You are on page 1of 36

Effects of Temperature Change on Pressure

Testing and Maintaining Environmental

Compliance

Arthur D. Bosshart II

TECO Energy

07/09/08

Arthur D Bosshart II
TECO Energy

Table of Contents
Abstract ….………………………………………………………………………….. 3

Introduction …………………………………………………………………………. 3

Field Tests and Analysis …………………………………….…………………….. 4

Proposed Procedure ………………………………………….……………………. 9

Ideal Testing Conditions ……………………………………….………………….. 11

Conclusions ……………………………………………………….………………… 13

Acknowledgments ………………………………………………………………….. 14

Bibliography ………………………………………………………………………… 15

Appendix …………………………………………………………………………….. 16
A) Calculations ……………………………………………………………………………… 16
B) Example spread sheet walkthrough ……………………………………………...…… 18
C) Assumptions ……………………………………………………………………………... 21
D) Nomenclature ……………………………………………...……………….….………… 21
E) Simplified Field Method …………..……………………...….…………….….………… 22
F) APT Lookup Table …...…………………………………...……………….….………… 24
G) Compliance Curve …………..……..………….……...….……………….….………… 25
H) Simplified Field Method Sample Calculation ……………...………….….………… I) 25
Field Pressure Testing Packet …...…………………………...………….….………… J) 27
Completed Line Pressure Test Worksheet ……………...………….….………...…… K) 33
Calculation of the “P” Coefficient …...…………………………...……….….………… L) 34
Calculation of a Specific APT Value ……………...………….….…………...…...…… 36

Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 2

Arthur D Bosshart II
TECO Energy

Abstract

The API 1110 pressure test method is used for determining leaks within piping segments in

contact with soil or above water. A criticism of this current method is that it does not account for

temperature effects on the contained substance in the piping. These temperature variances

affect the measured pressure during a test and depending on testing conditions can pass a failed

test or fail a passed test. The proposed alternate method and associated calculations account for

a temperature change that can occur during a pressure test and correlates an unaccounted

volume of substance to the Table BPP located in Rule 62-762.601, Florida Administrative Code

(F.A.C.) to determine pass or fail.

Introduction

The purpose of this paper is to define the allowable pressure tolerances of the API 1110

pressure test method between the theoretical pressure change and the actual pressure change

associated with a temperature change of a contained substance within piping during a pressure

test. A volumetric difference, over a testing duration, can be associated with the difference

between the theoretically calculated and actual measured pressures and then correlated to the

Table BPP found in Rule 62-762.601, F.A.C. to identify a passed or failed test in accordance with

API 1110 pressure test method. Ideal testing conditions will then be identified to ensure accuracy

and confidence in a given pressure test. There are a number of influences that affect the final

results of pressure tests such as the change in substance temperature within the piping, ambient

temperature changes, piping temperature change, piping material, substance within the pipe,

thermal expansion rates, compressibility, percentage of pipe directly in contact with sunlight, and

volume of piping isolated for testing. Some of the factors noted above have a greater effect than

others.

The most important operational condition to monitor, other than pressure, is the

temperature of the substance within the pipe. Depending upon the type of substance, a change

in temperature can have dramatic results. Using #2 diesel fuel as an example, if a temperature
o
change of 1 F occurs within an isolated volume, the pressure will increase or decrease by 70 psi

Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 3

Without monitoring the temperature of the substance within the pipe. The magnitude of the increase is determined by the solar radiation intensity and if the pipe is coated with an energy absorbing color like black then a greater temperature change will occur. final ambient temperature. Given that the piping section being tested is isolated. The pressure will vary depending on the volumetric thermal expansion rate of #2 diesel fuel and the piping material. This is a potential deficiency of this test. Another important factor to account for is the energy transfer between the outside environment and the pipe and between the pipe and the substance contained therein. initial interior pipe surface temperature and final interior pipe surface temperature. and energy transfers between materials. These relationships are described in Fourier's law. initial exterior pipe surface temperature. pressure changes. Fourier's law describes linear heat flow rate between two surfaces. The temperature change is determined by the thermal conductivity of the piping material. Arthur D Bosshart II TECO Energy to 100 psi. two examples of API 1110 pressure tests that were recently conducted in the field at TECO Energy facilities will be examined to illustrate the temperature changes. This is because liquids are not easily compressible like gases. pressure fluctuations cannot be accounted for other than reasoning that a product loss had occurred meaning that there is a leak in the pipe that was pressure tested. energy transfer is the reason why a substance’s temperature will increase during a test. Currently. schedule of the piping. there will be a substantial delay between the ambient or environmental temperature change and the temperature change of the substance. there is no protocol in the current API 1110 pressure test method that requires that the liquid temperature be monitored throughout the duration of a test. If the heat capacity of the contained substance and thermal conductivity of the substance’s surroundings are accounted for. This reasoning is not accurate. the heat capacity of the liquid. final exterior pipe surface temperature. Field Tests and Analysis For purposes of this paper. initial ambient temperature. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 4 . the energy flux. If a portion of the piping is exposed to the sun the exterior surface temperature of the piping will increase.

2007 located in Apollo Beach.m. to 3:19 p. Arthur D Bosshart II TECO Energy Example #1: This API 1110 pressure test was conducted at the TECO Big Bend Plant on February 12. FL from 2:00 p. The test was performed on a Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 5 .m.

and the heat capacity of the #2 diesel. The #2 diesel fuel did not reach a thermal steady state with the pipe’s exterior surface because of the length of the test. it is important to note the pressure increase and the temperature increase. the temperature of the #2 diesel fuel only increased by o o 1. Although the ambient o temperature was only around 70 F.285 F. Readings were recorded every 15 minutes throughout the testing duration and before depressurization. This temperature difference is attributed to the energy absorbing ability of the pipe’s exterior coating and the solar radiation directly incident upon the pipe. When using Fourier's law to describe the heat transfer occurring within this test. and the heat capacity of the contained liquid. respectively. The initial pressure and temperature readings were o recorded at 107psi and 65 F. and into an aboveground storage tank system. Arthur D Bosshart II TECO Energy section of piping nearly 900 feet in length constructed of carbon steel. Although the o ambient temperature increased by 5 F. the temperature of the piping exterior surface. along the side of the canal. one needs to look at the piping schedule. This 1. over a canal. radiation diffused through the surrounding environment. The weather conditions during this test were partly cloudy with a light breeze. This portion of piping is entirely aboveground and transports fuel from a pump house. Contained within the pipe is #2 diesel fuel. and radiation reflected upon the pipe’s surface from the water below. the temperature of the pipe’s exterior surface was most likely o o around the range of 80 F to 85 F. the rate at which heat is conducted through the carbon steel piping. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 6 . The temperature recordings were of the ambient environmental temperature. When analyzing the data associated with Example #1. the energy transfer through the pipe. the final reading was recorded at 234psi and o 70 F.285 F temperature rise occurred mainly due to solar radiation incident upon the pipe’s exterior surface. The change in ambient temperature appears to have had a smaller impact.

FL from 3:20 p.m. to 4:40 p. Arthur D Bosshart II TECO Energy Example #2 This API 1110 pressure test was conducted at the TECO Big Bend Plant on February 12. The test was performed on a Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 7 . 2007 located in Apollo Beach.m.

This occurs because underground temperature remains relatively stable throughout the day because the ground acts as an insulator and limits the impact of the ambient temperature fluctuation. heat flow will still occur from the ground surface to the soil in contact with the pipe. The weather conditions during this test were partly cloudy. During the time these last readings were taken. Temperature under the soil surface remains stable because heat transfer occurs through multiple layers with varying thermal conductivities. Although the ground acts as an insulator. both tests passed because neither fell substantially below the initial pressure Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 8 .15 F change occurred to cause a 14. The initial pressure and temperature readings were o recorded at 160psi and 72 F. from the soil in contact with the pipe to the pipe’s exterior surface. Note that only a o 0. heat is flowing in the opposite direction from the warmer liquid to the cooler interior surface of the pipe. When looking at the first four readings of the test it is important to note that the temperature decreases and the pressure increases. The temperature recordings were of the ambient environmental temperature. Readings were recorded every 15 minutes throughout the testing duration and before depressurization. If there is no substantial pressure drop. Arthur D Bosshart II TECO Energy section of piping between 400 and 600 ft. the final reading was recorded at 160psi and o 70 F. When analyzing the data associated with Example #2. in length and constructed of carbon steel. it is important to note the relatively stable pressures and temperatures recorded. This portion of piping is underground and transports fuel from another portion of piping to an aboveground day storage tank system. and from the pipe’s interior surface to the #2 diesel fuel. In the two examples given. Given the above information. to the cooler exterior surface of the pipe.1 psi pressure drop. one can see this delay in energy transfer when one analyzes the fourth and fifth readings. respectively. the pipe is not absorbing energy from solar radiation incident upon the exterior surface. and all the way to the ground surface. Contained within the pipe was #2 diesel fuel. Also. then the test passes. from the pipe’s exterior surface to the pipe’s interior surface. The analysis of this pressure test’s results includes a comparison of the initial recorded pressure to other recorded pressures during the test and evaluation for a substantial pressure drop to confirm a failed test.

Barlow's Formula is the common method used to determine hoop stress in the wall of pipe. Arthur D Bosshart II TECO Energy reading. A failed test can be overlooked because of increased pressure from an increase in the contained substance’s temperature and failed tests may have actually passed due to a temperature decrease. Proposed Procedure The following procedure is proposed to be conducted in association with the current API 1110 pressure testing. the effects of hoop stress are negligible. Pressure levels observed during API 1110 pressure testing will not cause piping deformation because the observed pressure levels used during testing are well below the design pressure limits of the piping system. By monitoring the temperature of the contained substance in the piping during a pressure test. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 9 . If the temperature change of the contained substance is known. See Appendix A for an example calculation. The difference between the calculated and the measured pressure values is what must be analyzed.A. By eliminating the need to monitor the external surface temperature of the pipe. Minimal volume change occurs because a minimal piping deformation occurs therefore.601.8 as the stress in a pipe wall.601. then the energy change of the liquid can be used to determine the temperature change of the pipe eventually determining the thermal expansion of the pipe. F. This proposed procedure will account for temperature change during a pressure test to ensure compliance with the requirements of Table BPP table of Rule 62-762. the complexity of Fourier's heat transfer calculations and the need to monitor the ambient and the exterior pipe surface temperature can be eliminated. The contained substance’s temperature must be measured during testing and an expected pressure change must be calculated from the temperature data and compared to the measured pressure change. Hoop stress is defined in ASME B31. the potential for inaccuracies is decreased substantially and facilitates the development of an additional procedure that can be used in conjunction with the API 1110 pressure test method to meet the standards in Table BPP of Rule 62-762. acting circumferentially in a plain perpendicular to the longitudinal axis of the pipe and produced by the pressure of the fluid in the pipe.C.

between the theoretical calculated pressure(s) and the actual measured pressure(s) should be analyzed and an unaccounted volumetric flow determined. the theoretical calculated pressure can be determined.601.C.A. The next step is to gather referenced data for the known conditions and factors. the deviations. then the volume of the contained substance can be calculated by using the inside diameter of the pipe.. along with the compressibility of the contained substance. Once the length is determined. Piping as-built drawing or a process flow diagram (PFD) should be referenced to find the length of pipe that is to be isolated for testing. liquid. and the physical state of that contained substance (i. solid. Once the testing is completed and all data is gathered. the contained substance within the pipe. to determine a pass or a fail. if present.e. The test may also be broken into separate calculations if the need to bleed off or increase pressure occurs. but a temperature probe should also be used to take readings of the substance’s temperature contained within the isolated pipe. F. The pressure test should be performed in accordance with API 1110 monitoring the pressure and ambient temperature. This unaccounted volumetric flow can be compared to Table BPP found in Rule 62-762. and set forth below. Arthur D Bosshart II TECO Energy F. When the theoretical calculation(s) is complete. The first step is to identify known conditions and factors. It is important to be aware of the integrity of the temperature probe’s seal to assure that the temperature reading point is not a source of pressure loss. Please see Appendix E for a field simplified field method for determining compliance. gas). Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 10 .C. This calculation may be broken into two separate theoretical pressure calculations if circumstances such as those seen in Example #2 occur. The thermal expansion coefficients of the pipe material and the contained substance must be referenced. This will provide an explanation for such abnormal occurrences while maintaining the accuracy of the test.A. These include the material of which the pipe being pressure tested is constructed. Temperature of the contained substance should be monitored with the same regularity of the pressure readings.

Ideal Testing Conditions The proposed additional procedure to API 1110 accounts for temperature change and accurately calculates a volumetric loss from a piping segment that is pressure tested. An example of one scenario is if a pressure test is performed on an aboveground segment of piping where half is exposed to solar radiation and half Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 11 .2 gallons/hr 0.000 gallons. F.5 gallons/hr 1 gallons/hr Testing Using a spreadsheet developed for this purpose and using data from Example #1. However. Neither of the two examples actually monitored the temperature of the contained substance during testing and therefore these calculated examples are demonstrative only. Calculations were also conducted for Example #2 which was also determined to be a passing pressure test.000 gallons than 50000 gallons but less than greater than 100000 gallons 100000 gallons Leak Rates for Monthly 3 gallons/hr 4 gallons/hr 5 gallons/hr Testing Leak Rates for 1 gallon/hr 2 gallons/hr 3 gallons/hr Quarterly Testing Leak Rates for Annual 0. It was determined that 0. The pipe segment tested has a capacity less than 50. Arthur D Bosshart II TECO Energy Frequency of Testing Line Segment Capacity Line Segment Capacity greater Line segment capacity Less than 50. The greatest potential threat to the accuracy of the proposed addition to the API 1110 pressure test method is from the temperature gradients of the contained substance from which temperature readings are being recorded.161469 gallons/hr were unaccounted for during this test.2 gallons/hr or less is required to be in compliance. Therefore. there are a few scenarios that could potentially produce an inaccurate result.C. it is of the upmost importance to identify ideal testing conditions to optimize the accuracy of the results produced to ensure compliance with Table BPP in Rule 62-762. Please see Appendix E for a field simplified field method for determining compliance. therefore by referencing the Table BPP above it is found that an unaccounted volumetric flow of 0. it can be o determined that the pressure test in Example #1 was a passing test assuming a 1 F temperature change occurred. A full set of calculations of the theoretical pressure for Example #1 is shown in Appendix A.A.601.

the energy flow through the pipe to the contained substance on one end will be greater than on the other causing a temperature gradient across the pipe. and heat transfer equations but. It is a safe assumption to assume the portion of pipe exposed to solar radiation will absorb more energy than the portion of piping covered by the shade. Piping segments. Calculations can be conducted from weather data. Consequently. ∆T = 1. This would cause the calculations to represent that a greater volumetric loss had occurred and could possibly fail a passing test. These temperature gradients are illustrated below. the proposed procedure would become too complex and could lead to a greater potential for error. then the value of the theoretically calculated pressure will be higher because of a larger temperature change during the pressure test on the half exposed to solar radiation than on the half covered by shade. Temperature Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 12 . the chance for temperature gradients is minimized and testing can be conducted at anytime.5oF ∆T = 2. If the temperature readings of the contained substance are being measured on the warmer half of the pipe. where a portion of pipe greater than 10% is aboveground and the remaining portion is below ground. Arthur D Bosshart II TECO Energy is covered by shade. solar engineering equations. should be pressure tested separately so potential errors from temperature gradients can be avoided. The reverse is true if the temperature measurements were recorded from the cooler half of the pipe.5oF ∆T = 1oF ∆T = 4oF No Direct Exposure to Solar Radiation Direct Exposure to Solar Radiation To assure accurate results. If a pipe segment is entirely exposed to direct solar radiation or only exposed to diffused and reflected solar radiation. such piping should be tested during early morning or twilight hours to minimize temperature gradients. A failed test could pass because the theoretically calculated pressure would be lowered and would not account for the half of the pipe exposed to the solar radiation. where portions of piping are exposed to intense day time solar radiation.

F. Conclusions The existing API 1110 pressure test method is accurate unless a temperature change in the contained substance occurs. though linear thermal expansion will have an observable variation. If a large temperature change of the contained substance occurs (more than 5F). so if a comparison between the volumetric thermal expansion differences between a 4in pipe and a 6in pipe. This proposed method is to be used in conjunction with the API 1110 pressure test method which allows for highly accurate results that account for a temperature change during a test. the volumetric change is what must be noted when measuring pressure. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 13 . at most a 2F to 4F temperature rise. Changing pipe diameters in underground piping is prevalent in older industrial facilities. though highly unlikely. the volume of a contained substance can still be calculated.601. If changes in diameter occur within a piping segment isolated for pressure testing. if this additional procedure is used during API 1110 pressure testing. the temperature change of the piping will be very stable. it might create a larger radial temperature gradient within the 6in pipe and could provide a different end result than the 4in pipe. at a varying range of temperature change of the pipe material is small to begin with. Arthur D Bosshart II TECO Energy measurements should be recorded from the middle 20% of the piping segment isolated for testing. pressure testing should be conducted during early morning or twilight hours and during months where there is not a rapid temperature increase or decrease throughout the day.A. an accurate grade of pass or fail will be determined in accordance with Table BPP of Rule 62-762. Volumetric thermal expansion of the piping. the difference would be negligible.C. This is an unlikely scenario though during a one hour test. If the isolated pipe segment is underground. Outside of the temperature change of the contained substance. If the pressure test is conducted on above ground piping then the temperature change might be more unstable. This proposed method will allow the Department of Environmental Protection (DEP) to have full confidence that. If the above-mentioned actions are not possible.

Arthur Bosshart. representatives of Marathon Oil. Arthur D Bosshart II TECO Energy Acknowledgements The cooperation and assistance of the members of the Solid Waste Subcommittee of the Florida Electric Power Coordinating Group.A. Inc. Special thanks to Mr. TECO Energy. P. All queries regarding the proposed method and technical aspects should be directed to Mr. Randy Melton and Mr. Michael Petrovich of Hopping Green & Sams. adbosshart@tecoenergy. Stan Kroh of TECO Energy.. and the Florida Petroleum Council. Mr. is greatly appreciated.com Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 14 .

2007 3) American Society of Mechanical Engineers (ASME) B31. Arthur D Bosshart II TECO Energy Bibliography 1) API Recommended Practice 1110.8 .2003 Gas Transmission and Distribution Piping Systems Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 15 . March 1997 2) Chapter 62-762. Fourth Edition. Florida Administrative Code – Draft Rule – September 28.

37884 * 0.583333333 . the temperature change of the pipe is determined from the contained substance’s energy change by its temperature change ∆TP = Q/(MP*CpP) = 4033. 37884 .3125^2)* 11275.3953 * 1 = 149. Volume is in gallons.VLo (Initial Volume @ Initial Temperature) Vp = (3.4681151 * 65. 3) Mass of the pipe is calculated MP = VP*DP = 270. Temperature is given in degrees Fahrenheit 7) Linear Thermal Expansion of Piping (Carbon Steel) Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 16 . density is in pounds per gallon 4) Mass of contained substance ML = DL*VL = 6.) LTo = 11275.36954953 = 17680.00046 * 325581. density is in pounds per gallon 5) Energy change of the substance from the measured temperature change is calculated Q = ML*CpL*∆TL = 9380* 0.30538 (The length of pipe in inches at initial temperature) 3 3 VLo = 325581.3125 in.14 ro = 3. The outside radius of the pipe in inches.12) = 3.7 * 1400 = 9380 . Volume is in gallons.4 / (17680.7674419 -volume is converted to in3 2) Volume of pipe material is calculated π = 3.43 * 1 = 4033. Energy is given in BTU 6) Rearranging the equation from step 5. (Referenced Value. Arthur D Bosshart II TECO Energy Appendix Appendix A A calculation walkthrough step-by-step for Example 1: 1) Volumetric Thermal Expansion of Liquid (#2 Diesel Fuel) ∆VL = βL*VLo*∆TL = 0.0043) – 1400 = 270.4 .4681151 gal.30538)*.3953 in (Value must be converted to in ) 2 Vp = (π*ro *LTo) .14*(3.

Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 17 .1 . The volume is given in cubic inches 9) The volume change of the pipe is calculated ∆Vp = VpT2 – VpTo = 325590. From here the unaccounted volume is divided by the testing duration and the number yielded can be compared to the BPP Table to determine compliance.1 = 140. an adjusted thermal expansion coefficient for the substance is calculated.4953 .3953 * 1) = 0.315144785 .00043205 .30538 * 3.6674419 .PAM )*VLo/ ά = ((200.3953 = 9.21260126 / 1.1614693 gallons/hr . The answer is given in cubic inches 11) Using the overall change in volume.97 – 234) * 1400) / 217500 = -0.3166667 = 0. This is the volume change with respect to the contained substance. Unaccounted volume is found by comparing the difference in pressure changes and rearranging the pressure formula. The answer is given in gallons. ∆VLa = (PTC .6674419 / 325581. Linear expansion is first calculated then volumetric 8) Volume of the pipe at the final temperature is calculated from its linear thermal expansion VpT2 = πri2LT2 = 3.325581.3166667 hr -0.4953 . βA = ∆V / (VLo*∆TL) = 140.9. if the initial volume value used in the equation is in gallons . The equation below is arranged to use compressibility but further manipulation can form an equation to use the bulk modulus of elasticity “P” coefficient = ∆P = (∆V/VL0) / ά = (140.3953)* 217500) = 93. The answer is given in PSI 13) The theoretical calculated pressure is the sum of the theoretical calculated pressure change and the actual measured initial pressure.97 .6674419 / (325581.∆VP = 149. The volume change is given in cubic inches 10) The overall change in volume accounts for the expansion rates of the substance and the pipe ∆V = ∆VL .62052 = 325590.583333333 = 0. The bulk modulus is the inverse of the substances compressibility.03252 * 11275. Arthur D Bosshart II TECO Energy ∆Lp = βp* LTo *∆Tp = 0.14 * 3.0000078 * 11275.21260126 79min /60 = 1. Answer is given in oF-1 12) The theoretical pressure change is calculated using the bulk modulus of elasticity of the substance.7674419 .

5% C Calculated Field (DO NOT EDIT) Select Substance contained in Pipe Enter Data if Selections are not Found in List #2 Diesel Fuel Oil Testing Conditions and Data Collected Drop Down List Auto populated if selection is on list Pretest Data 6. Data entry section of the spread sheet: Select Pipe Material Input Field Carbon Steel 0.625 in Pipe Outside Diameter See Table on Sheet 3 0.065 in Pipe Inside Diameter See Table on Sheet 3 6.28 in Pipe Schedule See Table on Sheet 3 1400 gallons Initial Volume of Liquid o -1 F Thermal Expansion Coefficient of Piping Material o -1 F Thermal Expansion Coefficient of Liquid psi Compressibility of Liquid o BTU/lb F Heat Capacity of Substance in Pipe (Only if Substance is not shown in above List) BTU/lb oF Heat Capacity of Pipe (Only if Piping Material is not shown in above List) o BTU/(hr F in) Heat Conductivity (Only if Piping Material is not shown in above List) lbs/gallon Density of Substance in Pipe (Only if Substance is not shown in above List) lbs/gallon Density of Piping Material (Only if Piping Material is not shown in above List) This is the calculation portion of the spread sheet: Theoretical Pressure Change with Bulk Elastic Properties of Diesel Compressibility ∆P = (∆VL2/VL0) * ά ά = Compressibility (#2 Diesel) ∆P = Change in Pressure ά 217500 psi ∆P 93.97 psi ∆VL = βL*VLo*∆TL ∆VL = Change in Volume of Liquid βL = Thermal Expansion Coefficient of Liquid Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 18 . The spread sheet shows entries made for analyzing Example #1. Arthur D Bosshart II TECO Energy Appendix B The following spreadsheet was used for developing the proposed method and for calculation purposes.

30538 in 939.0000078 o F -1 LTo 11275.3953 in3 ∆TL 1 o F ∆VL 149.60878 ft ∆Tp 3.4953 in3 ∆Vp = VpT2 – VpTo ∆Vp = Change in Piping Volume ∆VP 9. Therefore. ro 3.583333333 o F Use heat transfer Equation ∆Lp 0. Arthur D Bosshart II TECO Energy VLo = Initial Liquid Volume ∆TL = Change in Temperature βL 0.62052 in VpT2 325590.315144785 in VpTo = πri2LTo *assuming no residual air pockets in pipe VpTo = Volume of Pipe @ Initial Temperature ri = radius of inside piping diameter ri 3.00046 o F -1 VLo 325581.3125 in Ape 234623.5581395 Pipe Surface Area Ape = 2πro2 + 2πroLTo Ape = Surface Area of Pipe Exterior ro = Radius of Pipe Exterior *assume that the minimal increase in piping surface due to temperature rise has no effect on heat transfer from the pipe exterior surface to the liquid contained within the pipe.0325 in VpTo 325581.7674419 in3 232. piping surface area at initial temperature is used for calculation.4484 in2 Volumetric Thermal Expansion of Piping (Carbon Steel) ∆Lp = βp* LTo *∆Tp βp = Thermal Expansion Coefficient of Piping Material LTo = Length of Pipe @ Initial Temperature ∆Tp = Change in Piping Temperature βp 0.1 in3 Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 19 .3953 in3 VpT2 = πri2LT2 VpT2 = Volume of Pipe @ Final Temperature LT2 = Length of Pipe @ Final Temperature LT2 11275.

Mass of Substance in Pipe ML = DL*VL MP = Mass of Substance contained in Pipe DP = Density of Substance contained in Pipe VL 1400 gallons DL 6. Energy in Substance Q=ML*CpL*∆TL Q = Heat CpL = Heat capacity of Substance BTU/lb CpL 0.0043 gallons DP 65.43 o F Q 4033. Arthur D Bosshart II TECO Energy Overall Change in Volume ∆V = ∆VL .12 o F o ∆TP 3.583333333 F This is your results portion of the spread sheet: Unaccounted Volume ∆VLa = (PTC .37884 lbs.6674419 in3 Mass of Piping MP= DP*VP ML = Mass of Isolated Piping DL = Density of Piping Material VP 270.PAM )*VLo/ ά ∆VLa = Calculated Volume Difference associated with pressure change PTC = Theoretical Calculated Pressure PAM = Actually Measured Pressure Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 20 .4 BTU Temperature Change of Pipe ∆TP = Q/(MP*CpP) CpP = Heat Capacity of Pipe Material BTU/lb CpP 0.7 lbs/gallon ML 9380 lbs.4681151 gallons 1 in^3 = .36954953 lbs/gallon 1 kg/m^3 = .008345404 lbs/gallon MP 17680.∆VP ∆V = Overall Change in Volume ∆V 140.

21260126 gallons ∆VLa /hr 0. and during normal testing conditions an extreme temperature change will not occur over single test duration.6 in.1614693 gallons/hr Appendix C Assumptions 1) A minimal increase in piping surface due to temperature rise has no effect on heat transfer from the pipe exterior surface to the liquid contained within the pipe. 4) The radial temperature gradient of the pipe material is negligible because pipe walls are less than . piping surface area at initial temperature is used for calculation. No volume change occurs because no deformation of the piping material occurs.97 psi ∆VLa -0. 3) Hoop Stress on piping does not cause piping deformation because pressure levels used during testing are well below the design pressure of the piping system. Appendix D Nomenclature ά = Compressibility (#2 Diesel) ∆P = Change in Pressure ∆VL = Change in Volume of Liquid βL = Thermal Expansion Coefficient of Liquid VLo = Initial Liquid Volume ∆TL = Change in Temperature Ape = Surface Area of Pipe Exterior Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 21 . 2) The system to be tested is assumed to be comprised entirely of a homogeneous liquid. Therefore. Arthur D Bosshart II TECO Energy PTC 200.

4 PSI change per unit of temperature will be known as the “P” coefficient in the pressure testing packet in appendix I. The “P” Coefficient is found by relating compressibility to a change in volume and defining a change in temperature o between the initial temperature (Ti) and the final temperature (T f) to be . Using equations 1 through 12 found in Appendix A of “Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance” and defining referenced coefficients for liquid Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 22 .1 F change in temperature within a perfectly isolated volume.1 F. Arthur D Bosshart II TECO Energy ro = Radius of Pipe Exterior βp = Thermal Expansion Coefficient of Piping Material LTo = Length of Pipe @ Initial Temperature ∆Tp = Change in Piping Temperature VpTo = Volume of Pipe @ Initial Temperature ri = radius of inside piping diameter VpT2 = Volume of Pipe @ Final Temperature LT2 = Length of Pipe @ Final Temperature ∆Vp = Change in Piping Volume ∆V = Overall Change in Volume ML = Mass of Isolated Piping DL = Density of Piping Material MP = Mass of Substance contained in Pipe DP = Density of Substance contained in Pipe Q = Heat CpL = Heat capacity of Substance CpP = Heat Capacity of Pipe Material Appendix E Simplified Field Method o For #2 Diesel it is found that a linear pressure change of 9. This 9.4 PSI occurs for every .

By subtracting the APT defined for the given piping volume from the PTc. See Equation 4. pipe density. PTc = Pi + 9. When the pressure testing is complete the magnitude factor (MF) should be multiplied by 9. pipe heat capacity. liquid thermal expansion.Pam (2) Procedure Simplified Find as-built drawings of piping system to be pressure tested and note the lengths of each section that is to be isolated.4 PSI and then added to the initially measured pressure (Pi) from the beginning of the test to determine the theoretically calculated pressure (PTc). APT = ((∆VLa/hr)(ά))/VLo (1) APT = PTc . APT is the allowable pressure difference between the theoretically calculated pressure (P Tc) and the actually measured pressure (Pam). liquid density. Using the piping volume that was calculated prior to testing. Calculate the volume within the section of pipe that is to be isolated for pressure testing using the following equation: 2 VTo = πr L (3) o Given that 9.4 PSI occurs for every . Determine the size of piping and the schedule of piping then find the inside radius of the pipe using reference material.4(MF) (4) During the test. and liquid heat capacity the “P” coefficient for any substance may be found.C.A. The Allowable Pressure Tolerance (APT) is calculated by defining an acceptable volumetric loss which for purposes of compliance in Florida is defined to be .2 gallons/hour (∆VLa/hr) by Table BPP within 62-762 F. Equation 1 is the formula used for calculating ATP where compressibility (ά) and piping volume at the initial temperature are shown (V Lo).1 F change in temperature.1 F to determine the magnitude factor to be used later. the noted temperature change o during the testing period should be divided by . piping thermal expansion. the APT lookup table must be present. the APT can be found using the APT lookup table. the lower limit of the actually measured Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 23 . Arthur D Bosshart II TECO Energy compressibility.

75 0. Appendix F APT Lookup Table o 9.17 0.19 25.21 36.50 90.17 0.38 67.75 22.12 12.68 93.71 25.2 2400 13.2 2700 12.2 1400 23.54 20.64 0.19 32.59 18.07 0.54 21.2 1900 17.03 17.17 0.13 21.39 27.61 62.91 0.13 0.48 19.2 1000 32.77 10.31 21.2 4200 7.2 3900 8.55 49.59 11.13 24.31 17.63 43.84 46.2 1800 18.75 hr Test Duration 1 hr Test Duration 1.64 0.17 30.42 23.19 0.2 3600 9.63 0.78 0.54 19.19 33.37 0.98 40.65 15.50 18.43 15.91 25.99 19.1 ∆ F Test Duration .10 0.59 10.2 1600 20.2 3500 9.88 13.32 12.) APT (PSI) APT (PSI) APT (PSI) APT (PSI) ∆VLa /hr 500 65.75 29.2 800 40.50 0.2 2100 15.2 3100 10.50 0.66 0.32 0.55 16.30 0.89 31.73 0.94 16.66 39.99 20.66 27.25 45.60 12.2 4300 7.59 16.75 26.2 2000 16.2 2500 13.61 13.25 0.64 28.2 3400 9.83 50.07 38.25 0.31 0.78 54.39 0.18 18.2 1500 21.88 14.50 54.19 0.11 20.30 31.75 27.2 1700 19.4 PSI / .38 65.37 11.2 3800 8.95 15.99 38.83 19.45 14.61 0.46 41.34 0.2 Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 24 .25 15.2 2600 12.15 13.36 12.79 15.43 59.54 18.2 3300 9.97 81.62 34.63 108.14 77.42 72.2 4100 7.21 0.00 36.2 1300 25.19 0.96 10.00 108.05 17. If the measured pressure during the duration of a pressure test falls below this defined lower limit then the test fails.38 0.50 0.2 2900 11.50 0.38 72.20 13.08 16.2 2300 14.08 15.19 36.75 0.26 15.33 60.56 0.5 Piping Volume (Gal.59 16. Arthur D Bosshart II TECO Energy pressure can be defined.72 29.2 1100 29.65 15.76 14.25 hr Test Duration 1.13 22.2 900 36.10 18.89 28.25 43.40 21.25 87.18 16.2 700 46.73 20.38 0.2 3000 10.17 22.00 18.25 48.91 23.2 4000 8.16 10.2 1200 27.31 54.2 2800 11.70 17.06 12.77 24.82 11.05 0.2 2200 14.2 600 54.59 31.54 0.2 3200 10.75 130.89 13.77 0.52 14.10 33.2 3700 8.14 24.10 0.

00 60. Test Duration Allowable Pressure Tolerance "APT" (PSI) 1 hr.06 11.94 9.70 10. The volume of the pipe that is to be isolated was calculated to have a capacity of 1400 gallons.2 4600 7.00 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 Piping Volume (Gallons) Appendix H Simplified Field Method Sample Calculation For example.00 .2 4500 7.00 20.25 9.57 13.80 9.50 0.41 9. Arthur D Bosshart II TECO Energy 4400 7.88 13.88 0.75 hrs.2 4900 6. in diameter and had a schedule 40 wall thickness.18 0. Test Duration 1.2 Appendix G Compliance Curve Compliance Curve #2 Diesel APT = ((∆VLa /hr)*ά) / VLo 120. Test Duration 1.46 11.82 14.00 0.00 100.25 hrs.2 4700 6.32 0.89 12.36 14. The line was properly packed and the initial temperature and pressure readings Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 25 .33 13.05 0. an underground pipe that contains #2 diesel fuel is pressure tested in the state of Florida.59 0.53 8.2 4800 6.66 8.09 9.2 5000 6.08 14.10 13.67 12.83 0.5 hrs.00 40.88 11.26 11. Before the test it was determined that the pipe was 6in. Test Duration 80.

the theoretically calculated pressure (PTc) is determined. we find that for a piping system of 1400 gallons. The test lasted 1.4(MF) = 100 PSI + 9.5 hours and the final temperature and o pressure readings were 71.4 PSI Using the APT lookup table.1 F and 171 PSI respectively. The final reading is greater than the lower limit therefore the pressure test passes.4 PSI occurs for every o .61 PSI.61 PSI = 156.79 PSI The final temperature reading from the test was 171 PSI.4 PSI(11) = 203. PTc = Pi + 9. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 26 . Lower Limit = 203. o o o MF = (71. the lower limit for compliance is determined. See Appendix J to view the completed Line Pressure Testing form using this example.1 F . Is the piping system in compliance? Using the simplified procedure we know that a linear pressure change of 9. Arthur D Bosshart II TECO Energy o were 70 F and 100PSI respectively.1 F = 11 Next. Next.1 F change in temperature within a perfectly isolated volume therefore the magnitude factor (MF) is first calculated. the allowable pressure tolerance (APT) is 46. The magnitude factor has no units.70 F)/.4 PSI – 46.

Line 13 – Determine the lower limit value by subtracting line 11 from line 12. Line 2 – After the line is properly packed and pressurized the desired test pressure. which in this example is 1. Line 10 – Divide the value from line 9 by 0. Line 1 -.5hrs. Enter this value into line 11. Test Data Before the first temperature and pressure readings are recorded. Line 12 -. the piping segment being pressure tested must be properly “packed. divide 90 by 60 to convert the test duration to hours. Line 5 – When testing is complete enter the final pressure reading into line 5.The facility representative should identify an accurate pipe capacity through calculation or best engineering judgment. Line 7 – Enter the time which the test ended into line 7. Post Test Calculation Line 8 – Subtract line 7 from line 4 and enter the length of the test. enter the initial pressure reading once testing begins into line 2. Information regarding the pipe capacity and the contained substance should be given to the entity or individuals conducting the pressure test prior to testing. Line P – Values for the “P” coefficient may be found on page 2 of the DEP Line Pressure Testing Packet in the “P” Coefficient Lookup Table. Line 4 – Enter the time which testing begins into line 4. Please reference for proper packing procedures section 3. Enter this value into line 12. Arthur D Bosshart II TECO Energy Appendix I Line Pressure Testing Packet Instructions Pretest Pretest data should be acquired prior to pressure testing. Line 6 – Enter the final temperature reading into Line 6.1 and enter it into Line 10. then simply multiple the value by -1 and enter the positive number into line 9. for example. Line 11 – Determine the theoretically calculated pressure by multiplying the value from line P by line 10 and adding the product of the multiplication to the initial pressure reading on line 2. If this value is a negative number. Enter this value into line P. into line 8. If a test. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 27 . lasts 90 minutes. The lower limit is the limit that that the pressure cannot drop below during testing to be compliant.Values for the allowable pressure tolerance “APT” may be found on page 3 of the DEP Line Pressure Testing Packet in the APT Lookup Table. Line 3 – Enter the initial temperature reading once testing begins into line 3. in hours. Enter this value into line 13.” Meaning the piping segment must be completely filled with the contained substance with no vapor or air pockets.7 of API Recommended Practice 1110 Fourth Edition. March 1997. Use the Facility Identified Isolated Piping Segment Capacity found on line 1 and the test duration found on line 8 to determine the APT value. Line 9 – Subtract line 6 from line 3 and enter the change in temperature into line 9.

otherwise circle the compliance determination of PASS.1 F = ____________________________ (10) “The Magnitude Factor is unit less”” o Theoretically Calculated Pressure (PTc) PTc = line 2 + line P x line 10 = _________________ F (11) “units of Temperature must be given in oF” Allowable Pressure Tolerance (APT) APT = _____________________________________ PSI (12) “units of Pressure must be given in PSI” The APT is found using the table on page 3 of the pressure testing packet. on (14) line 5? Y N Test Result If the lower limit pressure (Lower Limit). Lower Limit Lower Limit = line 11 – line 12 = __________________ PSI (13) “units of Pressure must be given in PSI” Is the lower limit pressure (Lower Limit). PASS FAIL Pressure Test Conducted by _____________________________________ Pressure Test Technician _____________________________________ Technician Signature _____________________________________ Facility Representative _____________________________________ Facility Representative Signature _____________________________________ Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 28 . on line 13. March 1997” Initial Test Data Initial Pressure Reading (Pi) ____________________________ (2) “units of pressure must be given in PSI” Initial Temperature Reading (Ti) ____________________________ (3) “units of Temperature must be given in oF” Time Began ____________________________ (4) Final Test Data Final Pressure Reading (PF) ____________________________ (5) “units of pressure must be given in PSI” Final Temperature Reading (TF) ____________________________ (6) “units of Temperature must be given in oF” Time Ended ____________________________ (7) Post Test Calculation Test Duration (t) t = line 7 – line 4 = __________________________ Hours (8) “units of time must be given in hours” o Temperature Change (∆T) ∆T = line 6 – line 3 = __________________________ F (9) “units of Temperature must be given in oF” o Magnitude Factor (MF) MF = line 9 / 0. Arthur D Bosshart II TECO Energy DEP Line Pressure Testing Worksheet Facility Owner _______________________ Date _________________ Facility Name _______________________ Facility ID _________________ Line Segment Tested _______________________ Pretest Data Data Description Data Entry Line Number Contained Substance ____________________ P=_________________________ P The “P” coefficients can be found using a referenced value of the contained substance found on page 2 of the pressure testing packet. on line 13. is greater than the final pressure (PF) reading. find the associated APT value. on line 5 then circle the compliance determination of FAIL. less than the final pressure (P F) reading.7 of API Recommended Practice 1110 Fourth Edition. Using the “Facility Identified Isolated Piping Segment Capacity” on line (1). Facility Identified Isolated Piping Segment Capacity (V) ___________________________ (1) Capacity must be given in gallons Test Data Is the test segment properly packed? Y N “For proper line packing procedures refer to Section 3.

4 Biodiesel #6 Fuel Oil Benzene Methanol Ethanol Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 29 . Arthur D Bosshart II TECO Energy “P” Coefficient Lookup Table Enter the correct “P” coefficient into the DEP Line Pressure Testing Worksheet into “line P” Gasoline #2 Diesel 9.

59 11.2 3000 10.08 15.66 39.13 0.59 16.43 15.55 49.72 29.61 0.63 0.97 81.77 10.2 300 108.18 16.83 19.66 0.50 271.10 0.99 20.50 90.25 45.61 62.34 0.84 46.2 3900 8.10 0.2 2000 16.16 10.54 18.37 11.2 1900 17.25 0.2 1000 32.63 108.2 3500 9.89 13.76 14.38 0.2 2400 13.2 2200 14.50 0.2 3800 8.50 18.31 21.25 48.30 0.2 600 54.14 24.25 15.06 12.39 27.56 0.07 0.75 29.50 0.15 13.38 67.50 0.2 1100 29.40 21.2 400 81.17 0.38 72.07 38.78 54.48 19.54 0.2 1600 20.37 0.25 217.2 2700 12.75 145.2 2300 14.73 20.13 21.83 50.09 9.66 27.62 34.31 54.50 0.) APT (PSI) APT (PSI) APT (PSI) APT (PSI) ∆VLa /hr 100 326.08 14.19 32.89 28.2 3400 9.56 108.79 15.75 hr Test Duration 1 hr Test Duration 1.2 1200 27.94 163.2 3600 9.94 16.43 59.18 18.2 4200 7.50 0.68 93.2 4400 7.73 0.31 0.11 20.99 19.88 14.38 0.00 108.50 0.64 0.59 18.17 30.17 0.75 130.25 43.91 23.75 27.2 200 163.2 2800 11.1 ∆oF Test Duration .2 4100 7.2 2600 12.2 4500 7.36 12.55 16.91 25.70 17.26 15.75 0.61 13.30 31.75 652.19 0.41 9.17 0.50 54.13 0.2 800 40.64 0.39 0.13 22.18 0.19 33.2 3200 10.60 12.89 12.75 0.54 21.19 25.2 1700 19.77 0.54 19.12 12.32 0.08 16.5 Piping Volume (Gal.10 33.59 16.19 0.36 14.82 11.10 18.2 3100 10.65 15.2 1400 23.2 500 65.50 0.78 0.2 4600 7.2 3700 8.52 14.99 38.2 2900 11.42 72.77 24.03 17.2 3300 9. Arthur D Bosshart II TECO Energy APT Lookup Table #2 Diesel Fuel Oil 9.25 435.54 20.82 14.05 0.21 36.00 181.88 13.21 0.75 26.91 0.2 2500 13.95 15.2 1800 18.2 4000 8.20 13.17 22.75 135.31 17.88 326.98 40.96 10.05 17.2 1300 25.25 9.59 10.2 900 36.25 hr Test Duration 1.25 87.42 23.89 31.13 24.71 25.19 36.4 PSI / .63 43.2 700 46.25 0.65 15.33 60.2 1500 21.59 31.13 217.46 41.19 0.00 36.46 11.2 Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 30 .64 28.38 65.14 77.00 543.45 14.2 2100 15.67 12.25 0.2 4300 7.75 22.00 18.32 12.83 0.

00 9.55 4.2 5400 6.44 7.2 8200 3.2 5200 6.2 7600 4.66 12.2 7300 4.84 5.2 6200 5.2 8500 3.2 7100 4.2 7800 4.88 11.77 0.52 0.94 6.2 9000 3.96 7.47 7.88 8.2 8000 4.73 5.03 5.2 9600 3.2 6100 5.63 7.18 6.88 5.19 0.18 7.37 9.68 0.06 10.2 8100 4.54 11.47 4.2 6800 4.2 9200 3.09 0.36 0.2 6700 4.02 0.30 7.37 10.11 7.98 5.2 5900 5.02 8.66 9.53 7.2 5800 5.71 4.85 7.08 0.87 6.20 0.26 11.73 6.2 6400 5.18 6.07 12.2 8400 3.38 11.49 8.88 7.63 5.13 8.60 6.18 5.93 7.2 4800 6.40 7.06 10.50 9.80 8.16 8.31 0.89 11.60 0.06 0.91 9.82 0.70 0.89 0.63 9.93 5.2 9400 3.2 6300 5.35 7.88 9.25 0.80 0.15 8.32 0.80 9.66 8.94 0.2 8600 3.2 7500 4.2 8700 3.10 6.45 8.72 7.06 0.12 9.06 11.97 8.80 6.72 7.2 8800 3.30 6.71 11.88 0.06 6.2 7900 4.75 5.94 0.13 5.53 6.37 10.2 6900 4.68 5.51 6.26 7.2 7400 4.2 6500 5.50 0.86 0.41 5.91 7.46 12.66 6.22 11.70 0.98 7.51 4.71 8.96 0.04 0.47 0.2 5600 5.27 8.58 5.2 6600 4.53 5.2 6000 5.08 5.74 0.59 8.50 10.35 5. Arthur D Bosshart II TECO Energy 4700 6.94 9.88 0.55 7.83 6.2 9500 3.2 5700 5.2 9300 3.02 6.83 7.86 0.91 10.10 13.63 4.25 9.65 0.70 10.33 0.33 13.65 7.80 8.25 7.2 5100 6.2 8300 3.55 0.12 6.69 8.26 12.88 13.2 8900 3.77 9.00 6.80 7.94 6.05 0.24 6.41 0.63 7.17 0.78 6.04 8.2 5500 5.43 4.40 8.66 6.59 0.25 0.32 7.2 7000 4.04 7.21 7.06 0.29 5.40 4.57 13.72 6.59 0.2 7700 4.63 10.78 5.89 6.79 0.77 10.13 7.90 8.25 8.53 10.2 5000 6.35 8.24 5.2 4900 6.21 10.37 0.26 0.2 9100 3.45 0.04 7.44 6.2 Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 31 .53 8.2 7200 4.59 4.79 5.47 5.40 8.2 5300 6.24 9.37 6.32 0.87 0.59 0.55 9.46 0.16 0.77 9.67 4.06 8.58 6.

75 hrs. Test Duration 1. Test Duration Allowable Pressure Tolerance "APT" (PSI) 1 hr.26 4.73 0.48 5.00 100.33 4.00 .2 9900 3.00 40.2 Compliance Curve #2 Diesel APT = ((∆VLa /hr)*ά) / VLo 120.2 9800 3.35 5.39 5.61 6.53 0.59 0.2 10000 3.36 4.00 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 Piping Volume (Gallons) Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 32 .55 6. Test Duration 1.00 60.44 6.00 0.25 hrs. Arthur D Bosshart II TECO Energy 9700 3.30 4.00 20.44 5. Test Duration 80.66 0.49 6.5 hrs.

Arthur D Bosshart II TECO Energy Appendix J Completed Line Pressure Testing Worksheet Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 33 .

1 F (Define your temperature change as .30538)*. pipe. 1) Volumetric Thermal Expansion of Liquid (#2 Diesel Fuel) This is the change in volume due to the change in temperature./gal (Referenced Coefficient. We are using a 6 in. (Referenced Value.3953 in (Value must be converted to in ) 2 Vp = (π*ro *LTo) . 5) Energy change of the substance from the measured temperature change is calculated.36954953 = 17680. Arthur D Bosshart II TECO Energy Appendix K Step-by-Step Calculation of the “P” Coefficient The “P” Coefficient is found by relating compressibility to a change in volume and defining a change in temperature between the initial temperature (Ti) and the final temperature (Tf) to be o o . must be in pounds per gallon) VP = 270.4681151 gal. must be in F ) 3 3 VLo = 325581. 4) Mass of contained substance This is calculated to determine energy transfer. we will use the capacity of one of our actual piping systems.VLo (Initial Volume @ Initial Temperature) Vp = (3. Must be in gallons) ML = DL*VL = 6.4 PSI occurs for every . (Initial volume @ the initial temperature.3953 in (Value must be converted to in ) o o ∆TL = Tf – Ti = . o -1 o -1 βL = .1 F) 3 ∆VL = βL*VLo*∆TL = 0.1 F. Answer must be given in gallons. must be in pounds per gallon) VLo = 1400 gal.14*(3.0043) – 1400 = 270.00046 F (Referenced coefficient. This calculation is independent of the amount of volume but requires an initial value for volume to begin the calculation of the “P” coefficient.3953 * .1 = 14. In the example below.30538 (The length of pipe in inches at initial temperature) 3 3 VLo = 325581.) LTo = 11275. 3) Mass of the pipe is calculated The mass must be calculated to determine energy transfer.3125^2)* 11275. DL = 6. For #2 Diesel it is found that a linear pressure change of 9. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 34 . Subtracts the outside volume if pipe was a solid cylinder from the inside capacity of the pipe. 37884 lbs.14 ro = 3. DP = 65. The outside radius of the pipe in inches.00046 * 325581./gal (Referenced Coefficient.7 lbs. π = 3.36954953 lbs.4681151 gal.3125 in.1 F change in temperature within a perfectly isolated volume. This is the amount of piping material in in .4681151 * 65.7 * 1400 = 9380 lbs. (From Equation 2) MP = VP*DP = 270.97674419 in 2) Volume of pipe material is calculated 3 This is not the capacity of the pipe.

F (Referenced Coefficient. ML = 9380 lbs. 8) Volume of the pipe at the final temperature is calculated from its thermal expansion This is used to determine the overall change in volume with respect to all thermal expansions affecting the isolated system. 3 VpT2 = 325582.12 BTU/lb.043 BTU/lb. must be in F ) LTo = 11275.3583333333 F 7) Thermal Expansion of Piping (Carbon Steel) The Thermal Expansion will not substantially vary from material to material and therefore will not affect the determined value of the “P” Coefficient.3583333333 F (From Equation 6) ∆Lp = βp* LTo *∆Tp = 0. Must be in “BTU/lb.14 * 3.325581.0315144785 in.97674419 in (From Equation 1) 3 ∆VP = .34 BTU (From Equation 6) o o CpP = .3053 in (From Equation 8) 3 3 VLo = 325581.0325 in.30538 * .91 in 10) The overall change in volume accounts for the expansion rates of the substance and the pipe. π = 3.1 F) Q = ML*CpL*∆TL = 9380* 0.0315144785 in. F (Referenced Coefficient. (From Equation 4) o o CpL = . Arthur D Bosshart II TECO Energy This is calculated to determine energy transfer from the pipe material to determine the temperature change of the pipe material and eventually determine the thermal expansion of the pipe.43 * .3953 in (Value must be converted to in ) 3 ∆Vp = VpT2 – VLo = 325582. the temperature change of the pipe is determined from the contained substance’s energy change by its temperature change.1 = 403. (From Equation 3) o ∆TP = Q/(MP*CpP) = 403. Must be in “BTU/lb.34 BTU 6) Temperature Change of Piping Material Rearranging the equation from step 5.37884 lbs.3053 in 9) The volume change of the pipe is calculated This is the volume change of the pipe due to thermal expansion. Q = 403.0325 * (11275.3583333333 = 0.91 in (From Equation 9) Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 35 .12) = . F”) MP = 17680.315144785) = 325582.34 / (17680.0000078 * 11275.3953 = 0. 3 ∆VL = 14.3053 .1 F (Define your temperature change as . (From Equation 7) 2* + 2 3 VpT2 = π*ri (LTo ∆Lp) = 3.30538 in. (The length of pipe in inches at initial temperature) o ∆Tp = .30538 + . o -1 o -1 βp = . The differences from material to material are negligible. F”) o o ∆TL = Tf – Ti = .0000078 F (Referenced coefficient.30538 (The length of pipe in inches at initial temperature) ∆Lp = 0.14 ri = 3.37884 * 0.) LTo = 11275. The inside radius of the pipe in inches. (Referenced Value.

Compressibility must be in psi) “P” coefficient = ∆P = (∆V/VL0) / ά = (14. given in hours) APT = (((∆VLa/hr)(ά))/VLo)*t = ((0.97674419 .2 gallons/hour (∆V La/hr) by Table BPP within 62-762 F.3953) * 217500) = 9.0.5 = 46.2 gal/hr (This is the minimal accepted leak rate defined by environmental authority) ά = 217500 psi (Compressibility of #2 Diesel) VLo = 1400 gal. Equation 1 is the formula used for calculating ATP where compressibility (ά) and piping volume at the initial temperature (VLo) are accounted used in determination. The bulk modulus is the inverse of the substances compressibility. We will use the referenced and calculated values from Appendix K.2 * 217500)/1400)*1.91 = 14. APT is the allowable pressure difference.06674419 in (From Equation 11) 3 3 VL0 = 325581.61 psi Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 36 . The theoretical pressure change is calculated using the bulk modulus of elasticity of the substance.06674419 / 325581. defined by an environmental authority. between the theoretically calculated pressure (PTc) and the actually measured pressure (Pam). 3 ∆V = 14. 1) APT = (((∆VLa/hr)(ά))/VLo)*t ∆VLa/hr = 0. Arthur D Bosshart II TECO Energy 3 ∆V = ∆VL .06674419 in 12) Determination of the “P” Coefficient. (Duration of test.397 psi Appendix L Step-by-Step Calculation of a Specific APT Value The Allowable Pressure Tolerance (APT) is calculated by defining an acceptable volumetric loss which for purposes of compliance in Florida is defined to be .A.5 hrs. (Value must be in Gallons) t = 1.C.∆VP = 14.3953 in (Value must be converted to in ) ά = 217500 psi (Referenced Coefficient. The equation below can be arranged to use compressibility or the bulk modulus of elasticity.