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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

The pressure will vary depending on the volumetric thermal expansion rate of #2 diesel fuel and the piping material. Without monitoring the temperature of the substance within the pipe. Currently. 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. and energy transfers between materials. schedule of the piping. 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. 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 a potential deficiency of this test. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 4 . initial ambient temperature. there will be a substantial delay between the ambient or environmental temperature change and the temperature change of the substance. The temperature change is determined by the thermal conductivity of the piping material. These relationships are described in Fourier's law. Fourier's law describes linear heat flow rate between two surfaces. energy transfer is the reason why a substance’s temperature will increase during a test. the heat capacity of the liquid. initial exterior pipe surface temperature. 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. If a portion of the piping is exposed to the sun the exterior surface temperature of the piping will increase. Given that the piping section being tested is isolated. initial interior pipe surface temperature and final interior pipe surface temperature. final exterior pipe surface temperature. 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. If the heat capacity of the contained substance and thermal conductivity of the substance’s surroundings are accounted for. Field Tests and Analysis For purposes of this paper. final ambient temperature. This is because liquids are not easily compressible like gases. Arthur D Bosshart II TECO Energy to 100 psi. pressure changes. the energy flux. This reasoning is not accurate.

m.m. Arthur D Bosshart II TECO Energy Example #1: 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 5 . FL from 2:00 p. to 3:19 p. 2007 located in Apollo Beach.

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

The test was performed on a Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 7 . 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. 2007 located in Apollo Beach. FL from 3:20 p.m.m.

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

acting circumferentially in a plain perpendicular to the longitudinal axis of the pipe and produced by the pressure of the fluid in the pipe. By eliminating the need to monitor the external surface temperature of the pipe. Arthur D Bosshart II TECO Energy reading. F. 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. 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 difference between the calculated and the measured pressure values is what must be analyzed.A. If the temperature change of the contained substance is known. the effects of hoop stress are negligible. 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. See Appendix A for an example calculation. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 9 . 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.601. Minimal volume change occurs because a minimal piping deformation occurs therefore.C. 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 62-762.601. By monitoring the temperature of the contained substance in the piping during a pressure test. 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.8 as the stress in a pipe wall. the complexity of Fourier's heat transfer calculations and the need to monitor the ambient and the exterior pipe surface temperature can be eliminated. Hoop stress is defined in ASME B31. Proposed Procedure The following procedure is proposed to be conducted in association with the current API 1110 pressure testing. Barlow's Formula is the common method used to determine hoop stress in the wall of pipe.

the deviations. and the physical state of that contained substance (i. The first step is to identify known conditions and factors. then the volume of the contained substance can be calculated by using the inside diameter of the pipe.A.C. 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. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 10 . When the theoretical calculation(s) is complete.e. liquid. the theoretical calculated pressure can be determined. The next step is to gather referenced data for the known conditions and factors.C.. These include the material of which the pipe being pressure tested is constructed. Once the length is determined. This unaccounted volumetric flow can be compared to Table BPP found in Rule 62-762. Temperature of the contained substance should be monitored with the same regularity of the pressure readings.A. F. between the theoretical calculated pressure(s) and the actual measured pressure(s) should be analyzed and an unaccounted volumetric flow determined. Arthur D Bosshart II TECO Energy F. 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. 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. the contained substance within the pipe. Please see Appendix E for a field simplified field method for determining compliance. along with the compressibility of the contained substance. if present. Once the testing is completed and all data is gathered.601. This will provide an explanation for such abnormal occurrences while maintaining the accuracy of the test. solid. gas). 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. and set forth below. The pressure test should be performed in accordance with API 1110 monitoring the pressure and ambient temperature. to determine a pass or a fail.

therefore by referencing the Table BPP above it is found that an unaccounted volumetric flow of 0. Therefore. it can be o determined that the pressure test in Example #1 was a passing test assuming a 1 F temperature change occurred. 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.601. Please see Appendix E for a field simplified field method for determining compliance. It was determined that 0. However.5 gallons/hr 1 gallons/hr Testing Using a spreadsheet developed for this purpose and using data from Example #1.000 gallons. 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. F.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.A. A full set of calculations of the theoretical pressure for Example #1 is shown in Appendix A. Arthur D Bosshart II TECO Energy Frequency of Testing Line Segment Capacity Line Segment Capacity greater Line segment capacity Less than 50. 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 . there are a few scenarios that could potentially produce an inaccurate result. Neither of the two examples actually monitored the temperature of the contained substance during testing and therefore these calculated examples are demonstrative only.161469 gallons/hr were unaccounted for during this test.2 gallons/hr 0. The pipe segment tested has a capacity less than 50.C. Calculations were also conducted for Example #2 which was also determined to be a passing pressure test. 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 62-762.2 gallons/hr or less is required to be in compliance.

Arthur D Bosshart II TECO Energy is covered by shade. the proposed procedure would become too complex and could lead to a greater potential for error. Consequently. The reverse is true if the temperature measurements were recorded from the cooler half of the pipe. and heat transfer equations but. If a pipe segment is entirely exposed to direct solar radiation or only exposed to diffused and reflected solar radiation. 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. 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. such piping should be tested during early morning or twilight hours to minimize temperature gradients. where portions of piping are exposed to intense day time solar radiation. the chance for temperature gradients is minimized and testing can be conducted at anytime. ∆T = 1.5oF ∆T = 2. solar engineering equations. Calculations can be conducted from weather data. This would cause the calculations to represent that a greater volumetric loss had occurred and could possibly fail a passing test. 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. Temperature Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 12 . 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. These temperature gradients are illustrated below. If the temperature readings of the contained substance are being measured on the warmer half of the pipe.5oF ∆T = 1oF ∆T = 4oF No Direct Exposure to Solar Radiation Direct Exposure to Solar Radiation To assure accurate results. should be pressure tested separately so potential errors from temperature gradients can be avoided. where a portion of pipe greater than 10% is aboveground and the remaining portion is below ground.

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

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

Fourth Edition. Florida Administrative Code – Draft Rule – September 28. 2007 3) American Society of Mechanical Engineers (ASME) B31.8 . March 1997 2) Chapter 62-762. Arthur D Bosshart II TECO Energy Bibliography 1) API Recommended Practice 1110.2003 Gas Transmission and Distribution Piping Systems Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 15 .

) LTo = 11275.30538 (The length of pipe in inches at initial temperature) 3 3 VLo = 325581.VLo (Initial Volume @ Initial Temperature) Vp = (3. Energy is given in BTU 6) Rearranging the equation from step 5.36954953 = 17680. 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 .14*(3. 3) Mass of the pipe is calculated MP = VP*DP = 270.7674419 -volume is converted to in3 2) Volume of pipe material is calculated π = 3. 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 = 0.3125^2)* 11275.43 * 1 = 4033.3125 in.4 . the temperature change of the pipe is determined from the contained substance’s energy change by its temperature change ∆TP = Q/(MP*CpP) = 4033. The outside radius of the pipe in inches. 37884 .14 ro = 3. density is in pounds per gallon 5) Energy change of the substance from the measured temperature change is calculated Q = ML*CpL*∆TL = 9380* 0.12) = 3. Volume is in gallons. density is in pounds per gallon 4) Mass of contained substance ML = DL*VL = 6.37884 * 0.00046 * 325581.0043) – 1400 = 270.30538)*.583333333 .3953 in (Value must be converted to in ) 2 Vp = (π*ro *LTo) . Volume is in gallons. (Referenced Value.4681151 gal.4 / (17680.3953 * 1 = 149.7 * 1400 = 9380 .4681151 * 65.

The bulk modulus is the inverse of the substances compressibility.325581. if the initial volume value used in the equation is in gallons . 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 = 3.6674419 / 325581.3953)* 217500) = 93.0000078 * 11275.1 . 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 = (140.00043205 .3953 = 9.97 . 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. 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. This is the volume change with respect to the contained substance.4953 . Arthur D Bosshart II TECO Energy ∆Lp = βp* LTo *∆Tp = 0. βA = ∆V / (VLo*∆TL) = 140.1614693 gallons/hr .9.4953 .62052 = 325590. The answer is given in cubic inches 11) Using the overall change in volume. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 17 .21260126 79min /60 = 1.97 – 234) * 1400) / 217500 = -0.7674419 .3953 * 1) = 0. an adjusted thermal expansion coefficient for the substance is calculated.3166667 hr -0.∆VP = 149.14 * 3. Unaccounted volume is found by comparing the difference in pressure changes and rearranging the pressure formula.30538 * 3.PAM )*VLo/ ά = ((200.6674419 . The answer is given in gallons. 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 .1 = 140.315144785 .583333333 = 0.6674419 / (325581.03252 * 11275. The volume is given in cubic inches 9) The volume change of the pipe is calculated ∆Vp = VpT2 – VpTo = 325590.3166667 = 0. ∆VLa = (PTC . Answer is given in oF-1 12) The theoretical pressure change is calculated using the bulk modulus of elasticity of the substance.21260126 / 1.

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 #1.28 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. Data entry section of the spread sheet: Select Pipe Material Input Field Carbon Steel 0. Arthur D Bosshart II TECO Energy Appendix B The following spreadsheet was used for developing the proposed method and for calculation purposes.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 6.625 in Pipe Outside Diameter See Table on Sheet 3 0.065 in Pipe Inside Diameter See Table on Sheet 3 6.

60878 ft ∆Tp 3. Arthur D Bosshart II TECO Energy VLo = Initial Liquid Volume ∆TL = Change in Temperature βL 0.4953 in3 ∆Vp = VpT2 – VpTo ∆Vp = Change in Piping Volume ∆VP 9. piping surface area at initial temperature is used for calculation.315144785 in VpTo = πri2LTo *assuming no residual air pockets in pipe VpTo = Volume of Pipe @ Initial Temperature ri = radius of inside piping diameter ri 3.4484 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. Therefore.583333333 o F Use heat transfer Equation ∆Lp 0.62052 in VpT2 325590.1 in3 Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 19 .0000078 o F -1 LTo 11275.5581395 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.3953 in3 ∆TL 1 o F ∆VL 149.0325 in VpTo 325581.3953 in3 VpT2 = πri2LT2 VpT2 = Volume of Pipe @ Final Temperature LT2 = Length of Pipe @ Final Temperature LT2 11275. ro 3.3125 in Ape 234623.7674419 in3 232.00046 o F -1 VLo 325581.30538 in 939.

6674419 in3 Mass of Piping MP= DP*VP ML = Mass of Isolated Piping DL = Density of Piping Material VP 270.43 o F Q 4033.12 o F o ∆TP 3.36954953 lbs/gallon 1 kg/m^3 = .∆VP ∆V = Overall Change in Volume ∆V 140.0043 gallons DP 65.008345404 lbs/gallon MP 17680. 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 6.7 lbs/gallon ML 9380 lbs.37884 lbs. Energy in Substance Q=ML*CpL*∆TL Q = Heat CpL = Heat capacity of Substance BTU/lb CpL 0.4681151 gallons 1 in^3 = .583333333 F This is your results portion of the spread sheet: Unaccounted Volume ∆VLa = (PTC . Arthur D Bosshart II TECO Energy Overall Change in Volume ∆V = ∆VL .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.

No volume change occurs because no deformation of the piping material occurs.97 psi ∆VLa -0. Arthur D Bosshart II TECO Energy PTC 200.1614693 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.6 in. Therefore. 4) The radial temperature gradient of the pipe material is negligible because pipe walls are less than . 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. and during normal testing conditions an extreme temperature change will not occur over single test duration. 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. piping surface area at initial temperature is used for calculation.21260126 gallons ∆VLa /hr 0.

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.4 PSI change per unit of temperature will be known as the “P” coefficient in the pressure testing packet in appendix I.4 PSI occurs for every . This 9.1 F change in temperature within a perfectly isolated volume. 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 . 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.

4 PSI occurs for every . The Allowable Pressure Tolerance (APT) is calculated by defining an acceptable volumetric loss which for purposes of compliance in Florida is defined to be . See Equation 4. When the pressure testing is complete the magnitude factor (MF) should be multiplied by 9.2 gallons/hour (∆VLa/hr) by Table BPP within 62-762 F. liquid density. pipe heat capacity. Using the piping volume that was calculated prior to testing.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. the APT lookup table must be present. 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. piping thermal expansion. APT is the allowable pressure difference between the theoretically calculated pressure (P Tc) and the actually measured pressure (Pam). the noted temperature change o during the testing period should be divided by . Arthur D Bosshart II TECO Energy compressibility.A. Equation 1 is the formula used for calculating ATP where compressibility (ά) and piping volume at the initial temperature are shown (V Lo).C. the APT can be found using the APT lookup table.4 PSI and then added to the initially measured pressure (Pi) from the beginning of the test to determine the theoretically calculated pressure (PTc). 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. pipe density.1 F change in temperature. APT = ((∆VLa/hr)(ά))/VLo (1) APT = PTc . the lower limit of the actually measured Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 23 . liquid thermal expansion.1 F to determine the magnitude factor to be used later. PTc = Pi + 9. By subtracting the APT defined for the given piping volume from the PTc. and liquid heat capacity the “P” coefficient for any substance may be found.

39 0.19 25.72 29.12 12.2 3400 9.33 60.25 0.88 14.2 3900 8.54 0.18 16.55 49.10 33.2 2600 12.30 0.10 0.31 17.16 10.07 38.61 0.2 600 54.32 0.96 10.19 36.77 0.66 27.25 43.77 24.2 2500 13.37 11.64 28.50 0.2 1900 17.30 31. Appendix F APT Lookup Table o 9.59 31.21 36.19 0.31 54.2 1600 20.99 19.39 27.2 3800 8.77 10.94 16.91 23.89 13.89 31.50 18.2 2800 11.42 23.54 21.45 14.71 25.59 10.19 33.82 11.2 2000 16.00 18.2 3000 10.31 0.2 3200 10.08 16.50 54.98 40.37 0.48 19.2 800 40.14 77.26 15.34 0.99 20.2 3600 9.) APT (PSI) APT (PSI) APT (PSI) APT (PSI) ∆VLa /hr 500 65.2 2900 11.25 15.4 PSI / .05 0.50 0.63 0.25 87.25 hr Test Duration 1.13 0.54 20.2 1800 18.10 0.2 4100 7.2 2100 15.36 12.75 0.17 22.07 0.40 21.88 13.17 0.13 21.66 0.54 19.42 72.38 72.21 0.56 0.2 1700 19.43 59.66 39.99 38.59 16.89 28.75 22.78 54.2 2300 14.75 130.46 41.70 17.52 14.78 0.32 12.2 1100 29.2 Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 24 .2 1200 27.2 700 46.06 12.76 14.62 34.38 67.2 1300 25.10 18.19 32.50 0. If the measured pressure during the duration of a pressure test falls below this defined lower limit then the test fails.75 hr Test Duration 1 hr Test Duration 1.91 0.64 0.2 3700 8.54 18.2 900 36.84 46.13 24.83 19.18 18.31 21.2 2400 13.00 108.2 3100 10.68 93.95 15.65 15.2 1000 32.38 0.2 4300 7.65 15.73 0.63 43. Arthur D Bosshart II TECO Energy pressure can be defined.20 13.2 2200 14.75 29.2 3300 9.43 15.55 16.59 11.59 16.50 0.38 0.5 Piping Volume (Gal.59 18.03 17.05 17.60 12.2 4000 8.2 1400 23.08 15.25 0.97 81.73 20.17 0.79 15.2 3500 9.19 0.25 48.2 4200 7.14 24.61 13.75 27.2 1500 21.38 65.83 50.91 25.13 22.19 0.17 30.50 90.1 ∆ F Test Duration .75 0.15 13.25 45.64 0.00 36.11 20.61 62.17 0.75 26.63 108.2 2700 12.

75 hrs.53 8.25 hrs.88 11.08 14.89 12.50 0.67 12.2 4800 6.2 5000 6.33 13.05 0.59 0.00 20.18 0. Arthur D Bosshart II TECO Energy 4400 7. in diameter and had a schedule 40 wall thickness.2 4900 6.57 13.00 .82 14.5 hrs.41 9. Test Duration 80.2 4700 6.66 8.2 4500 7.46 11. The line was properly packed and the initial temperature and pressure readings Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 25 .88 13. Test Duration 1.00 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 Piping Volume (Gallons) Appendix H Simplified Field Method Sample Calculation For example. an underground pipe that contains #2 diesel fuel is pressure tested in the state of Florida.00 60.09 9. Test Duration Allowable Pressure Tolerance "APT" (PSI) 1 hr.94 9.10 13.36 14.2 4600 7.00 40.32 0.83 0.80 9.88 0. Test Duration 1.26 11.00 100.70 10. The volume of the pipe that is to be isolated was calculated to have a capacity of 1400 gallons.06 11.25 9.2 Appendix G Compliance Curve Compliance Curve #2 Diesel APT = ((∆VLa /hr)*ά) / VLo 120. Before the test it was determined that the pipe was 6in.00 0.

4 PSI occurs for every o .1 F . See Appendix J to view the completed Line Pressure Testing form using this example.5 hours and the final temperature and o pressure readings were 71.4 PSI – 46. Lower Limit = 203. we find that for a piping system of 1400 gallons.61 PSI = 156.1 F and 171 PSI respectively. o o o MF = (71.79 PSI The final temperature reading from the test was 171 PSI.1 F = 11 Next.61 PSI.4 PSI Using the APT lookup table. the allowable pressure tolerance (APT) is 46. The magnitude factor has no units. the lower limit for compliance is determined.4(MF) = 100 PSI + 9.1 F change in temperature within a perfectly isolated volume therefore the magnitude factor (MF) is first calculated.4 PSI(11) = 203.70 F)/. The test lasted 1. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 26 . The final reading is greater than the lower limit therefore the pressure test passes. Is the piping system in compliance? Using the simplified procedure we know that a linear pressure change of 9. PTc = Pi + 9. Arthur D Bosshart II TECO Energy o were 70 F and 100PSI respectively. Next. the theoretically calculated pressure (PTc) is determined.

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

is greater than the final pressure (PF) reading.7 of API Recommended Practice 1110 Fourth Edition. on (14) line 5? Y N Test Result If the lower limit pressure (Lower Limit). otherwise circle the compliance determination of PASS. on line 5 then circle the compliance determination of FAIL. find the associated APT value. Using the “Facility Identified Isolated Piping Segment Capacity” on line (1). 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). on line 13. 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. 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. less than the final pressure (P F) reading. 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. 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 / 0.1 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.

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.

65 15.50 0.18 16.72 29.95 15.32 0.10 33.2 3100 10.18 18.33 60.62 34.48 19.59 18.25 9.13 0.2 2600 12.2 1700 19.50 0.46 41.71 25.08 15.94 163.2 300 108.20 13.98 40.10 0.59 11.78 54.2 2700 12.03 17.75 29.38 67.5 Piping Volume (Gal.15 13.45 14.2 3700 8.75 652.4 PSI / .88 13.00 108.42 72.25 45.2 2200 14.19 32.66 39.2 2900 11.12 12.38 0.75 22.78 0.31 0.07 0.1 ∆oF Test Duration .73 0.89 28.25 0.63 108.30 31.2 1900 17.89 12.08 16.30 0.2 2300 14.2 700 46.63 43.25 0.46 11.00 36.41 9.75 0.2 3900 8.36 12.54 20.31 21.16 10.2 1400 23.2 4500 7.2 1200 27.10 18.2 2000 16.61 62.32 12.19 0.2 3400 9.14 24.2 1000 32.64 0.75 130.2 2400 13.17 22.2 2100 15.91 23.60 12.19 25.2 400 81.13 24.2 3600 9.73 20.94 16.83 0.2 3500 9.88 326.2 1800 18.39 0.96 10.2 2500 13.31 17.75 0.38 0.2 1600 20.19 0.68 93.25 15.40 21.2 200 163.89 13.82 11.54 21.05 0.05 17.56 108.50 90.25 87.2 1100 29.97 81.77 0.31 54.50 18.66 0.83 19.88 14.43 59.59 16.61 0.91 0. Arthur D Bosshart II TECO Energy APT Lookup Table #2 Diesel Fuel Oil 9.2 4000 8.18 0.17 0.2 1500 21.63 0.2 3200 10.08 14.2 4300 7.75 27.09 9.2 3800 8.) APT (PSI) APT (PSI) APT (PSI) APT (PSI) ∆VLa /hr 100 326.99 38.56 0.50 0.59 10.50 0.54 18.2 4400 7.99 20.55 49.19 0.21 0.50 0.61 13.2 500 65.55 16.17 0.25 217.13 0.52 14.17 30.11 20.25 48.2 4600 7.42 23.2 600 54.50 54.66 27.84 46.64 28.07 38.17 0.2 1300 25.50 0.13 21.89 31.2 3000 10.75 26.36 14.76 14.2 4100 7.2 2800 11.83 50.38 65.21 36.10 0.37 0.13 217.70 17.59 31.38 72.67 12.54 19.37 11.25 hr Test Duration 1.75 145.2 Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 30 .2 900 36.26 15.75 hr Test Duration 1 hr Test Duration 1.25 0.2 800 40.34 0.06 12.77 10.00 543.39 27.65 15.59 16.54 0.64 0.2 3300 9.2 4200 7.91 25.79 15.13 22.77 24.82 14.14 77.19 36.25 435.99 19.50 271.43 15.19 33.00 18.75 135.25 43.00 181.50 0.

2 6100 5.21 7.41 0.72 7.18 5.53 6.2 8100 4.13 8.35 8.13 7.80 8.24 5.2 7400 4.2 8400 3.88 5.20 0.72 7.26 0.32 0.74 0.66 6.88 8.2 6900 4.59 0.58 6.26 12.59 4.2 4900 6.30 6.63 4.2 5800 5.71 4.91 9.17 0.47 0.06 11.44 7.53 10.66 8.2 8800 3.87 6.2 9600 3.32 7.04 8.2 8500 3.2 5000 6.77 9.00 9.58 5.18 7.63 7.2 8300 3.63 5.27 8.06 6.2 7100 4.50 9.38 11.59 0.59 8.86 0.08 5.2 7600 4.00 6. Arthur D Bosshart II TECO Energy 4700 6.50 10.04 7.47 4.88 11.55 9.2 7000 4.80 0.13 5.2 9000 3.63 9.91 10.2 6600 4.40 8.82 0.68 5.89 0.52 0.15 8.2 6400 5.47 5.31 0.06 0.06 8.2 6500 5.94 0.77 9.98 7.2 6700 4.37 10.65 0.72 6.37 0.06 0.84 5.80 8.37 9.10 6.32 0.55 4.02 6.43 4.2 4800 6.55 0.45 8.66 9.16 0.63 7.49 8.54 11.65 7.22 11.25 0.33 13.93 5.40 8.83 6.55 7.97 8.12 6.53 8.2 6000 5.66 12.2 5500 5.73 5.98 5.2 Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 31 .96 0.40 4.08 0.2 7200 4.05 0.80 9.60 0.2 8600 3.93 7.51 6.73 6.24 9.53 7.94 6.2 6200 5.03 5.2 8200 3.2 5700 5.71 8.37 6.75 5.2 9100 3.18 6.71 11.87 0.2 8700 3.78 5.80 6.69 8.2 5600 5.2 7500 4.86 0.06 10.85 7.2 5100 6.70 0.2 9200 3.25 0.37 10.35 7.50 0.25 9.33 0.26 11.90 8.2 8000 4.2 7900 4.46 12.24 6.2 5300 6.2 7300 4.88 0.94 9.78 6.04 0.06 0.79 5.59 0.25 8.30 7.2 5200 6.29 5.63 10.2 7800 4.66 6.2 5400 6.10 13.88 7.11 7.2 8900 3.02 8.94 0.68 0.70 0.18 6.70 10.77 0.67 4.04 7.2 6300 5.02 0.2 5900 5.57 13.44 6.88 13.96 7.21 10.07 12.19 0.80 7.2 9300 3.40 7.16 8.91 7.94 6.36 0.2 9400 3.12 9.26 7.88 9.60 6.89 11.51 4.41 5.2 9500 3.83 7.47 7.06 10.77 10.46 0.53 5.79 0.88 0.89 6.2 6800 4.2 7700 4.09 0.25 7.35 5.45 0.

53 0.2 9900 3.49 6.33 4.59 0.00 0.26 4.66 0.55 6.2 Compliance Curve #2 Diesel APT = ((∆VLa /hr)*ά) / VLo 120.35 5.2 9800 3. Test Duration 80.36 4.00 100.00 60.00 20.30 4.75 hrs.00 .73 0. Test Duration 1.00 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 . Test Duration 1.39 5. Arthur D Bosshart II TECO Energy 9700 3.48 5.2 10000 3.5 hrs. Test Duration Allowable Pressure Tolerance "APT" (PSI) 1 hr.00 40.44 5.44 6.25 hrs.61 6.

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 .

37884 lbs. Subtracts the outside volume if pipe was a solid cylinder from the inside capacity of the pipe.1 F change in temperature within a perfectly isolated volume. Answer must be given in gallons. Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 34 . must be in pounds per gallon) VP = 270.4681151 gal.14 ro = 3. Must be in gallons) ML = DL*VL = 6.00046 * 325581. o -1 o -1 βL = . This calculation is independent of the amount of volume but requires an initial value for volume to begin the calculation of the “P” coefficient.00046 F (Referenced coefficient.0043) – 1400 = 270.14*(3.4 PSI occurs for every .3953 * . For #2 Diesel it is found that a linear pressure change of 9.1 F) 3 ∆VL = βL*VLo*∆TL = 0.3953 in (Value must be converted to in ) o o ∆TL = Tf – Ti = . must be in F ) 3 3 VLo = 325581. DP = 65. The outside radius of the pipe in inches./gal (Referenced Coefficient. pipe. We are using a 6 in.97674419 in 2) Volume of pipe material is calculated 3 This is not the capacity of the pipe. we will use the capacity of one of our actual piping systems. (Referenced Value./gal (Referenced Coefficient. 3) Mass of the pipe is calculated The mass must be calculated to determine energy transfer.30538 (The length of pipe in inches at initial temperature) 3 3 VLo = 325581. π = 3.) LTo = 11275. must be in pounds per gallon) VLo = 1400 gal. 4) Mass of contained substance This is calculated to determine energy transfer.1 = 14.4681151 * 65.36954953 = 17680.7 lbs. (Initial volume @ the initial temperature.1 F.3125 in. (From Equation 2) MP = VP*DP = 270.1 F (Define your temperature change as .7 * 1400 = 9380 lbs.36954953 lbs.3125^2)* 11275.3953 in (Value must be converted to in ) 2 Vp = (π*ro *LTo) .VLo (Initial Volume @ Initial Temperature) Vp = (3.4681151 gal. In the example below. 1) Volumetric Thermal Expansion of Liquid (#2 Diesel Fuel) This is the change in volume due to the change in temperature. DL = 6.30538)*. 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 . 5) Energy change of the substance from the measured temperature change is calculated. This is the amount of piping material in in .

12) = . (From Equation 3) o ∆TP = Q/(MP*CpP) = 403. (From Equation 7) 2* + 2 3 VpT2 = π*ri (LTo ∆Lp) = 3. 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. 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.315144785) = 325582.) LTo = 11275. F (Referenced Coefficient. Q = 403.0000078 F (Referenced coefficient.1 F) Q = ML*CpL*∆TL = 9380* 0.30538 + .3053 in 9) The volume change of the pipe is calculated This is the volume change of the pipe due to thermal expansion. π = 3. The differences from material to material are negligible.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.3953 = 0.0325 * (11275.30538 (The length of pipe in inches at initial temperature) ∆Lp = 0. Must be in “BTU/lb. (Referenced Value.3583333333 = 0. o -1 o -1 βp = .37884 * 0.37884 lbs.325581.0000078 * 11275. Must be in “BTU/lb. F”) MP = 17680.14 * 3.91 in (From Equation 9) Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 35 .1 = 403.3583333333 F (From Equation 6) ∆Lp = βp* LTo *∆Tp = 0.91 in 10) The overall change in volume accounts for the expansion rates of the substance and the pipe.43 * .0325 in.97674419 in (From Equation 1) 3 ∆VP = . (From Equation 4) o o CpL = .3953 in (Value must be converted to in ) 3 ∆Vp = VpT2 – VLo = 325582.34 BTU 6) Temperature Change of Piping Material Rearranging the equation from step 5. ML = 9380 lbs.30538 in. F”) o o ∆TL = Tf – Ti = .14 ri = 3.0315144785 in.34 BTU (From Equation 6) o o CpP = .3053 . the temperature change of the pipe is determined from the contained substance’s energy change by its temperature change.34 / (17680.043 BTU/lb. The inside radius of the pipe in inches. 3 ∆VL = 14.3053 in (From Equation 8) 3 3 VLo = 325581. must be in F ) LTo = 11275.30538 * . F (Referenced Coefficient. (The length of pipe in inches at initial temperature) o ∆Tp = .12 BTU/lb.1 F (Define your temperature change as . 3 VpT2 = 325582.0315144785 in.

given in hours) APT = (((∆VLa/hr)(ά))/VLo)*t = ((0.91 = 14.3953) * 217500) = 9.06674419 in (From Equation 11) 3 3 VL0 = 325581. Compressibility must be in psi) “P” coefficient = ∆P = (∆V/VL0) / ά = (14.3953 in (Value must be converted to in ) ά = 217500 psi (Referenced Coefficient.∆VP = 14. 3 ∆V = 14.397 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 .97674419 . between the theoretically calculated pressure (PTc) and the actually measured pressure (Pam). The equation below can be arranged to use compressibility or the bulk modulus of elasticity.2 * 217500)/1400)*1. The bulk modulus is the inverse of the substances compressibility.5 = 46. (Duration of test.2 gallons/hour (∆V La/hr) by Table BPP within 62-762 F.2 gal/hr (This is the minimal accepted leak rate defined by environmental authority) ά = 217500 psi (Compressibility of #2 Diesel) VLo = 1400 gal. Arthur D Bosshart II TECO Energy 3 ∆V = ∆VL . defined by an environmental authority.06674419 in 12) Determination of the “P” Coefficient.06674419 / 325581.A. 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 theoretical pressure change is calculated using the bulk modulus of elasticity of the substance.C. We will use the referenced and calculated values from Appendix K.0. APT is the allowable pressure difference.61 psi Effects of Temperature Change on Pressure Testing and Maintaining Environmental Compliance 36 .5 hrs. (Value must be in Gallons) t = 1. 1) APT = (((∆VLa/hr)(ά))/VLo)*t ∆VLa/hr = 0.