tubesheet Thickness, for Bending Stress [HreqB]:

= H + CATS + CATC = 0.2232 + 0.1250 + 0.1250 = 0.4732 in

Required Tubesheet Thickness for Given Loadings (includes CA) [Hreq]:

= Max( HreqB, HreqS ) = Max( 0.4732 , 0.2551 ) = 0.4732 in

UHX-12.5.9 Step 9:

|Ps - Pt| = |10.00 - 0.00 | = 10.000 psig

Shear Stress check [Tau_limit]:

= 3.2 * S * MU * h / Do

= 3.2 * 14225.00 * 0.400 * 1.000 / 9.37 = 1944.18 psig

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Average Shear Stress at the Outer Edge of Perforated Region [Tau]:

= 1/(4* Mu) * (Do/h) * |Ps - Pt|

= 1/(4*0.400)*(9.37/1.00)*|10.00-0.00|psi

= 58.53 psi

Note: Analysis Completed for Tubesheet Configuration d.

Stress/Force summary for loadcase 2 corr. (Ps + Fvt):

------------------------------------------------------------------------

Stress Description Actual Allowable Pass/Fail

------------------------------------------------------------------------

Tubesheet bend. stress 837.1 <= 28450.0 psi Ok

Tubesheet shear stress 58.5 <= 11380.0 psi Ok

------------------------------------------------------------------------

Thickness results for loadcase 2 corr. (Ps + Fvt):

----------------------------------------------------------------------------

Thickness (in) Required Actual P/F

----------------------------------------------------------------------------

Tubesheet Thickness : 0.4732 1.2500 Ok

----------------------------------------------------------------------------

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Appendix 7: Flange Calculations

Flange Input Data Values Description: Channel to TubeSheet :

Channel to Tubesheet Flg

Description of Flange Geometry (Type) Integral Slip On

Design Pressure P 10.00 psig

Design Temperature 205 °F

Internal Corrosion Allowance ci 0.1250 in

External Corrosion Allowance ce 0.0000 in

Use Corrosion Allowance in Thickness Calcs. No

Flange Inside Diameter B 10.020 in

Flange Outside Diameter A 16.000 in

Flange Thickness t 1.1900 in

Thickness of Hub at Small End go 0.8329 in

Thickness of Hub at Large End g1 0.9250 in

Length of Hub h 0.7500 in

Flange Material SA-182 F304L

Flange Material UNS number S30403

Flange Allowable Stress At Temperature Sfo 14225.00 psi

Flange Allowable Stress At Ambient Sfa 16700.00 psi

Bolt Material SA-193 B8

Bolt Allowable Stress At Temperature Sb 16700.00 psi

Bolt Allowable Stress At Ambient Sa 18800.00 psi

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Diameter of Bolt Circle C 14.250 in

Nominal Bolt Diameter a 0.8750 in

Type of Threads TEMA Thread Series

Number of Bolts 12

Flange Face Outside Diameter Fod 12.750 in

Flange Face Inside Diameter Fid 10.750 in

Flange Facing Sketch 1, Code Sketch 1a

Gasket Outside Diameter Go 11.750 in

Gasket Inside Diameter Gi 10.750 in

Gasket Factor m 2.0000

Gasket Design Seating Stress y 2800.00 psi

Column for Gasket Seating 2, Code Column II

Gasket Thickness tg 0.0100 in

ANSI Flange Class 150

ANSI Flange Grade GR 2.2

ASME Code, Section VIII, Division 1, 2010, 2011a

Corroded Flange ID, Bcor = B+2*Fcor 10.270 in

Corroded Large Hub, g1Cor = g1-ci 0.800 in

Corroded Small Hub, g0Cor = go-ci 0.708 in

Code R Dimension, R = ((C-Bcor)/2)-g1cor 1.190 in

Gasket Contact Width, N = (Go - Gi) / 2 0.500 in

Basic Gasket Width, bo = N / 2 0.250 in

Effective Gasket Width, b = bo 0.250 in

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Gasket Reaction Diameter, G = (Go + Gi) / 2 11.250 in

Basic Flange and Bolt Loads:

Hydrostatic End Load due to Pressure [H]:

= 0.785 * G² * Peq

= 0.785 * 11.2500² * 10.000

= 994.020 lbf

Contact Load on Gasket Surfaces [Hp]:

= 2 * b * Pi * G * m * P

= 2 * 0.2500 * 3.1416 * 11.2500 * 2.0000 * 10.00

= 353.429 lbf

Hydrostatic End Load at Flange ID [Hd]:

= Pi * Bcor² * P / 4

= 3.1416 * 10.2700² *10.0000/4

= 828.382 lbf

Pressure Force on Flange Face [Ht]:

= H - Hd

= 994 - 828

= 165.637 lbf

Operating Bolt Load [Wm1]:

= max( H + Hp + H'p, 0 )

= max( 994 + 353 + 0 , 0 )

= 1347.449 lbf

Gasket Seating Bolt Load [Wm2]:

= y * b * Pi * G + yPart * bPart * lp

= 2800.00*0.2500*3.141*11.250+0.00*0.0000*0.00

= 24740.043 lbf

Required Bolt Area [Am]:

= Maximum of Wm1/Sb, Wm2/Sa

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= Maximum of 1347/16700 , 24740/18800

= 1.316 in²

ASME Maximum Circumferential Spacing between Bolts per App. 2 eq. (3) [Bsmax]:

= 2a + 6t/(m + 0.5)

= 2 * 0.875 + 6 * 1.190/(2.00 + 0.5)

= 4.606 in

Actual Circumferential Bolt Spacing [Bs]:

= C * sin( pi / n )

= 14.250 * sin( 3.142/12 )

= 3.688 in

ASME Moment Multiplier for Bolt Spacing per App. 2 eq. (7) [Bsc]:

= max( sqrt( Bs/( 2a + t )), 1 )

= max( sqrt( 3.688/( 2 * 0.875 + 1.190 )), 1 )

= 1.1200

Bolting Information for TEMA Imperial Thread Series (Non Mandatory):

-----------------------------------------------------------------------------

Minimum Actual Maximum

-----------------------------------------------------------------------------

Bolt Area, in² 1.316 5.028

Radial distance bet. hub and bolts 1.250 1.190

Radial distance bet. bolts and the edge 0.938 0.875

Circumferential spacing between bolts 2.063 3.688 4.606

-----------------------------------------------------------------------------

Min. Gasket Contact Width (Brownell Young) [Not an ASME Calc] [Nmin]:

= Ab * Sa/( y * Pi * (Go + Gi) )

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= 5.028 * 18800.00/(2800.00 * 3.14 * (11.750 + 10.75 ) )

= 0.478 in

Flange Design Bolt Load, Gasket Seating [W]:

= Sa * ( Am + Ab ) / 2

= 18800.00 * ( 1.3160 + 5.0280 )/2

= 59633.22 lbf

Gasket Load for the Operating Condition [HG]:

= Wm1 - H

= 1347 - 994

= 353.43 lbf

Moment Arm Calculations:

Distance to Gasket Load Reaction [hg]:

= (C - G ) / 2

= ( 14.2500 - 11.2500 )/2

= 1.5000 in

Distance to Face Pressure Reaction [ht]:

= ( R + g1 + hg ) / 2

= ( 1.1900 + 0.8000 + 1.5000 )/2

= 1.7450 in

Distance to End Pressure Reaction [hd]:

= R + ( g1 / 2 )

= 1.1900 + ( 0.8000/2.0 )

= 1.5900 in

Summary of Moments for Internal Pressure:

Loading Force Distance Bolt Corr Moment

End Pressure, Md 828. 1.5900 1.1200 1475. in-lb

Face Pressure, Mt 166. 1.7450 1.1200 324. in-lb

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Gasket Load, Mg 353. 1.5000 1.1200 594. in-lb

Gasket Seating, Matm 59633. 1.5000 1.1200 100187. in-lb

Total Moment for Operation, Mop 2393. in-lb

Total Moment for Gasket seating, Matm 100187. in-lb

Note: User choose not to perform Stress Calculations on this ANSI Flange.

Pressure rating of the flange will be used to check code compliance.

Estimated Finished Weight of Flange at given Thk. 48.7 lbm

Estimated Unfinished Weight of Forging at given Thk 68.8 lbm

PV Elite is a trademark of Intergraph CADWorx & Analysis Solutions, Inc. 2013

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Flange Input Data Values Description: TubeSheet to Shell :

Tubesheet to Shell Flg

Description of Flange Geometry (Type) Integral Slip On

Design Pressure P 10.00 psig

Design Temperature 205 °F

Internal Corrosion Allowance ci 0.1250 in

External Corrosion Allowance ce 0.0000 in

Use Corrosion Allowance in Thickness Calcs. No

Flange Inside Diameter B 10.020 in

Flange Outside Diameter A 16.000 in

Flange Thickness t 1.1900 in

Thickness of Hub at Small End go 0.8329 in

Thickness of Hub at Large End g1 0.9250 in

Length of Hub h 0.7500 in

Flange Material SA-182 F304L

Flange Material UNS number S30403

Flange Allowable Stress At Temperature Sfo 14225.00 psi

Flange Allowable Stress At Ambient Sfa 16700.00 psi

Bolt Material SA-193 B8

Bolt Allowable Stress At Temperature Sb 16700.00 psi

Bolt Allowable Stress At Ambient Sa 18800.00 psi

Diameter of Bolt Circle C 14.250 in

Nominal Bolt Diameter a 0.8750 in

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Type of Threads TEMA Thread Series

Number of Bolts 12

Flange Face Outside Diameter Fod 12.750 in

Flange Face Inside Diameter Fid 10.750 in

Flange Facing Sketch 1, Code Sketch 1a

Gasket Outside Diameter Go 11.750 in

Gasket Inside Diameter Gi 10.750 in

Gasket Factor m 2.0000

Gasket Design Seating Stress y 2800.00 psi

Column for Gasket Seating 2, Code Column II

Gasket Thickness tg 0.0100 in

ANSI Flange Class 150

ANSI Flange Grade GR 2.2

ASME Code, Section VIII, Division 1, 2010, 2011a

Corroded Flange ID, Bcor = B+2*Fcor 10.270 in

Corroded Large Hub, g1Cor = g1-ci 0.800 in

Corroded Small Hub, g0Cor = go-ci 0.708 in

Code R Dimension, R = ((C-Bcor)/2)-g1cor 1.190 in

Gasket Contact Width, N = (Go - Gi) / 2 0.500 in

Basic Gasket Width, bo = N / 2 0.250 in

Effective Gasket Width, b = bo 0.250 in

Gasket Reaction Diameter, G = (Go + Gi) / 2 11.250 in

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Basic Flange and Bolt Loads:

Hydrostatic End Load due to Pressure [H]:

= 0.785 * G² * Peq

= 0.785 * 11.2500² * 10.000

= 994.020 lbf

Contact Load on Gasket Surfaces [Hp]:

= 2 * b * Pi * G * m * P

= 2 * 0.2500 * 3.1416 * 11.2500 * 2.0000 * 10.00

= 353.429 lbf

Hydrostatic End Load at Flange ID [Hd]:

= Pi * Bcor² * P / 4

= 3.1416 * 10.2700² *10.0000/4

= 828.382 lbf

Pressure Force on Flange Face [Ht]:

= H - Hd

= 994 - 828

= 165.637 lbf

Operating Bolt Load [Wm1]:

= max( H + Hp + H'p, 0 )

= max( 994 + 353 + 0 , 0 )

= 1347.449 lbf

Gasket Seating Bolt Load [Wm2]:

= y * b * Pi * G + yPart * bPart * lp

= 2800.00*0.2500*3.141*11.250+0.00*0.0000*0.00

= 24740.043 lbf

Required Bolt Area [Am]:

= Maximum of Wm1/Sb, Wm2/Sa

= Maximum of 1347/16700 , 24740/18800

= 1.316 in²

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ASME Maximum Circumferential Spacing between Bolts per App. 2 eq. (3) [Bsmax]:

= 2a + 6t/(m + 0.5)

= 2 * 0.875 + 6 * 1.190/(2.00 + 0.5)

= 4.606 in

Actual Circumferential Bolt Spacing [Bs]:

= C * sin( pi / n )

= 14.250 * sin( 3.142/12 )

= 3.688 in

ASME Moment Multiplier for Bolt Spacing per App. 2 eq. (7) [Bsc]:

= max( sqrt( Bs/( 2a + t )), 1 )

= max( sqrt( 3.688/( 2 * 0.875 + 1.190 )), 1 )

= 1.1200

Bolting Information for TEMA Imperial Thread Series (Non Mandatory):

-----------------------------------------------------------------------------

Minimum Actual Maximum

-----------------------------------------------------------------------------

Bolt Area, in² 1.316 5.028

Radial distance bet. hub and bolts 1.250 1.190

Radial distance bet. bolts and the edge 0.938 0.875

Circumferential spacing between bolts 2.063 3.688 4.606

-----------------------------------------------------------------------------

Min. Gasket Contact Width (Brownell Young) [Not an ASME Calc] [Nmin]:

= Ab * Sa/( y * Pi * (Go + Gi) )

= 5.028 * 18800.00/(2800.00 * 3.14 * (11.750 + 10.75 ) )

= 0.478 in

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Flange Design Bolt Load, Gasket Seating [W]:

= Sa * ( Am + Ab ) / 2

= 18800.00 * ( 1.3160 + 5.0280 )/2

= 59633.22 lbf

Gasket Load for the Operating Condition [HG]:

= Wm1 - H

= 1347 - 994

= 353.43 lbf

Moment Arm Calculations:

Distance to Gasket Load Reaction [hg]:

= (C - G ) / 2

= ( 14.2500 - 11.2500 )/2

= 1.5000 in

Distance to Face Pressure Reaction [ht]:

= ( R + g1 + hg ) / 2

= ( 1.1900 + 0.8000 + 1.5000 )/2

= 1.7450 in

Distance to End Pressure Reaction [hd]:

= R + ( g1 / 2 )

= 1.1900 + ( 0.8000/2.0 )

= 1.5900 in

Summary of Moments for Internal Pressure:

Loading Force Distance Bolt Corr Moment

End Pressure, Md 828. 1.5900 1.1200 1475. in-lb

Face Pressure, Mt 166. 1.7450 1.1200 324. in-lb

Gasket Load, Mg 353. 1.5000 1.1200 594. in-lb

Gasket Seating, Matm 59633. 1.5000 1.1200 100187. in-lb

84 | P a g e

Total Moment for Operation, Mop 2393. in-lb

Total Moment for Gasket seating, Matm 100187. in-lb

Note: User choose not to perform Stress Calculations on this ANSI Flange.

Pressure rating of the flange will be used to check code compliance.

Estimated Finished Weight of Flange at given Thk. 48.7 lbm

Estimated Unfinished Weight of Forging at given Thk 68.8 lbm

PV Elite is a trademark of Intergraph CADWorx & Analysis Solutions, Inc. 2013

85 | P a g e

Appendix 8: Heat Exchanger Drawings

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Appendix 9: Total Working Hours for the Project

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Date post:	01-Feb-2016
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