This document is not an API Standard; it is under consideration within an API technical committee but has not received all approvals
required to become an API Standard. It shall not be reproduced or circulated or quoted, in whole or in part, outside of API committee
activities except with the approval of the Chairman of the committee having jurisdiction and staff of the API Standards Dept. Copyright
API. All rights reserved.
Manual of Petroleum
Measurement Standards
Chapter 12 — Calculation of Petroleum
Quantities
Section 1 — Calculation of Static Petroleum Quantities
Part 2 — Calculation Procedures for Tank Cars
SECOND EDITION, XXXX, 2016
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
Introduction
This Chapter of the Manual of Petroleum Measurement Standards describes the standardized method for
calculating target loading quantities and actual loaded quantities of liquids in tank cars. Also addressed
within this chapter is an explanation of the factors required for the calculations.
1
Chapter 12 — Calculation of Petroleum Quantities
Section 1 — Calculation of Static Petroleum Quantities
Part 2 — Calculation Procedures for Tank Cars
1. Scope
This Chapter is applicable to all crude oils, petroleum products, and petrochemicals (including LPGs and other
liquefied gases) transported by rail tank car. It does not cover any products loaded or measured as solids. It
defines the terms required to understand the calculations, and provides instructions for their use. The cars are
assumed to be on level ground.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references,
only edition cited applies. For undated references, the latest edition of the referenced document applies (including
any addenda / errata).
API Manual of Petroleum Measurement Standards (MPMS) Chapter 1, Vocabulary
API Manual of Petroleum Measurement Standards (MPMS) Chapter 3.2, Tank Car Measurement
API Manual of Petroleum Measurement Standards (MPMS) Chapter 10, Sediment and Water
API Manual of Petroleum Measurement Standards (MPMS) Chapter 11.2.4, Temperature Correction for the
Volume of NGL and LPG, Tables 23E, 24E, 53E, 54E, 59E, and 60E
API Manual of Petroleum Measurement Standards (MPMS) Chapter 11.2.5, A Simplified Vapor Pressure
Correlation for Commercial NGLs
API Manual of Petroleum Measurement Standards (MPMS) Chapter 12.2, Calculation of Petroleum Quantities
Using Dynamic Measurement Methods and Volumetric Correction Factors
ASTM D15551, Standard Test Method for Calculation of Volume and Weight of Industrial Aromatic
Hydrocarbons and Cyclohexane
3. Terms, Definitions, Acronyms, and Abbreviations
For the purposes of this document, the following terms and definitions apply. Terms of more general use (i.e.,
API Gravity, Density, etc.) may be found in API MPMS Chapter 1.
3.1
General
3.1.1
capacity table adjustment factor
CTAF
Correction applied to capacity table volumes.
3.1.2
closed loading/unloading
The manway remains closed or covered during loading/unloading.
3.1.3
compartment car
A car with two or more independent (no common walls) tanks, each with its own manway, reference point, and
capacity table.
1
2
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
3.1.4
correction, pressure, liquid
CPL
Correction for the compressibility effect of pressure on a liquid.
3.1.5
correction, pressure, shell
CPS
Correction factor for the effect of pressure on a steel container.
3.1.6
correction, sediment & water
CSW
Corrects a volume, usually at standard temperature, for the effects of suspended sediment and water (S&W)
3.1.7
correction, temperature, liquid
CTL
Compensates for the effect of temperature on a liquid.
3.1.8
correction, temperature, shell
CTSh
The correction factor for the effect of the temperature, both ambient and liquid, on the shell of the tank.
3.1.9
custody transfer measurement
The measurements specific to a change in ownership and/or a change in responsibility for commodities.
3.1.10
DOT filling limit
The minimum outage (vapor) volume required at statutory temperature, expressed as percentage of the total
capacity of a tank car, required by DOT regulations (49 CFR 173.24b or 173.314 as of this printing).
3.1.11
funnel flow cars
Tank cars that have a slight “V” shape to allow drainage.
3.1.12
general purpose tank car
A non-pressure tank car designed and constructed under DOT regulations to transport liquids of relatively low
volatility, such as asphalts, crude oils, fuel oils, solvents, specialty chemicals, etc.
3.1.13
gross observed volume
GOV
The total observe volume (TOV) of all petroleum or chemical liquids and sediment and water (S&W), excluding
free water (FW), at observed temperature and pressure.
3.1.14
gross standard volume
GSV
The gross volume (GV) or gross observed volume (GOV) corrected to base temperature and pressure conditions.
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
3
3.1.15
heel
The amount of product liquid and vapor present in a car before loading, or left in a car after unloading.
3.1.16
innage gauge
The depth of liquid in a tank measured from the datum plate or tank bottom up to the surface of the liquid.
3.1.17
interior lining
The surface coating applied to the interior of a tank car shell to prevent the contents from contacting the metal
shell.
3.1.18
light weight
tare
The number painted on the sides of a [rail] tank car near its ends indicating the empty weight of the car.
3.1.19
liquefied gas
A generic term referring to gases (such as ammonia, butylene, propylene, ethylene oxide, propylene oxide, etc.)
stored and transported under pressure as a liquid.
3.1.20
liquefied petroleum gas
LPG
A hydrocarbon gas maintained in a liquid state.
3.1.21
liquid equivalent
The quantity of liquid product contained as a gas in the vapor space above the liquid surface in a pressure
container.
3.1.22
[weight] load limit
The number on the sides of a rail tank car near its ends indicating the maximum legal weight of its contents.
3.1.23
magnetic float gauge
A gauging device employing a floating magnet to permit measuring the liquid level in a container without
opening the container to the atmosphere.
3.1.24
manway [nozzle]
A cylindrical opening on the top of a [rail] tank car with a hatch for [personnel] access to the interior of the car.
3.1.25
manway nozzle height
The vertical distance downward from the top lip of the nozzle (hatch open) to the inside top of the car shell,
measured at the point on the rim closest to the center of the car.
4
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
3.1.26
maximum fraction of liquid allowed
MFLA
The DOT filling limit, expressed as a decimal fraction, of the maximum volume of liquid allowed at statutory
temperature.
3.1.27
maximum fraction of liquid loaded
MFLL
The volume of liquid actually loaded, expressed as a decimal fraction, at statutory temperature.
3.1.28
net standard volume
NSV
The gross standard volume (GSV) corrected to exclude non-merchantable components such as sediment and
water (S&W).
3.1.29
NIST traceable
A property of a measurement result whereby the result can be traced back to NIST by an unbroken chain of
calibrations.
3.1.30
open loading / unloading
For a general purpose tank car, the manway hatch remains open during loading/unloading, thus sampling and
temperature and level measurements generally take place through the open manway.
3.1.31
[outage] gauge
The measure of the liquid level in a tank, vertically from the [rail] tank car’s reference gauge point.
3.1.32
pressure tank car
A closed tank car (no direct access to the interior of the car for measurement) designed and constructed under
DOT regulations to transport high volatility products and liquefied compressed gases under pressure (typically
100-200 psig for LPG).
3.1.33
reference conditions
The specific physical conditions for comparison of measurements taken at other physical conditions.
3.1.34
reference pressure
The specific pressure for comparison of measurements taken at other pressures.
3.1.35
reference temperature
standard temperature
The specific temperature for comparison of measurements taken at other temperatures.
3.1.36
slip tube
A graduated hollow rod used for measuring liquid outages in a pressure car.
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
5
3.1.37
statutory outage
The percentage of the total liquid capacity of a tank car reserved for vapor space set by DOT 49 CFR 173.24b or
173.314 (as of this printing) for calculating loading target outage.
3.1.38
statutory temperature
Tstat
The temperature set by DOT 49 CFR 173.24b or 173.314 (as of this printing) for calculating loading target
outage.
3.1.39
table max volume
Vtblmax
The greatest volume in a capacity table.
3.1.40
tank car capacity
stenciled capacity
stenciled volume
Vs
The number painted onto the ends of a [rail] tank car indicating its shell-full capacity.
3.1.41
tank capacity table
Table showing the liquid volume capacities, on an innage or ullage (outage) basis, or the corresponding vapor
space capacities, in a tank, tank car or vessel compartment, at various liquid levels, which are measured at the
reference gauge point: from the datum up to the liquid surface level for innage gauges; or, from the reference
gauge point down to the liquid surface level for ullage (outage) gauges.
3.1.42
tank car reference gauge point
The point at the top edge of the manway opening along the longitudinal centerline closest to the midpoint of the
tank car from which all liquid level measurements shall be taken.
3.1.43
tank car shell-full
The liquid volume at the transition point where air or vapor first becomes entrapped in a location that is not in
direct communication with the manway.
3.1.44
tank gauging
A process for determining the height of liquid in a tank or container by measuring the vertical distance from the
bottom or fixed datum up to the liquid surface level when using innage gauging, or by measuring the vertical
distance from the reference gauge point down to the liquid surface level when using ullage (outage) gauging.
3.1.45
thermometer well for tank cars
thermowell
A metal tube, sealed at the bottom, which extends into tank cars requiring closed loading / unloading.
6
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
3.1.46
total observed volume table
TOVtbl
The total measured volume of all petroleum liquids, sediment and water (S&W), and free water (FW) at observed
temperature and pressure.
3.1.47
two percent marker
2% marker
A metal liquid level indicator installed in tank cars, usually at the level where the car is filled to 98% of capacity,
but occasionally at other levels.
3.1.48
vapor space
The volume above the liquid surface.
3.2 Acronyms and Abbreviations
For the purposes of this document, the following acronyms and abbreviations apply.
CPL
correction, pressure, liquid
CPS
correction, pressure, shell
CSW
correction, sediment & water
CTAF
capacity table adjustment factor
CTL
correction, temperature, liquid
CTSh
correction, temperature, shell
DOT
Department of Transportation
FW
free water
GOV
gross observed volume
GOVtbl
table gross observed volume
GSV
gross standard volume
GV
gross volume
LPG
liquefied petroleum gas
MFLA
maximum fraction of liquid allowed
MFLL
maximum fraction of liquid loaded
NSV
net standard volume
NIST
National Institute of Standards and Technology, formerly the National Bureau of Standards
(NBS)
S&W
suspended sediment and water
Vs:
stenciled volume
Vtblmax
the greatest volume in a capacity table
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
7
4. Required Data Acquisition
4.1 General
As with any calculation, the results are only as reliable as the data entered. It is essential that the tank car
information and measurements be NIST traceable and as accurate as possible. Temperature and level
measurement equipment and procedures should also be reviewed for compliance with API custody transfer
standards (see API MPMS Chapter 3.2).
4.2 Tank Car Data
4.2.1 General
Experience has shown that inaccurate tank car information is often used (sometimes for many years). Data
obtained off the tank car should be verified to be identical to that in any industry or company data bases used.
4.2.2 Light Weight
Obtained from the side of the car or industry database.
4.2.3 Load Limit
Obtained from the side of the car or industry database.
4.2.4 Stenciled Volume
Obtained from either end of the car or industry database. This is the amount of water in gallons and liters that the
car contains at the shell-full point. For funnel flow cars, the shell-full point is at the center of the car (there will be
air pockets on both sides where the liquid cannot reach), but pressure cars, which are horizontal cylinders, will
include the manway volume. The stenciled volume is determined directly by metering water into the car or indirectly
by strapping the car. If an interior lining is removed, replaced, or added at a later date, the stenciled volume should
be redetermined.
4.2.5 Tank Car Capacity Table
Obtained from the tank car owner, manufacturer, or industry database. Care must be taken to ensure that the
correct capacity table is used (it is not uncommon for individual locations to have outdated or wrong tables). A
car’s useful statutory life is 50 years, so there may be several different versions in use for the same car.
Furthermore, as of this writing there is no industry standard format, and a manufacturer may have changed their
format several times over the years. Thus, it is generally impossible to determine by observation when the table
was issued and therefore whether it is more current than another table. If in doubt, contact the owner of the tank
car.
The table may be based on either innage or outage gauges and may indicate either liquid or vapor space gallons.
These are referred to as Outage Liquid, Outage Vapor, Innage Liquid, or Innage Vapor tables. Care must also be
taken to ensure that the capacity table is used properly. There may also be no indication as to what type of table it
is, and thus the table may be used incorrectly. The manufacturers have developed these tables using the inside top
of the shell at the center of the car, the rail car shell-full point, as a reference point. Distance increments
(normally ¼ in.) are then listed from the reference point down to the liquid surface (outage) or from the bottom of
the car directly below the reference point to the liquid surface (innage), and the corresponding liquid or vapor
volume is calculated and inserted in the table. Using an Innage Liquid table as an Outage Vapor table (or vice
versa) for a funnel flow car will introduce an error on the order of several hundred gallons as the tables are not
symmetrical. Experience has shown that table misinterpretation is the most common cause of calculation error.
The same capacity table may be assigned to hundreds of dimensionally similar, but not identical, tank cars. Tank
cars cannot be constructed to exactly match the table, but the table may be mathematically sized to each tank car by
applying the capacity table adjustment factor (CTAF), calculated by dividing the stenciled volume (Vs) by the table
max volume (Vtblmax), to every gauge volume coming out of or calculated volume going into the table.
4.2.6 Manway Nozzle Height
Liquid levels are most commonly determined via outage measurements, especially if the product is hot and
solidifies at ambient temperature. In practice, it is difficult if not impossible to take an outage measurement from
8
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
the inside top of shell reference point unless a proper measuring device (commercially available) is at hand.
Absent such a device, it is much easier to measure from the top of the open manway nozzle nearest the center
point of the car. This requires measurement of the offset between the rail car reference gauge point and the shellfull point, which in most case will be the manway nozzle height. This offset must be measured with the proper
instrument (also commercially available) for maximum accuracy. Absent a proper device, numerous “work
arounds” (usually containing systematic errors) have been developed in the field to compensate. A manway may
be ground flush with the shell at the weld, however many manways penetrate the tank car’s shell by varying
depths, as much as 3 inches. This penetration is not part of the manway’s height and should not be included.
Some tank cars may already have their original tables changed to incorporate the manway height at the request of
the car's owner. Pressure cars have a secured hatch that usually contains thermowells, magnetic float gauges, and
loading valves permanently installed. The manway height is incorporated in the magnetic float gauge rod.
4.3 Product Data
4.3.1 Traceability
All measurements must be traceable to NIST reference standards. A primary standard (1st generation standard)
may be purchased from the NIST. Due to their expense, these are normally purchased by manufacturers who use
them to verify the accuracy of the standards that they make (2nd generation). These less expensive standards are
purchased by the industry for use as field standards, which are then used to verify the accuracy of the actual
equipment used in the field (3rd generation). This 3rd generation field equipment may not be used to verify
other field equipment. The verification of the field equipment must be performed (and documented) periodically
as required by the applicable API standards.
4.3.2 Actual Liquid Temperature
Once the car is loaded, a temperature must be taken from the center of the product at the time of gauging (after
motion ceases). For very hot products like asphalt, sulfur, etc., the temperature and gauge should be taken as soon
as possible, as the product will quickly stratify, forming a nonlinear temperature gradient. For a pressure car,
sampling and measurement must be accomplished via permanently installed thermowell. The thermowell may be
filled with a heat-transferring liquid of low volatility and freeze point (usually ethylene glycol) which transmits the
temperature of the tank car contents to a thermometer or thermoprobe lowered into the thermowell.
4.3.3 Liquid CTL Table
An accurate CTL table or implementation procedure must be available to properly convert GOV to GSV and NSV
(or the reverse). It may be an industry accepted version developed by the API or ASTM or a private version
developed directly from density data, and will have a value of 1.00000 at reference temperature. Occasionally, a
product’s composition may fluctuate (or have changed) enough to justify the preparation of a new table. It is
critical that a product be properly sampled and stored to ensure that a sample representative of normal production
be available for density measurement at different temperatures. These densities can then be converted to a CTL
table via methods described elsewhere (API MPMS Chapter 11.1, for example). Multiplying a liquid’s volume by
a CTL computes its volume at reference temperature.
4.3.4 Liquid Density at Reference Temperature
The liquid’s density may be directly measured at ambient temperature and corrected to reference temperature. It is
commonly measured in grams per cubic centimeter (g/cc), kilograms per cubic meter (kg/m3), API gravity, or
specific gravity and converted to pounds per gallon (lb/gal) in vacuo. To convert density to weight in air, API
MPMS Chapter 11.5 should be used.
4.3.5 Actual Liquid Pressure
If a car is loaded with a liquefied gas, the car’s pressure has to be taken and recorded.
4.3.6 Liquid CPL Table
Liquefied gases are kept at or above their equilibrium vapor pressure and require an accurate CPL table or
implementation procedure to properly convert GOV to NSV. The table may be an industry accepted version
developed by the API, ASTM, or GPA or a private version developed directly from density/pressure
measurements.
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
9
4.3.7 Sediment & Water
If a car is loaded with crude oil, sediment and water should be determined via API MPMS Chapter 10.
4.3.8 Liquid Gauge
4.3.8.1 General Purpose Cars
Once the car is loaded, a gauge must be taken at the reference gauge point. The reference gauge point is now
defined (API MPMS Chapter 3.2) as being at the top edge of the manway opening at the longitudinal centerline of
the tank car at the point on the manway circumference closest to the midpoint of the tank car. Most outage capacity
tables are referenced to the shell-full point, so an outage gauge whose zero point is at the manway rim will need the
manway height subtracted before entry into the capacity table. An outage measurement from an instrument with
zero point at the shell-full point needs no such correction. Liquid level measurement should be made at the same
time an actual liquid temperature is recorded. The contents must be allowed to cease motion (some products may
take as much as 15 minutes) before the gauge is taken, as any wave motion will result in an artificially low outage
(or high innage) and thus the volume of liquid calculated will be overstated. The gauge may be taken:
(a) as an outage gauge from the top of the manway nozzle,
(b) as an outage gauge from the inside top of the shell, or
(c) as an innage gauge.
Two percent markers are not accurate or traceable measurement devices, and are not recommended for custody
transfer measurements. If applicable, free water (FW) should also be gauged.
4.3.8.2 Pressure Cars
Gauges are taken from an installed magnetic float gauge (slip tubes have been phased out due to emission
concerns). These are outage gauges normally referenced to the top inside of the shell, so manway heights are not
required. The device consists of a spherical toroidal float with interior magnets that moves up and down around a
hollow tube (sealed to the outside) as the car’s liquid level changes. Another magnet is attached to the bottom of a
graduated gauge rod located in the hollow tube and accessible from the outside. When the gauge rod is manually
pulled up until the two magnets link, the liquid level’s outage may be read off the rod. The gauge will only indicate
outages for the upper third of the car and cannot indicate the presence of liquid below it.
Magnetic float gauge tubes should not contain so much antifreeze or similar type liquid (to prevent condensed
water from freezing) as to wet the visible portion of the rod. If a tube is filled with such liquid, its buoyant force
on the rod will make the gauge float higher and overstate the product level.
The contents must be allowed to cease motion (some products may take as much as 15 minutes) before the gauge
is taken, as any wave motion will result in an artificially low outage (or high innage) and thus the volume of
liquid calculated will be overstated.
An outage offset may have to be calculated if the gauge’s reference relative density (specific gravity) is different
from that of the product to be measured, or if the temperature of the liquid differs substantially from reference
temperature. A more dense liquid will cause the float to float higher and result in a smaller outage reading, thus
indicating that there is more liquid in the car than is really there. A less dense liquid will have the opposite effect,
the gauge indicating that there is less liquid than is really there. Temperature has a similar effect. Temperatures
higher than reference temperature will make the liquid less dense, resulting in a larger outage as the float will float
lower, so the gauge will understate the car’s contents. Temperatures less than reference temperature will have the
opposite effect. The magnitude of the effect depends on the characteristics of the gauge and the magnitude of the
change in relative density and temperature. Generally, calculations (see examples in Appendix D) show the gauge
offset may vary from < 1/8 inch to > 3 inches, depending on specific gravity and temperature changes. Successful
calculation of this effect requires knowledge of the gauge component specifications (volume of float, weight of
float and rod assembly, reference relative density) which are available from the manufacturer. See Appendix D for
the equations required and their derivations.
4.3.9 Tank Car Temperatures
A volume correction may be made for tank car shell expansion or contraction if its temperature is high or low
enough to have a significant effect. Use of this correction is optional; therefore the determination of what is
10
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
considered a “significant effect” is left to the user (Table B-1 shows a 0.1% volume increase at 114F and a 0.2%
increase at 157F). For tank cars, shell temperature is equivalent to liquid temperature. When loading very hot
material like asphalt (300 to 350°F) into an ambient tank car, it cannot be assumed that the shell temperature is the
same as the liquid temperature. Measurements have shown that products with melting points higher than the
ambient temperature will solidify and effectively insulate the shell from the bulk of the cargo. Furthermore, the
product will form a nonlinear temperature gradient fairly quickly. (Measurement of a 55°F ambient asphalt car
[unpublished data] one-half hour after loading at 307°F and showed a temperature of 304°F near the middle of the
car, 283°F one foot lower, 183°F just above the solidified asphalt on the shell, and 140°F an inch or two into the
“rind.”) Thus, a shell expansion correction should be made only when one can be sure of the shell temperature;
normally this will only occur when there is no solidified material on the shell (Appendix B and Table B-1). Cars
that have been steamed to melt the contents will also meet this criteria, and the temperature will be high enough to
have a significant effect on the volume.
4.3.10 Tank Car Pressure
A volume correction may be made for tank car shell expansion if its pressure is high enough to have a significant
effect (Annex C).
5 Actual Loaded Quantity Calculations
5.1 General
Once a tank car is loaded and the actual liquid gauge and loading temperature have been taken as indicated in
Sections 4.3.8 and 4.3.9, calculation of the net standard volume and liquid weight is relatively straightforward.
The general equations for product gross standard volume (GSV), net standard volume (NSV), and product weight
(W) are:
GSV = (TOVtbl) (CTAF) (CTL) (CTS) (CPL) (CPS)
(1)
NSV = (GSV) (CSW) = (TOVtbl) (CTAF) (CTL) (CTS) (CPL) (CPS) (CSW)
(2)
W = (NSV) (dref)
(3)
5.2 General Purpose Cars
To calculate product NSV, look up the gauge in the tank capacity table, interpolating if necessary, to find the
corresponding table total observed volume (TOVtbl). If free water is present, the volume of the free water (FW)
corresponding to its depth should be subtracted from the total observed volume to obtain the product table gross
observed volume (GOVtbl).
GOVtbl = TOVtbl - FW
(4)
This is then substituted for TOVtbl in equations (1) and (2) to obtain GSV, NSV, and W for just the product
present.
Multiply this volume first by the capacity table adjustment factor (CTAF = Vs / Vtblmax), then by the CTL at
loading temperature and the correction for the temperature of the steel shell (CTS) if desired (although CTS is
optional, it should not be used here unless it has been used in the Target calculations (Appendix A)). As general
purpose cars are not under pressure, CPL and CPS both equal 1.00000. Finally, multiply by the correction for
sediment and water (CSW), if applicable. As discussed in API MPMS Chapter 12.1.1 (refer to API MPMS
Chapter 10 for S&W%):
CSW = (100 – S&W%) / 100
For most refined products, CSW = 1 (no suspended sediment and water) and thus GSV = NSV. Equation 2 thus
becomes Equation 5.
NSV =(GOVtbl) (CTAF) (CTL) (CTS) (1) (1) (1) = (GOVtbl) (CTAF) (CTL) (CTS)
(5)
5.3 Pressure Cars
To calculate product NSV, look up the gauge in the tank car capacity table, interpolating if necessary, to find the
corresponding table gross observed volume (TOVtbl). Free water should not be present in a liquefied gas, and in
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
11
any case is not measureable in a pressure car. Multiply this volume first by the capacity table adjustment factor
(CTAF = Vs / Vtblmax), then by the CTL at loading temperature and the correction for the temperature of the steel
shell (CTS) if desired (although CTS is optional, it should not be used here unless it has been used in the Target
calculations (Appendix A)). As a rule, the final loaded pressure will be at equilibrium vapor pressure for nearly
pure product and CPL will equal 1.00000. If the pressure is higher than equilibrium vapor pressure, lighter
products or inert gases may be present (either inadvertently or by design) and CPL may be calculated for the
pressure difference, but will probably have an insignificant effect. Multiply by the correction for pressure
expansion of the steel shell (CPS), if desired (although CPS is optional, it should not be used here unless it has
been used in the Target calculations (Appendix A)). Finally, multiply by the correction for sediment and water
(CSW), if applicable. For most refined products, CSW = 1 and thus GSV = NSV. Equation 2 thus becomes
Equation 6.
NSV = (GOVtbl) (CTAF) (CTL) (CTS) (1) (CPS) (1) = (GOVtbl) (CTAF) (CTL) (CTS) (CPS)
(6)
5.4 Vapor Space Heel
Assuming no “noncompressible” or foreign gas has been introduced to offload product, liquefied gases and
liquids of sufficiently high vapor pressure will also occupy the vapor phase above the liquid. While this may be
insignificant when the vapor phase is a small percentage of the total volume of the car, it is a significant portion of
the total product after the car has been emptied. It may be calculated (based on temperature, pressure, relative
density, and composition) in liquid equivalent net gallons via GPA 8195 or any other acceptable procedure, or
fixed by mutual agreement. For a loaded car, this can be added to the net liquid gallons; for an unloaded car, this
may be subtracted from the net liquid gallons as a vapor heel.
5.5 Overload check
A car may not be overloaded by either weight or volume. The actual loaded weight should be calculated via
Equation 3 with the assumption that any free water and S&W are product, and compared to the Load Limit to
assure the car is not overloaded by weight.
The actual loaded volume should be calculated at the statutory temperature to make sure the outage volume
(vapor space left for liquid expansion) is not less than the statutory outage volume. This is done by calculating net
standard volume (Equation 6) of the total liquid in the car (use CTS and CPS only if used above) and then
dividing by the CTLstat (use CTSstat and CPSstat only if CTS and CPS are used above) at statutory temperature to
obtain the statutory liquid volume Vstat.
Vstat =
(GOVtbl) (CTAF) (CTL) (CTS) (CPS)
(CTLstat) (CTSstat) (CPSstat)
(7)
The loaded volume at statutory temperature is then divided by the stenciled volume (Vs) to obtain the maximum
fraction of liquid loaded (MFLL) at statutory temperature. This number should be equal to or less than the
product’s statutory MFLA (see Appendix A).
MFLL = Vstat
Vs
(8)
The MFLL can also be expressed as the loaded vapor space percent at statutory temperature for comparison to the
DOT filling limits.
Vapor Space % = 100 – MFLL * 100
(9)
6 Rounding
6.1 Data Level
The number of decimal places used is influenced by the source of the data. If a tank car’s capacity tables are in
whole gallons, then all subsequent gallon values should be recorded accordingly. In those cases where there are
no other limiting factors, the operator should be guided by Table 1.
12
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
6.2 Rounding of Numbers
Calculations shall be performed with no intermediate rounding. When a calculation result is to be rounded to a
specific number of decimals, it shall always be rounded off in one step to the number of figures to be recorded,
and not rounded in two or more successive steps. When the figure to the right of the last place to be retained is
less than 5, the figure in the last place retained should be unchanged.
Table 1 — Significant Digits
Units
Gallons
Pounds
Liters
Kilograms
API Gravity @ 60°F
Density pounds per gallon
Relative density
Temperature °F
Temperature °C
CTAF
CTL
CTS
CPL
CPS
No. of Decimals
xxxxx.xx
xxx.0
xxx.0
xxx.0
xxx.x
xx.xxx
x.xxxx
xxx.x
xxx.x5
x.xxxxxx
x.xxxxx
x.xxxxx
x.xxxxx
x.xxxxx
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
13
Annex A
(normative)
Loading Target Quantity Calculations
A.1
General
In order to maximize delivered quantities and minimize shipping costs, most tank cars are loaded to the maximum
amount allowable. DOT regulations, railroad regulations, manufacturing standards, and company policies govern
the maximum amount of material that a tank car may contain. DOT 49 CFR 179.13 (as of this printing) stipulates
that no tank car used for transportation of hazardous materials and its contents may weigh more than 263,000
pounds gross weight (or 286,000 lbs with special routing) or exceed 34,500 gallons capacity; however, individual
tank car construction specifications may require a smaller total weight (for example, the total weight may be
limited by the size of the truck assembly).
A.2
Required Data — Target Liquid Temperature
A.2.1 General
In addition to the requirements stated above, the following information is necessary to properly calculate target
quantities:
A.2.2 Cool Loading (Below Statutory Loading Temperature)
DOT 49 CFR 173.24b stipulates (as of this printing) that for most hazardous materials a minimum expansion
volume (vapor space) equivalent to 1% at the statutory temperature of 115°F (for uninsulated cars), 110°F (for
thermally protected cars), or 105°F (for insulated cars) must be maintained. For materials deemed poisonous by
inhalation (ethylene oxide, ammonia, chlorine, phosgene, allyl alcohol, bromine, hydrogen fluoride, etc.), the
vapor space must be 5%. During the winter (November 1 through March 31), the statutory temperatures of 100°F,
90°F, and 85°F may be used for certain liquefied petroleum gases (LPGs, butanes, propylene, etc.) and ammonia
(DOT 49 CFR 173.314). Tank cars loaded to winter limits must be shipped directly and not be stored in transit.
They must be unloaded as soon as possible after March. Liquids expand as their temperature increases and
contract as it decreases. Since the liquids will rarely be loaded at either 115°F, 110°F, or 105°F, the volume
actually loaded at loading temperature must expand to no more than 99% (or 95% for materials deemed poisonous
by inhalation) of the tank car’s capacity at the applicable statutory temperature. Thus, the lower the loading
temperature the smaller the volume that can be legally loaded. Accurate liquid loading temperatures are therefore
required both to optimize the amount loaded and avoid overloading. If the actual loading temperature is lower
than that used for target calculations, the calculated target volume will be too high and the car will be overloaded.
Conversely, if the actual loading temperature is higher than that used for target calculations, the calculated target
volume will be too low and the car will be underloaded. Accurate loading temperatures are rarely obtained from
the storage tank or loading line, especially when there is a large difference between liquid temperature and
ambient temperature. The most accurate loading temperature can be obtained by measuring the liquid in the car
during loading while the car is about two-thirds full. The final loading target outage can then be determined from
this temperature.
A.2.3 Hot Loading (above statutory loading temperature)
There are currently no DOT regulations regarding vapor space volumes for liquids loaded at temperatures above
the statutory loading temperatures. Since these liquids will cool (and may solidify) during transport, they will
normally be reheated via the tank car’s steam coils. This may cause the liquid to be heated to a higher temperature
than that at which it was loaded, thus expanding to a volume greater than that loaded and possibly overflowing the
manway. In such cases a vapor space at loading temperature equivalent to or larger than the DOT outage limits
(2% is common for most materials, 5% is normally adequate for materials poisonous by inhalation) is
recommended and an accurate loading temperature is not required for target outage calculation.
A.3
General Purpose Cars
A.3.1 To avoid overloading a car by weight, the weight of the maximum amount of liquid allowed by volume
must be determined. To calculate this amount, multiply the stenciled capacity by the DOT maximum fraction of
14
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
liquid allowed (MFLA, 0.99 in most cases), correct the liquid volume and the tank car shell volume (optional)
from the statutory temperature to reference temperature, and multiply by the liquid’s density at reference
temperature in pounds per gallon:
Wma
= Vs (MFLA) (CTLstat) (CTSstat)* (dref)
Wma
= weight maximum allowed by volume, pounds,
Vs
= stenciled volume, gallons,
(A.1)
where
MFLA = DOT maximum fraction of liquid allowed (0.99 or 0.95, or 0.98 for hot loading),
CTLstat = CTL at statutory temperature,
CTSstat* = CTS at statutory temperature,
dref
= density at reference temperature.
* = optional
A.3.2 If Wma exceeds the car’s Load Limit, the Load Limit will determine the maximum volume of liquid the
car can contain. To calculate this, divide the Load Limit by dref to find the reference volume. Next, divide the
reference volume by the CTL and CTS (optional) at loading temperature to find the volume at loading
temperature. This volume is then divided by the capacity table adjustment factor and that result is entered into the
car’s capacity table to find the corresponding gauge. If there is no volume match, the next smaller liquid volume
in the table is chosen. One may wish to interpolate volumes and their gauges to the nearest 1/8 inch
GOV =
Wll
(dref) (CTL) (CTS)* (CTAF)
(A.2)
where
GOV = volume to be looked up in capacity table,
Wll = Load Limit weight,
CTL = CTL at load temperature,
CTS* = CTS at load temperature,
CTAF = Capacity Table Adjustment Factor (stenciled volume divided by the car’s maximum capacity table
volume).
* = optional
A.3.3 If Wma does not exceed the car’s Load Limit, the statutory outages apply (for cool loading). To calculate
this, multiply the stenciled volume by the MFLA, correct the volume to 60°F by multiplying by the CTL and CTS
(optional) for the statutory temperature, divide by the CTL and CTS (optional) at loading temperature, divide by
the capacity table adjustment factor, and look up the corresponding (or next smaller) liquid volume in the
capacity table.
GOV =
Vs (MFLA) (CTLstat) (CTSstat)*
(CTL) (CTAF) (CTS)*
= Vs (MFLA) (CTLstat) (CTSstat)*
(CTL) (Vs/Vtblmax) (CTS)*
= Vtblmax (MFLA) (CTLstat) (CTSstat)*
(CTL) (CTS)*
* = optional
(A.3)
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
15
A.3.4 If the car is being loaded hot (above the statutory temperature) and Wma does not exceed the car’s Load
Limit, multiply the stenciled volume by the MFLA of 0.98 (0.95 for materials deemed poisonous by inhalation),
divide by the capacity table adjustment factor, and look up the gauge in the table as above.
GOV = Vs (0.98)
CTAF
(A.4)
Weight overload checks and corresponding allowable outages are performed as above, except using CTL at
loading temperature in place of CTLstat to solve for Wma.
A.4
Pressure Cars
To avoid overloading a pressure car, the same procedures outlined above should be followed, with the addition of
CPS (optional) as shown below. If the pressure is higher than equilibrium vapor pressure, lighter products or inert
gases may be present and CPL may be calculated for the pressure difference, but will probably have an insignificant
effect (at or close to 1.00000). Pressure cars have a substantially greater light weight compared to general purpose
cars (on the order of 110,000 pounds versus about 76,000 pounds). If a pressure car is used for normal liquids
(resins that need a nitrogen cap, for example), the weight limitation will apply if the density at loading
temperature is above approximately 5.0 lb/gal. For liquefied gases, the statutory outages will apply as above.
A.4.1 To avoid overloading a car by weight, the weight of the maximum amount of liquid allowed by volume
must be determined.
Wma
=
Vs (MFLA) (CTLstat) (CPLstat) (CTSstat)* (CPSstat)* (dref)
Wma
=
weight maximum allowed by volume, pounds,
Vs
=
stenciled volume, gallons,
MFLA
=
DOT maximum fraction of liquid allowed (0.99 or 0.95, or 0.98 for hot loading),
CTLstat
=
CTL at statutory temperature,
(A.5)
where
=
CPLstat
CPL at normal final loaded pressure,
CTSstat
=
CTS at statutory temperature,
CPSstat
=
CPS at statutory temperature,
dref
=
density at reference temperature.
* = optional
A.4.2 If Wma exceeds the car’s Load Limit, the Load Limit will determine the maximum volume of liquid the car
can contain.
GOV =
Wll
(dref) (CTL) (CPL) (CTS)* (CPS)* (CTAF)
(A.6)
where
GOV = volume to be looked up in capacity table,
Wll = Load Limit weight,
CTL = CTL at load temperature,
CPL = CPL at normal final loaded pressure,
CTS = CTS at load temperature,
CPS = CPS at normal final loaded pressure,
CTAF = Capacity Table Adjustment Factor (stenciled volume divided by the car’s maximum capacity table
volume).
16
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
* = optional
A4.3. If Wma does not exceed the car’s Load Limit, the statutory outages apply (for cool loading).
GOV =
Vs (MFLA) (CTLstat) (CPLstat) (CTSstat)* (CPSstat)*
(CTL) (CTAF) (CPL) (CTS)* (CPS)*
= Vs (MFLA) (CTLstat) (CPLstat) (CTSstat)* (CPSstat)*
(CTL) (Vs/Vtblmax) (CPL) (CTS)* (CPS)*
= Vtblmax (MFLA) (CTLstat) (CPLstat) (CTSstat)* (CPSstat)*
(CTL) (CPL) (CTS)* (CPS)*
(A.7)
* = optional
Refer to Annex C for CPS calculation. Typically only loading pressure will be available, so pressure at statutory
temperature must be calculated before CPSstat can be determined. As pressure is directly proportional to
temperature in degrees Kelvin at constant volume,
Pstat = (Pload) ((Tstat – 32)*5/9 + 273.16) / ((Tload – 32)*5/9 + 273.16)
where:
Pstat = pressure at statutory temperature
Pload = pressure loaded temperature
Tstat = statutory temp, °F
Tload = loaded temp, °F
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
17
Annex B
(informative)
Calculation of Tank Car Shell Expansion / Contraction with Temperature
The equation for the expansion of a solid rod or hollow cylinder is derived in the following manner:
 = linear coefficient of expansion,
V = volume of cylinder,
V ' = expanded volume after heating,
r = radius of cylinder,
r = change in radius upon heating,
l = length of cylinder,
l = change in length of cylinder upon heating,
T = change in temperature.
 = 6.2  10-6 per °F for mild carbon steel,
= 9.6  10-6 per °F for 304 stainless steel,
= 8.83  10-6per °F for 316 stainless steel.
r =  * r * T
l =  * l * T
V =  * r2 * l
V ' = (r + r)2 (l + l) = (r2 + 2rr + r2) (l + l)
V ' = (lr2 + 2lrr + lr2 + r2l + 2rrl + r2l)
V ' = (lr2 + 2lrrT + l2r2T2 + r2lT + 2r2rlT2 + 3r2lT3)
V ' = V + 2VT + V2T2 + VT + 2V2T2 +V3T3
V ' = V + 3VT + 3V2T2 + V3T3
V'
= 1 + 3T + 32T2 + 3T3
V
V'
= (1 + T)3
V
CTS =
B-1
V'
V
This is the same equation derived for a cube, rectangular block or sphere truncated to the first two terms. The
third term is small and the last term is insignificant (6.64  10-6 and 3.3  10-9, respectively, at 300°F for carbon
steel). The equation produces Table B-1 (using the first three terms).
Table B-1 — Shell Temperature Tank Car Volume Correction Factors
Temp
CTS
Temp
CTS
Temp
CTS
Temp
CTS
Temp
CTS
Temp
CTS
Temp
CTS
Temp
CTS
18
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
0.99888
0.99890
0.99892
0.99894
0.99896
0.99898
0.99900
0.99901
0.99903
0.99905
0.99907
0.99909
0.99911
0.99913
0.99914
0.99916
0.99918
0.99920
0.99922
0.99924
0.99926
0.99927
0.99929
0.99931
0.99933
0.99935
0.99937
0.99939
0.99940
0.99942
0.99944
0.99946
0.99948
0.99950
0.99952
0.99954
0.99955
0.99957
0.99959
0.99961
0.99963
0.99965
0.99967
0.99968
0.99970
0.99972
0.99974
0.99976
0.99978
0.99980
0.99981
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
0.99983
0.99985
0.99987
0.99989
0.99991
0.99993
0.99994
0.99996
0.99998
1.00000
1.00002
1.00004
1.00006
1.00007
1.00009
1.00011
1.00013
1.00015
1.00017
1.00019
1.00020
1.00022
1.00024
1.00026
1.00028
1.00030
1.00032
1.00033
1.00035
1.00037
1.00039
1.00041
1.00043
1.00045
1.00047
1.00048
1.00050
1.00052
1.00054
1.00056
1.00058
1.00060
1.00061
1.00063
1.00065
1.00067
1.00069
1.00071
1.00073
1.00074
1.00076
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
1.00078
1.00080
1.00082
1.00084
1.00086
1.00087
1.00089
1.00091
1.00093
1.00095
1.00097
1.00099
1.00100
1.00102
1.00104
1.00106
1.00108
1.00110
1.00112
1.00114
1.00115
1.00117
1.00119
1.00121
1.00123
1.00125
1.00127
1.00128
1.00130
1.00132
1.00134
1.00136
1.00138
1.00140
1.00141
1.00143
1.00145
1.00147
1.00149
1.00151
1.00153
1.00154
1.00156
1.00158
1.00160
1.00162
1.00164
1.00166
1.00167
1.00169
1.00171
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
1.00173
1.00175
1.00177
1.00179
1.00181
1.00182
1.00184
1.00186
1.00188
1.00190
1.00192
1.00194
1.00195
1.00197
1.00199
1.00201
1.00203
1.00205
1.00207
1.00208
1.00210
1.00212
1.00214
1.00216
1.00218
1.00220
1.00222
1.00223
1.00225
1.00227
1.00229
1.00231
1.00233
1.00235
1.00236
1.00238
1.00240
1.00242
1.00244
1.00246
1.00248
1.00249
1.00251
1.00253
1.00255
1.00257
1.00259
1.00261
1.00262
1.00264
1.00266
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
1.00268
1.00270
1.00272
1.00274
1.00276
1.00277
1.00279
1.00281
1.00283
1.00285
1.00287
1.00289
1.00290
1.00292
1.00294
1.00296
1.00298
1.00300
1.00302
1.00303
1.00305
1.00307
1.00309
1.00311
1.00313
1.00315
1.00317
1.00318
1.00320
1.00322
1.00324
1.00326
1.00328
1.00330
1.00331
1.00333
1.00335
1.00337
1.00339
1.00341
1.00343
1.00344
1.00346
1.00348
1.00350
1.00352
1.00354
1.00356
1.00358
1.00359
1.00361
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
1.00363
1.00365
1.00367
1.00369
1.00371
1.00372
1.00374
1.00376
1.00378
1.00380
1.00382
1.00384
1.00386
1.00387
1.00389
1.00391
1.00393
1.00395
1.00397
1.00399
1.00400
1.00402
1.00404
1.00406
1.00408
1.00410
1.00412
1.00413
1.00415
1.00417
1.00419
1.00421
1.00423
1.00425
1.00427
1.00428
1.00430
1.00432
1.00434
1.00436
1.00438
1.00440
1.00441
1.00443
1.00445
1.00447
1.00449
1.00451
1.00453
1.00455
1.00456
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
1.00458
1.00460
1.00462
1.00464
1.00466
1.00468
1.00469
1.00471
1.00473
1.00475
1.00477
1.00479
1.00481
1.00483
1.00484
1.00486
1.00488
1.00490
1.00492
1.00494
1.00496
1.00497
1.00499
1.00501
1.00503
1.00505
1.00507
1.00509
1.00511
1.00512
1.00514
1.00516
1.00518
1.00520
1.00522
1.00524
1.00525
1.00527
1.00529
1.00531
1.00533
1.00535
1.00537
1.00539
1.00540
1.00542
1.00544
1.00546
1.00548
1.00550
1.00552
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
1.00553
1.00555
1.00557
1.00559
1.00561
1.00563
1.00565
1.00567
1.00568
1.00570
1.00572
1.00574
1.00576
1.00578
1.00580
1.00581
1.00583
1.00585
1.00587
1.00589
1.00591
1.00593
1.00595
1.00596
1.00598
1.00600
1.00602
1.00604
1.00606
1.00608
1.00609
1.00611
1.00613
1.00615
1.00617
1.00619
1.00621
1.00623
1.00624
1.00626
1.00628
1.00630
1.00632
1.00634
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
19
Annex C
(informative)
Calculation of Tank Car Shell Expansion with Pressure
The expansion due to pressure is calculated in the same manner as for meter provers (API MPMS Chapter 12.2).
CPS = 1 + (P  D) / (E  t)
C-1
where
CPS = Correction factor of pressure on steel,
P = tank car internal pressure, psig,
D = internal diameter of car = 120 inches,
t = thickness of tank car shell = 11/16 inch,
E = modulus of elasticity
= 30,000,000 psig (for mild steel),
= 28,000,000 psig (for 304 stainless steel),
= 29,000,000 psig (for 316 stainless steel).
For a typical pressure car with the values for D, t, and E given above, Table C-1 may be generated.
Table C-1 — Pressure Expansion Table for a Typical (D = 120 inches, t = 11/16 inch, mild steel)
Pressure Car
P
CPS
P
CPS
P
CPS
P
CPS
0
1.00000
80
1.00047
155
1.00090
230
1.00134
5
1.00003
85
1.00049
160
1.00093
235
1.00137
10
1.00006
90
1.00052
165
1.00096
240
1.00140
15
1.00009
95
1.00055
170
1.00099
245
1.00143
20
1.00012
100
1.00058
175
1.00102
250
1.00145
25
1.00015
105
1.00061
180
1.00105
255
1.00148
30
1.00017
110
1.00064
185
1.00108
260
1.00151
35
1.00020
115
1.00067
190
1.00111
265
1.00154
40
1.00023
120
1.00070
195
1.00113
270
1.00157
45
1.00026
125
1.00073
200
1.00116
275
1.00160
50
1.00029
130
1.00076
205
1.00119
280
1.00163
55
1.00032
135
1.00079
210
1.00122
285
1.00166
60
1.00035
140
1.00081
215
1.00125
290
1.00169
65
1.00038
145
1.00084
220
1.00128
295
1.00172
70
1.00041
150
1.00087
225
1.00131
300
1.00175
75
1.00044
20
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Annex D
(informative)
Calculation of Magnetic Gauge Offsets
D.1 General
A correction for use with nonreference temperatures and / or with nonreference liquids can be made. The
following procedure with examples is supplied for future use for incorporation into computer programs.
Databases necessary for this procedure are not presently readily available.
D.2 Determination of Magnetic Gauge Data
Magnetic float gauges are designed for service with a specific car and a specific product (reference specific
gravity). Normally the scale will be set to read zero at shell full (unless the customer requests a specific offset
from shell full). The reference gravity cannot normally be ascertained visually; one must contact the manufacturer
with the serial number off the gauge flange. As at some point the gauge rod may have been damaged and
unofficially replaced, one should also supply rod data (diameter, length, distance from top of magnet to zero pt. of
scale, and whether aluminum or fiberglass).
Figure D.1 — Magnetic Float Gauge
D.3 Derivation of Depth of Immersion Equation
The float consists of a sphere cut by a cylindrical hole (see Figure D.1). The volume of the immersed portion of
the float is the volume of the spherical segment minus the volume of the cylindrical hole in the segment and the
spherical end cap cut by the cylindrical hole (very small volume). The following data, which includes dimensions
and weights for a standard installation, are required:
R = radius of spherical float (normally 3.75 inches),
a = radius of cylindrical hole (normally 0.8345 inch),
r = radius of floating segment,
h = half height of the cylindrical hole,
b = depth float is sitting in liquid,
b' = depth of spherical end cap segment (not shown in Figure D.1),
Vd = volume of float displaced,
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
21
Weight of float = 48.5 oz.
Weight of magnet = 1.55 oz.
Weight of 3/8 inch  74 inches aluminum rod = 5.45 oz.
The general equation for the volume of a normal spherical segment (bowl) is (see paragraph D.4 below for
derivation):
V 




b b 2  3r 2  b 2 3R  b 
6
3
(D.1)
The volume of the cylindrical segment cut out of the spherical segment is:
V ” =  a2 (b – b')
The height of the end cap bowl (b') is related to the sphere’s radius (R) and the cylinder’s radius (a) as follows:
b' = R – h
R2 = h2 + a2
2
h =
 7.5   1.687 
R2  a2  
 

 2   2 
2
 14.0625  0.71149  3.6539 in.
The height of the end cap is thus:
b' = R – h =
7 .5
– 3.6539 = 0.096100 inch (not quite 3/32 inch)
2
And from equation D.1, the volume of end cap cut by cylinder is (substituting b' for b, and a for r):
V 
2


0.096100  0.096100 2  3 1.687  
6
 2  

= 0.10787 inch3
The volume of the displacing segment equals the whole segment minus the interior cylindrical hole minus the end
cap cut by the cylinder, or
Vd = V ' – V '' – V '’'
Vd =
b 2
(3R – b) – a2(b – 0.0961) – (0.10787)
3

3
Vd = Rb2 – b3 – a2b + a2(0.0961) – (0.10787)
Vd = 11.7810 b2 – 1.04720 b3 – 2.23522 b + 0.10618
(D.2)
The volume of liquid displaced by the segment is also equal to the weight of the float, magnet, and rod assembly
(in pounds) divided by the liquid’s density (ρ in pounds per gallon):
 weight   48.5  1.55  5.45oz 
  

Vd = 
 density   16oz / lb density  
 3.46875 lb   3.46875 lb 231 in.3 


 
 


 lb / gal    (lb / gal)  gal 
22
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Vd = 
801.28125 lb  in.3 
801.28125

in.3
(lb / gal)  gal  density @ 60 F
(D.3)
Density (pounds per gallon) at 60°F is derived from relative density (RD) by:
density = RD * density of water at 60°F * 8.3454
It is then multiplied by 231 inch3 / gallon to obtain pounds per inch3, and that result is divided into the weight of
the gauge assembly to obtain Vd. Equation (D.3) may then be inserted into equation (D.2) and solved for b. Thus
we can guess a value for b and see how close the right part of equation (D.2) is to the right part of equation (D.3).
If they are not close, we can increment b up or down by a small amount and try again. By repeating this process
over and over until equation (D.2) is just under or equal to equation (D.3), we can find the true value of b specific
to the product. This process can be easily accomplished by a macro in a spreadsheet.
D.4 Gauge Offset Calculations
D.4.1 General
A gauge floating in a liquid with a lower relative density than the reference will sink deeper into the liquid, thus
giving a larger outage gauge (there will appear to be less liquid in the car). A gauge floating in a liquid with a
higher relative density than the reference will float higher, thus giving a smaller outage gauge (there will appear to
be more liquid in the car). Temperature change produces the same effect. A temperature higher than the reference
temperature (normally 60°F) will lower the fluid’s relative density; conversely, a lower temperature will raise the
fluid’s relative density.
D.4.2 Example 1: Relative Density Offset
Calculate the gauge offset at 60°F due to the difference in relative density between the gauge’s reference relative
density (0.5000) and a product of relative density 1.0000 (water). The depth of the submerged part of the float (b)
must be calculated for both liquids; the difference is the offset.
Step 1. Calculate the immersion depth in the reference liquid. The reference liquid’s relative density of 0.5000 is
equivalent to a density of 4.1686 lb/gal. The volume displaced is thus:
 55.5 16 
  192.21831 in.3
4
.
1686
231


Vd  
= 11.7810 b2 – 1.04720 b3 – 2.23522 b + 0.01618
(D.4)
One can set up the spreadsheet so that rough guesses can be made for b. When the right half of equation (D.4) is
close to 192.21831, start the iteration in increments of 0.001 inch (one thousandth of an inch) or less. For
instance:
increment b = 0.001
increment b = 0.0001
Vd = 192.21152 inches3
Vd = 192.21788 inches3
b = 6.3210 inches
b = 6.3213 inches
This 0.0003 inch difference is insignificant when one considers the required 1/8 inch accuracy (1/8 inch = 0.125
inch, 1/16 inch = 0.0625 inch, 1/32 inch = 0.0313 inch, 1/64 inch = 0.0156 inch, 1/128 inch = 0.00781 inch, etc.). This
means that the float is immersed 6.321 inches in the reference liquid at 60°F. The gauge’s scale has been adjusted
to read zero inches when the liquid level at 60°F is at the shell-full point and the float is immersed 6.321 inches.
Step 2. Calculate the immersion depth in the non-reference liquid. Its relative density of 1.0000 is equivalent to a
density of 8.3372 pounds / gallon. The volume displaced is thus:
 55.5 16 
  96.10916 in.3
Vd  
8
.
3372
231


=11.7810 b2 – 1.04720 b3 – 2.23522 b + 0.01618
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
23
Solving for b as in the previous example:
increment b = 0.001
increment b = 0.0001
Vd = 96.09288 inches3
Vd = 96.10544 inches3
b = 3.6050 inches
b = 3.6053 inches
Again, the 0.0003-inch difference is insignificant. This means that the float is immersed 3.605 inches in the nonreference liquid at 60°F.
Step 3. For these two extreme examples (specific gravity 0.500 and 1.000), the float sets 6.321 – 3.605 = 2.716
inches (or roughly 1/32 inch less than 2 3/4 inches) higher in the water. Thus, the gauge indicates 2.716 inches
more product in the car than is actually there.
D.4.3 Example 2: Temperature Offset For A Reference Relative Density Of 0.5000
Calculate the gauge offset arising from using a float for service at non-reference temperatures. The depth of the
submerged part of the float (b) must be calculated at reference temperature and operating temperature; the
difference is the offset.
Calculate the immersion depth of the reference liquid (relative density 0.5000, 4.1686 pounds / gallon) at various
non-reference temperatures. The density of the liquid in equation (D.3) at a non-reference temperature is the
density at reference temperature multiplied by the liquid’s CTL. CTLs are obtained from the appropriate API /
ASTM table. The volume displaced at various temperatures is thus:

55.5 16

 
Vd  
 VCF4.1686 231 
192.21831 in.3
 11.7810 b 2  1.04720 b 3  2.23522 b  0.01618
VCF
For each temperature, obtain the CTL and calculate the volume displaced at that temperature, then solve for b as
above.
Temp
(°F)
CTL
b (in.)
Vd for b
(in.3)
20
30
40
50
60
70
80
90
1.064
1.049
1.033
1.017
1.000
0.983
0.965
0.946
5.853
5.947
6.057
6.177
6.310
6.489
6.711
7.082
180.63879
183.21619
186.07703
188.99762
192.21152
195.53639
199.18006
203.18841
b@60°F – b
0.457
0.363
0.253
0.133
0.000
– 0.179
– 0.401
– 0.772
Offset
4
/8 in.
/8 in.
2
/8 in.
1
/8 in.
0 in.
– 1/8 in.
– 3/8 in.
– 6/8 in.
3
This float assembly sinks at 92°F. Note that the float is about 87% immersed at 60°F. The offset is added or
subtracted, as indicated by its sign, from the observed gauge to obtain the true liquid level.
D.4.4 Example 3: Temperature Offset For A Reference Relative Density Of 1.0000
Calculate the immersion depth for a petroleum product reference liquid (relative density 1.0000, 8.3372 lb/gal,
10 API) at a various non-reference temperatures. The density of the liquid in equation (D.3) at a non-reference
temperature is the density at reference temperature multiplied by the liquid’s CTL. CTLs are obtained from API
Table 6B. The volume displaced at various temperatures is thus:

55.5 16

 
Vd  
 VCF8.3372  231 
96.1092 in.3
VCF
 11.7810 b 2  1.04720 b 3  2.23522 b  0.01618
24
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
For each temperature, obtain the CTL and calculate the volume displaced at that temperature, then solve for b as
above.
Temp
(°F)
CTL
20
60
200
1.01491
1.00000
0.94683
b (in.) Vd for b (in.3)
3.571
3.605
3.734
94.66961
96.09288
101.50039
b@60° F – b
0.034
0.000
– 0.129
Offset
1
/32 in.
0 in.
– 1/8 in.
Note that the float is roughly half immersed at 200°F and has sunk only 1/8 inch from its position at 60°F. These
two extremes (Examples 2 and 3) show that the lower the relative density, the more effect temperature has.
D.5 Derivation of Volume Segment or Bowl (Equation D.1)
Strategy: Offset a sphere from the origin by its radius R and add up the volume of the small circular segments of
thickness, dx within it from x = 0 to x = b:
Figure D.2 — Derivation of a Spherical Volume
Segment or Bowl
V   dv   y 2 dx    R 2  R  x  dx
V
V
b
b
b
0
o
o

b
o
R 2 dx  

b
2
 R  x  dx
2
o

b
xR 2 o   R 2 x

x 3 
 Rx 

3 
b
2
 
o


b3 
b3 
V   bR 2  R 2 b  Rb 2     Rb 2  
3 
3 



 b 2 3R  b 
3
If the radius of the segment is r,
R2 = (R – b)2 + r2
R2 = R2 – 2bR + b2 + r2
R
b2  r 2
2b
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
Substituting into the volume equation above,


V

 2  b 2  r 2
b 3
 b


3 
2b

V
b 2
b  3r 2
6


25
26
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Annex E
(informative)
Tank Car Reconciliation
Custody transfer measurement of tank car cargos is usually performed both at loading and at discharge, however
the methods of measurement at the locations will often vary.
The most accurate method is direct static weighing at the rack before and after cargo transfer with a properly
calibrated scale, but that is seldom encountered on either end of a movement.
Coupled-in-motion scales located at some point between the loading and unloading racks are more often used, but
this more complex method is subject to more sources of uncertainty (track condition, speed, car identification,
etc.), and not all such scales are of custody transfer quality. Carrier scales are intended primarily for freight
weight confirmation and do not meet custody transfer measurement standards.
Most rack meters are not maintained to custody transfer standards but are instead used for controlling pumps. If a
meter is used for custody transfer measurement, it should conform to API MPMS standards.
Custody transfer quality manual gauging and temperature measurement, as described in this standard and API
MPMS Chapt 3.2, can be as accurate as static scale measurement. Figure E-1 illustrates a review of twenty-two
months of butane receipts. The seller billed off calculations from manual custody transfer measurements as
described in this standard and the customer verified billing via a static scale, subtracting the car’s stenciled tare
weight to determine total unloaded weight. The % Difference for each sale was calculated as follows:
% Difference = (customer weight – billing weight) * 100
billing weight
Note that differences of + 2% were common. Industry practice is to allow a + 0.50% difference, but Figure E-1
illustrates why reconciliation of large groups of cars is more productive than attempting to reconcile individual
cars.
Butene
Static Scale - BOL Difference
Average -0.20%
10.00%
8.00%
% Difference
6.00%
4.00%
2.00%
0.00%
1
7
13
19
25
31
37
43
49
55
61
67
73
79
85
91
97
-2.00%
-4.00%
-6.00%
-8.00%
Figure E-1
The – 0.20% at first appears to be a 0.20% shortage to the customer. However, scale weights are in air, while
calculated weights are in vacuo. The in air vs in vacuo difference for butane is – 0.20%, making the true average
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
27
difference 0.00%. Even a long term + 0.5% gain/loss, indicating a possible measurement bias, would not always
initiate a measurement investigation, depending on the parties involved and the value of the product.
The observed fluctuation is in part explained by the fact that the tare weights stenciled on the side of the cars is
not always accurate. The tare weights are normally obtained when the car is manufactured. Over the life of the
car equipment may be added or subtracted, but due to expense and logistical concerns, the cars are seldom
reweighed. Figure E-2 is the result of measurement review where random cars were cleaned and weighed
statically. Six out of nineteen cleaned cars (32%) weighed statically were over +500 lbs off their stenciled light
weights (2,050, 700, -1,000, 700, -700, and -950 lbs). These errors are on the order of + 0.4-0.6% of the product
weight of a fully loaded car (ignoring the first point). Thirty-two percent stenciled light weight error is unacceptable,
but unfortunately the reality. There have been reports that differences of 3,000 lb. have been observed.
Customers using stenciled light weights and who only order a few cars per year may very well believe they are
being over-billed on individual cars. However, the average scale vs stenciled difference for those 19 cars was 34
lb. This illustrates how the differences average toward zero as more cars are considered.
Actual Tare minus Stenciled Wt
2,500
2,000
1,500
lbs
1,000
500
0
0
2
4
6
8
10
12
14
16
18
20
-500
-1,000
-1,500
Figure E-2
If either party wishes to initiate a loss/gain review, several steps are recommended:
a. Gather billing and receiving records for as long a period as possible, plot the percent difference as in Figure
E-1, and calculate the overall average percent difference.
b. Decide how much product value is at stake – an investigation may cost more than the amount of product in
question.
c. Visit each shipping and receiving location involved and ensure that their measurement practices follow API
custody transfer measurement standards.
d. If applicable, ensure that each end of the movement is using the same density and CTL tables and performing
the same calculations.
e. If necessary, observe the loading of one or more cars, then personally manually gauge and temperature the
car(s) at destination before unloading, and observe the actual measurement by receiving personnel.
f.
Advise patience. This type of investigation can take several months.
28
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Annex F
(informative)
Calculation Examples
F.1 General
The following examples necessarily display rounded input data and intermediate calculation results (CTAF, CTL,
CTS, CPS), therefore those rounded values have been used to obtain the final results shown. Unrounded
intermediate calculations may produce a slightly different final result.
F.2 Example 1: Outage Liquid Capacity Table — Loading Target Calculation — Volume
Limitation
A general purpose car is to be loaded with Isopropyl Alcohol.
Tank Car Data
Product Data
Tare:
67,900 pounds
Estimated Loading Temperature:
85°F
Load Limit:
195,100 pounds
Manway Nozzle Height:
12.500 in.
Stenciled Volume:
30,168 gallons
CTL Table 6C (alpha value):
API 6C (0.000578)
Capacity Table:
Table F-1
Density at Reference Temp:
6.574 pounds / gallon
Insulated?
No
Statutory Temp:
115°F
Vtblmax
30,154 gallons
MFLA
0.9900
CTSstat
1.00102 (Equat. B-1)
CTLstat
0.96792 (API 6C)
CTS85
1.00047 (Equat. B-1)
CTL85
0.98549 (API 6C)
The weight corresponding to the statutory volume limitation must be calculated using Equation (A.1).
Wma
= Vs (MFLA) (CTLstat) (CTSstat) (dref),
= (30,168) (0.9900) (0.96792) (1.00102) (6.574),
= 190,236 pounds
Since this is less than the Load Limit, the car can be loaded to statutory volume limits. If the Load Limit is not
available, add Wma to the Tare (67,900 + 190,236 = 258,136) and compare with the weight limitation for that
particular car (263,000 pounds for this car).
One must now determine the target outage (liquid level) derived from the statutory volume using Equation (A.3).
GOV
= Vtblmax (MFLA) (CTLstat) (CTSstat)
(CTL85) (CTS85)
= (30,154) (0.9900) (0.96792) (1.00102)
(0.98549) (1.00047)
= 29,336 gallons
Looking up this volume in the capacity table, it falls between volumes representing 7.500 inches and 7.750 inches
Interpolating to the nearest 1/8 inch, 7.625 inches is equal to:
(29,375 – 29,334) / 2 + 29,334 = 29,355 gallons
Since GOV is less than the volume corresponding to 7.625 inches, we round to the outage corresponding to a
smaller liquid volume, 7.750 inches. We do not round up to the outage corresponding to a larger volume (7.625
inches). If we wish to measure only to the nearest 1/4 inch, we would choose 7.750 inches.
If measuring from the top of the manway, we must add the manway nozzle height to this value.
7.750 in. + 12.500 in. = 20.250 in.
or, if to the nearest 0.250 inch:
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
29
8.000 in. + 12.500 in. = 20.250 in.
If corrections for the optional shell expansion due to temperature are omitted, Wma is 190,043 lbs, GOV is
29,320 gal, which is equal to a 7.875 inch outage, or 8.000 inches if rounding to the nearest 0.250 inch.
F.3 Example 2: Outage Liquid Capacity Table — Actual Loaded Calculation
A general purpose car is loaded with isopropyl alcohol close to the target outage determined in Example 1.
Tank Car Data
Product Data
Tare:
67,900 pounds
Loaded Temperature:
87°F
Load Limit:
195,100 pounds
Manway Nozzle Height:
12.500 in.
Stenciled Volume:
30,168 gallons
CTL Table (alpha value):
API 6C (0.000578)
Capacity Table:
Table F-1
Density at Reference Temp:
6.574 pounds / gallon
Insulated?
No
Statutory Temp:
115°F
Vtblmax
30,154 gallons
MFLA
0.9900
CTS87
1.00050 (Equat. B-1)
CTLstat
0.96792 (API 6C)
CTL87
0.98432 (API 6C)
Outage Gauge (from top of manway):
20.625 in.
%S&W
0.0%
Net Standard Volume is determined with Equation (5).
GOVtbl:
The capacity table (Table E-1) volumes do not include a nozzle height, so one must first subtract the manway
nozzle height from the outage gauge:
20.625 in. – 12.500 in. = 8.125 in.
Since the capacity table is an Outage Liquid table in quarter-inch increments, one must interpolate between the
entries for 8.00 inches and 8.25 inches:
(29,292 – 29,250) / 2 + 29,250 = 29,271 gallons
NSV = (GOVtbl) (CTAF) (CTL87) (CTS87)
= (29,271) (30,168 / 30,154) (0.98432) (1.00050)
= 28,840 gallons
The cargo’s weight (Equation 3) is:
W = NSV (dref) = 28,840 (6.574) = 189,594 pounds
Overload check by volume, using Equations (8) and (9):
MFLL
= (GOVtbl) (CTAF) (CTL87) (CTS87)
(CTSstat) (CTLstat) (Vs)
= (29,271) (30,168/30,154) (0.98432) (1.00050)
(1.00102) (0.96792) (30,168)
= 0.9867
Vapor space % = 100 - 0.9867 * 100 = 1.33%
Since the loaded liquid fraction at 115°F would be less than 0.9900 the car is not overloaded by volume.
Since the vapor space at 115°F would be greater than 1.00%, the car is not overloaded by volume.
Overload check by weight:
30
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
1. Compare cargo weight calculated above to Load Limit weight. 189,594 pounds is less than 195,100 pounds, or
2. Add Tare weight to cargo weight calculated above and compare to statutory limit:
67,900 + 189,594 = 257,494 pounds, which is less than 263,000 pounds
Thus, the car is not overloaded by weight.
If corrections for the optional shell expansion due to temperature are omitted,, NSV is 28,825 gal, W is 189,498
lb, and the vapor space % at 115°F is 1.28%.
F.4 Example 3: Outage Liquid Capacity Table — Loading Target Calculation — Weight Limitation
The same general purpose car used in Examples 1 and 2 is to be loaded with Hexylene Glycol.
Tank Car Data
Product Data
Tare:
67,900 pounds
Estimated Loading Temperature:
70°F
Load Limit:
195,100 pounds
Manway Nozzle Height:
12.500 in.
Stenciled Volume:
30,168 gallons
CTL Table:
Private Table
Capacity Table:
Table F-1
Density at Reference Temp:
7.710 pounds / gallon
Insulated?
No
Statutory Temp:
115°F
Vtblmax
30,154 gallons
MFLA
0.99
CTSstat
1.00102 (Equat. B-1)
CTLstat
0.97679
CTS70
1.00019 (Equat. B-1)
CTL70
0. 99570
The weight corresponding to the statutory volume limitation must be calculated using Equation (A.1).
Wma
= Vs (MFLA) (CTLstat) (CTSstat) (dref)
= (30,168) (0.99) (0.97679) (1.00102) (7.710)
= 225,154 pounds
Since this is greater than the Load Limit, the car cannot be loaded to statutory volume limits. If the Load Limit is
not available, add Wma to the Tare (67,900 + 225,154 = 293,054) and compare with the weight limitation for that
particular car (263,000 pounds for this car).
One must now determine the target outage (liquid level) derived from the statutory weight using Equation (A.2).
GOV =
=
Wll
(dref) (CTL70) (CTS70) (CTAF)
(263,000 – 67,900)
(7.710) (0.99570) (1.00019) (30,168 / 30,154)
= 25,397 gallons
Looking up this volume in the capacity table, it falls between volumes representing 25.750 inches and 26.000
inches Interpolating to the nearest 1/8 inch, 25.875 inches is equal to:
(25,416 – 25,350) / 2 + 25,350 = 25,383 gallons
Since GOV is greater than the volume corresponding to 25.875 inches, we round to the outage corresponding to a
smaller liquid volume, 25.875 inches. We do not round up to the outage corresponding to a larger volume
(25.750 inches). If we wish to measure only to the nearest 1/4 inch, we would choose 26.000 inches.
If measuring from the top of the manway, we must add the manway nozzle height to this value:
25.875 in. + 12.500 in. = 38.375 in.
or, if to the nearest 0.250 inch:
26.000 in. + 12.500 in. = 38.500 in.
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
31
If corrections for the optional shell expansion due to temperature are omitted, Wma is 224,925 lbs, and GOV70 is
25,402 gal, giving the same outage.
F.5 Example 4: Outage Liquid Capacity Table with Nozzle Height Included — Loading Target
Calculation — Volume Limitation
A two compartment general purpose car is to be loaded with Odorless Mineral Spirits in the first compartment.
Tank Car Data
Product Data
Tare:
67,200 pounds
Estimated Loading Temperature:
35°F
Load Limit:
195,800 pounds
Manway Nozzle Height:
12.500 in.
Stenciled Volume:
11,348 gallons
CTL Table (API gravity):
API 6B (55.1)
Capacity Table:
Table F-3
Density at Reference Temp:
6.322 pounds / gallon
Insulated?
No
Statutory Temp:
115°F
Vtblmax
11,348 gallons
MFLA
0.99
CTSstat
1.00102 (Equat. B-1)
CTLstat
0.96348
CTS35
0.99954 (Equat. B-1)
CTL35
1.01635
The weight corresponding to the statutory volume limitation must be calculated using Equation (A.1).
Wma
= Vs (MFLA) (CTLstat) (CTSstat) (dref)
= (11,348) (0.99) (0.96348) (1.00102) (6.322)
= 68,501 pounds
Since this is less than the Load Limit, the car can be loaded to statutory volume limits if the second
compartment is still empty. If the Load Limit is not available, add Wma to the Tare (67,200 + 68,501 = 135,701)
and compare with the weight limitation for that particular car (263,000 pounds for this car). If the second
compartment has been loaded, the cargo weight will have to be subtracted from the Load Limit (or added to the
Tare weight and subtracted from the weight limitation) to get the maximum amount allowed.
If the second compartment is empty, one can now determine the target outage (liquid level) derived from the
statutory volume using Equation (A.3).
GOV
= (Vtblmax) (MFLA) (CTLstat) (CTSstat)
(CTL35) (CTS35)
= (11,348) (0.99) (0.96348) (1.00102)
(1.01635) (0.99954)
= 10,666 gallons
Looking up this volume in the capacity table, it falls at the volume representing 24.25 inches and no table
interpolation is needed.
Since this table includes a 12.5-inches manway nozzle, we must subtract that value if using an instrument that
measures from the top inside of the shell to the liquid surface.
24.250 in. – 12.500 in. = 11.750 in.
If corrections for the optional shell expansion due to temperature are omitted, Wma equals 68,431 lb and GOV is
10,650 gal. Looking this up in the capacity table, it falls between volumes representing 24.25 inches and 24.5
inches. Interpolation to the nearest 1/8 inch, 24.375 in., shows:
(10,666 – 10,645) / 2 + 10,645 = 10,656 gallons
Rounding to the smaller liquid volume, we choose 24.500 inches. We do not round up to the outage
corresponding to a larger volume (24.375 inches). If we wish to measure only to the nearest 1/4 inch, we would
also choose 24.500 inches.
32
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Since this table includes a 12.500 inch manway nozzle, we must subtract that value if using an instrument that
measures from the top inside of the shell to the liquid surface.
24.500 in. – 12.500 in. = 12.000 in.
If the second compartment is already loaded, one must calculate the weight corresponding to the statutory volume
limitation using a different Load Limit. Assume the cargo in the second compartment weighs 66,140 pounds and
the first compartment Wma is 68,501 lb as shown above. This must be compared to the new Load Limit of:
263,000 – 67,200 – 66,140 = 129,660 pounds
or 195,800 – 66,140 = 129,660 pounds
Since Wma is easily within this limit, we can use the statutory volume limit as above. If it were not, we would
proceed as shown in Example 3.
F.6 Example 5: Outage Liquid Capacity Table with Nozzle Height Included — Actual Loaded
Calculation
A two-compartment general purpose car is loaded with Odorless Mineral Spirits in the first compartment, close to
the outage determined in Example 4.
Tank Car Data
Product Data
Tare:
67,200 pounds
Loaded Temperature:
39°F
Load Limit:
195,800 pounds
Manway Nozzle Height:
12.500 in.
Stenciled Volume:
11,348 gallons
CTL Table (API gravity):
API 6B (55.1)
Capacity Table:
Table F-3
Density at Reference Temp:
6.322 pounds / gallon
Insulated?
No
Statutory Temp:
115°F
Vtblmax
11,348 gallons
MFLA
0.99
CTS39
0.99961 (Equat. B-1)
CTLstat
0.96348
CTL39
1.01375
Outage Gauge (from inside shell top):
11.875 in.
%S&W
0.0%
Net Standard Volume is determined with Equation (5).
GOVtbl:
The capacity table (Table E-3) volumes include a nozzle height, so if one is using a gauging instrument that
does not include the manway, one must first add the manway nozzle height to the outage gauge:
11.875 in. + 12.500 in. = 24.375 in.
Since the capacity table is an Outage Liquid table in quarter-inch increments, one must interpolate between the
entries for 24.250 inches and 24.500 inches:
(10,666 – 10,645) / 2 + 10,645 = 10,656 gallons
NSV
= GOVtbl (CTAF) (CTL39) (CTS39)
= (10,656) (11,348 / 11,348) (1.01375) (0.99961)
= 10,798 gallons
The cargo’s weight is determined with equation (3):
W = NSV (dref) = 10,798 (6.322) = 68,265 pounds
Overload check by volume, using Equation (8) and (9):
MFLL = (GOVtbl) (CTAF) (CTL39) (CTS39)
(CTSstat) (CTLstat) (Vs)
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
33
= (10,656) (11,348 / 11,348) (1.01375) (0.99961)
(1.00102) (0.96348) (11,348)
= 0.9866
Vapor space % = 100 - 0.9866 * 100 = 1.34%
Since the loaded liquid fraction at 115°F would be less than 0.9900 the car is not overloaded by volume.
Since the vapor space at 115°F would be greater than 1.00%, the car is not overloaded by volume.
We know from the Target calculations in Example 4 that we cannot overload this product in this car by weight.
However, if we did not know that, we would have to again consider the loading status of the second compartment.
If the second compartment is empty:
1. Compare cargo weight calculated above to Load Limit weight. 68,265 pounds is less than 195,800 pounds, or
2. Add Tare weight to cargo weight calculated above and compare to statutory limit:
67,200 + 68,265 = 135,465 pounds, which is less than 263,000 pounds.
If the second compartment is filled with 66,140 pounds of product:
1. Compare the sum of the calculated weights to the Load Limit weight of 195,800 lb.
68,267 + 66,140 = 134,407 pounds, or
2. Add the Tare weight to both cargo weights and compare to the statutory limit:
67,200 + 68,265 + 66,140 = 201,605 pounds, which is less than 263,000 pounds
Thus, the car is not overloaded by weight.
If corrections for the optional shell expansion due to temperature are omitted, NSV is 10,803 gal, W is 68,297 lb,
and the vapor space % at 115°F is 1.20%.
F.7 Example 6: Outage Vapor Capacity Table — Loading Target Calculation — Volume Limitation
A general purpose car is to be loaded with Light Cat Cracked Gasoline.
Tank Car Data
Product Data
Tare:
72,700 pounds
Estimated Loading Temperature:
95°F
Load Limit:
190,300 pounds
Manway Nozzle Height:
9.500 in.
Stenciled Volume:
23,639 gallons
CTL Table (API gravity):
API 6B (65.0)
Capacity Table:
Table F-2
Density at Reference Temp:
6.004 pounds / gallon
Insulated?
Yes
Statutory Temp:
105°F
Vtblmax
23,679 gallons
MFLA
0.99
CTSstat
1.00084 (Equat. B-1)
CTLstat
0.96772 (API 6B)
CTS95
1.00065 (Equat. B-1)
CTL95
0.97494 (API 6B)
The weight corresponding to the statutory volume limitation must be calculated using equation (A.1).
Wma
= Vs (MFLA) (CTLstat) (CTSstat) (dref)
= (23,639) (0.99) (0.96772) (1.00084) (6.004)
= 136,088 pounds
34
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Since this is less than the Load Limit, the car can be loaded to statutory volume limits. If the Load Limit is not
available, add Wma to the Tare (72,700 + 136,088 = 208,788) and compare with the weight limitation for that
particular car (263,000 pounds for this car).
One must now determine the target outage (liquid level) derived from the statutory volume using equation (A.3).
GOV = Vtblmax (MFLA) (CTLstat) (CTSstat)
(CTL95) (CTS95)
= (23,679) (0.99) (0.96772) (1.00084)
(0.97494) (1.00065)
= 23,273 gallons
Since the capacity table is an Outage Vapor, the volumes listed are vapor volumes. To convert GOV to its
corresponding vapor volume, subtract GOV from the maximum vapor volume in the table:
23,679 – 23,273 = 406 gallons vapor
Looking up this volume in the capacity table, it falls between volumes representing 3.75 inches and 4 inches.
Interpolating to the nearest 1/8 inch, 3.875 inches is equal to:
(381 – 412) / 2 + 412 = 397 gallons
Since GOV is greater than the volume corresponding to 3.875 inches, we round to the outage corresponding to a
larger vapor volume, 4.000 inches. We do not round up to the outage corresponding to a smaller vapor volume
(3.875 inches). If we wish to measure only to the nearest 1/4 inch, we would choose 4.000 inches.
If measuring from the top of the manway, we must add the manway nozzle height to this value:
4.000 in. + 9.500 in. = 13.500 in.
If corrections for the optional shell expansion due to temperature are omitted, Wma = 135,974 lb, well within the
load limit, GOV = 23,269 gal, which is 410 gal of vapor, equivalent to just over 4.0 in. as above.
F.8 Example 7: Outage Vapor Capacity Table — Loading Target Calculation — Understated
Loading Temperature
A general purpose car is to be loaded with Light Cat Cracked Gasoline. However, here the assumed loading
temperature is 60°F instead of the real 95°F as shown in Example 6.
Tank Car Data
Product Data
Tare:
72,700 pounds
Estimated Loading Temperature:
60°F
Load Limit:
190,300 pounds
Manway Nozzle Height:
9.250 in.
Stenciled Volume:
23,639 gallons
CTL Table (API gravity):
API 6B (65.0)
Capacity Table:
Table F-2
Density at Reference Temp:
6.004 pounds / gallon
Insulated?
Yes
Statutory Temp:
105°F
Vtblmax
23,679 gallons
MFLA
0.99
CTSstat
1.00084 (Equat. B-1)
CTLstat
0.96772 (API 6B)
CTS60
1.00000 (Equat. B-1)
CTL60
1.00000 (API 6B)
The weight corresponding to the statutory volume limitation must be calculated using equation (A.1).
Wma
= Vs (MFLA) (CTLstat) (CTSstat) (dref)
= (23,639) (0.99) (0.96772) (1.00084) (6.004)
= 136,088 pounds
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
35
Since this is less than the Load Limit, the car can be loaded to statutory volume limits. If the Load Limit is not
available, add Wma to the Tare (72,700 + 136,088 = 208,788) and compare with the weight limitation for that
particular car (263,000 pounds for this car).
One must now determine the target outage (liquid level) derived from the statutory volume using equation (A.3).
GOV = (Vtblmax) (MFLA) (CTLstat) (CTSstat)
(CTL60) (CTS60)
= (23,679) (0.99) (0.96772) (1.00084)
(1.00000) (1.000000)
= 22,705 gallons
Since the capacity table is an Outage Vapor, the volumes listed are vapor volumes. To convert GOV to its
corresponding vapor volume, subtract GOV from the maximum vapor volume in the table:
23,679 – 22,705 = 974 gallons vapor
Looking up this volume in the capacity table, it falls between volumes representing 7.750 inches and 8.000
inches. Interpolating to the nearest 1/8 inch, 7.875 inches is equal to:
(945 – 984) / 2 + 984 = 965 gallons
Since vapor volume is more than the volume corresponding to 7.875 inches, we round to the outage
corresponding to a larger vapor volume, 8.000 inches. We do not round up to the outage corresponding to a
smaller vapor volume (7.875 inches). If we wish to measure only to the nearest 1/4 inch, we would still choose
8.000 inches.
If measuring from the top of the manway, we must add the manway nozzle height to this value.
8.000 in. + 9.250 in. = 17.250 in.
Notice, comparing Example 6 to Example 7, that by ignoring the actual loaded temperature of 95°F and using
60°F, one will underload the car by 4.000 inches, or 572 gallons. Thus, it is always best to determine the loading
temperature as accurately as possible. This example also illustrates the converse – one must not overestimate the
actual loading temperature or the target calculation will result in overloading the car (see Example 9).
F.9 Example 8: Outage Vapor Capacity Table — Actual Loaded Calculation
A general purpose car is loaded with Light Cat Cracked Gasoline close to the target outage determined in
Example 6.
Tank Car Data
Product Data
Tare:
72,700 pounds
Loaded Temperature:
97°F
Load Limit:
190,300 pounds
Manway Nozzle Height:
9.250 in.
Stenciled Volume:
23,639 gallons
CTL Table (API gravity):
API 6B (65.0)
Capacity Table:
Table F-2
Density at Reference Temp:
6.004 pounds / gallon
Insulated?
Yes
Outage Gauge (from top of manway):
13.5 in.
Vtblmax
23,639 gallons
Statutory Temp:
115°F
CTS97
1.00069 (Equat. B-1)
MFLA
0.99
CTLstat
0.96772
CTL97
0.97350
Outage Gauge (from top of manway):
13.500 in.
%S&W
0.0%
Net Standard Volume is determined with equation (5).
36
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
GOVtbl: The capacity table (Table E-2) does not include a nozzle height, so one must first subtract the manway nozzle
height from the outage gauge:
13.500 in. – 9.250 in. = 4.250 in.
Since the capacity table is an Outage Vapor table in quarter-inch increments, one need not interpolate
for 4.250 inches, but must subtract the corresponding vapor volume from the table maximum volume.
The resulting liquid volume is:
(23,679 – 444) = 23,235 gallons
NSV
= GOV (CTAF) (CTL97) (CTS97)
= (23,235) (23,639 / 23,679) (0.97350) (1.00069)
= 22,597 gallons
The cargo’s weight is determined, as determined with equation (3), is less than the load limit:
W = NSV (dref) = 22,597 (6.004) = 135,672 pounds
Overload check by volume, using equations (8) and (9):
MFLL = (GOVtbl) (CTAF) (CTL97) (CTS97)
(CTSstat) (CTLstat) (Vs)
= (23,235) (23,639 / 23,679) (0.97350) (1.00069)
(1.00084) (0.96772) (23,639)
= 0.9870%
Vapor Space % = 100 – 0.9870 * 100 = 1.30%
Since the loaded liquid fraction at 105°F would be less than 0.9900 the car is not overloaded by volume.
Since the vapor space at 105°F would be greater than 1.00%, the car is not overloaded by volume.
Overload check by weight:
1. Compare cargo weight calculated above to Load Limit weight. 135,672 pounds is less than 190,300 pounds, or
2. Add Tare weight to cargo weight calculated above and compare to statutory limit:
72,700 + 135,672 = 208,372 pounds, which is less than 263,000 pounds.
Thus, the car is not overloaded by weight.
If CTS is not included, NSV is 22,581 gallons, W is 135,672 pounds, and the vapor space % is 1.29%.
F.10 Example 9: Outage Vapor Capacity Table — Actual Loaded Calculation — Overstated Target
Loading Temperature Results in Overloading by Volume
A general purpose car is loaded with Light Cat Cracked Gasoline close to the target outage determined in
Example 6, but at a colder temperature (90°F) than that used in the target calculation (95°F).
Tank Car Data
Product Data
Tare:
72,700 pounds
Loaded Temperature:
90°F
Load Limit:
190,300 pounds
Manway Nozzle Height:
9.25 in.
Stenciled Volume:
23,639 gallons
CTL Table (API gravity):
API 6B (65.0)
Capacity Table:
Table F-2
Density at Reference Temp:
6.004 pounds / gallon
Insulated?
Yes
Outage Gauge (from top of manway):
13.500 in.
Vtblmax
23,679 gallons
Statutory Temp:
105°F
CTS90
1.00056 (Equat. B-1)
MFLA
0.99
CTLstat
0.96772
CTL90
0.97854
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
%S&W
37
0.0%
Net Standard Volume is determined with equation (5).
GOVtbl:
The capacity table (Table E-2) does not include a nozzle height, so one must first subtract the manway nozzle
height from the outage gauge:
13.500 in. – 9.500 in. = 4.000 in.
Since the capacity table is an Outage Vapor table in quarter-inch increments, one need not interpolate for 4.000
inches, but must subtract the corresponding vapor volume from the table maximum volume. The resulting liquid
volume is:
(23,679 – 412) = 23,267 gallons
NSV
= GOVtbl (CTAF) (CTL90) (CTS90)
= (23,267) (23,639 / 23,679) (0.97854) (1.00056)
= 22,742 gallons
The cargo’s weight is determined with equation (3):
W = NSV (dref) = 22,742 (6.004) = 136,543 pounds
Overload check by volume, using equations (8) and (9):
MFLL = (GOVtbl) (CTAF) (CTL90) (CTS90)
(CTSstat) (CTLstat) (Vs)
= (23,267) (23,639 / 23,679) (0.97854) (1.00056)
(1.00084) (0.96772) (23,639)
= 0.9933%
Vapor Space % = 100 – 0.9933 * 100 = 0.67%
Since the loaded liquid fraction at 105°F would be more than 0.9900 the car is overloaded by volume; or, since
the vapor space at 105°F would be less than 1.00%, the car is overloaded by volume by:
NSV = (Vs) (0.19%) (CTLstat) (CTSstat)
= (23,639) (0.0019) (0.96772) (1.00084)
= 44 net gallons
Overload check by weight:
1. Compare cargo weight calculated above to Load Limit weight. 136,357 pounds is less than 190,300 pounds, or
2. Add Tare weight to cargo weight calculated above and compare to statutory limit:
72,700 + 136,357 = 209,057 pounds, which is less than 263,000 pounds.
Thus, the car is not overloaded by weight.
38
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
F.11 Example 10: Outage Vapor Capacity Table — Pressure Car Target Loading Calculation —
Summer Loading
A pressure car is to be loaded with Propane in the summer.
Tank Car Data
Product Data
Tare:
100,800 pounds
Estimated Loading Temperature:
92°F
Load Limit:
162,200 pounds
Manway Nozzle Height:
0.00 in.
Stenciled Volume:
33,648 gallons
CTL Table (relative density):
API Chapt 11.2.4 (0.5059)
Capacity Table:
Table F-4
Density at Reference Temp:
4.218 pounds/gallon
Insulated?
No
Statutory Temp:
115°F
Vtblmax
33,653 gallons
MFLA
0.99
CTSstat
1.00102 (Equat. B-1)
CTLstat
0.89963 (Chapt 11.2.4)
CTS92
1.00060 (Equat. B-1)
CTL92
0.94460 (Chapt 11.2.4)
CPSstat
1.00131 (Equat. C-1)
Pressure @ 92°F
165 psig
CPS92
1.00096 (Equat. C-1)
Pressure @ 115°F
226 psig (Chapt 11.2.5)
The weight corresponding to the statutory volume limitation must be calculated using equation (A.5).
Wma
= Vs (MFLA) (CTLstat) (CPLstat) (CTSstat) (CPSstat) (dref)
= (33,648) (0.99) (0.89963) (1.00000) (1.00102) (1.00131) (4.218)
= 126,701 pounds
Since this is less than the Load Limit, the car can be loaded to statutory volume limits. If the Load Limit is not
available, add Wma to the Tare (100,800 + 126,701 = 227,501) and compare with the weight limitation for that
particular car (263,000 pounds for this car).
One must now determine the target outage (liquid level) derived from the statutory volume using equation (A.7).
GOV
= Vtblmax (MFLA) (CTLstat) (CPLstat) (CTSstat) (CPSstat)
(CTL92) (CPL92) (CTS92) (CPS92)
= (33,653) (0.99) (0.89963) (1.00000) (1.00102) (1.00131)
(0.94460) (1.00000) (1.00060) (1.00096)
= 31,755 gallons
Since the capacity table is an Outage Vapor, the volumes listed are vapor volumes. To convert GOV to its
corresponding vapor volume, subtract GOV from the maximum vapor volume in the table:
33,653 – 31,755 = 1,898 gallons vapor
Looking up this volume in the capacity table, it falls between volumes representing 12.75 inches and 13.00 inches
Interpolating to the nearest 1/8 inch, 12.875 inches is equal to:
(1,892 – 1,947) / 2 + 1,947 = 1,920 gallons
Since the vapor space corresponding to the GOV is less than the vapor volume corresponding to 12.875 inches,
we round to the outage corresponding to the larger vapor volume, 12.875 inches, and load to 1920 gallons of
vapor. We do not round up to the outage corresponding to a smaller vapor volume (12.75 inches). If we wish to
measure only to the nearest 0.250 inch, we would choose 13.000 inches without bothering to interpolate.
Because this is a pressure car, the product level is measured by an internal gauge, and the manway height is not
needed.
If corrections for the optional shell expansion due to temperature and pressure are omitted, Wma equals 126,405
lb and GOV will be 31,730 liquid gallons, or 1923 vapor gallons, resulting in a loading outage of 13.000 inches.
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
39
F.12 Example 11: Outage Vapor Capacity Table — Pressure Car Target Loading Calculation —
Winter Loading
The pressure car in Example 10 is to be loaded with propane under winter regulations.
Tank Car Data
Product Data
Tare:
100,800 pounds
Estimated Loading Temperature:
92°F
Load Limit:
162,200 pounds
Manway Nozzle Height:
0.00 in.
Stenciled Volume:
33,648 gallons
CTL Table (relative density):
API Chapt 11.2.4 (0.5059)
Capacity Table:
Table F-4
Density at Reference Temp:
4.218 pounds/gallon
Insulated?
No
Statutory Temp:
100°F
Vtblmax
33,653 gallons
MFLA
0.99
CTSstat
1.00074 (Equat. B-1)
CTLstat
0.92955 (Chapt 11.2.4)
CTS92
1.00060 (Equat. B-1)
CTL92
0.94460 (Chapt 11.2.4)
CPSstat
1.00108 (Equat. C-1)
Pressure @ 92°F
165 psig
CPS92
1.00096 (Equat. C-1)
Pressure @ 100°F
185 psig (Chapt 11.2.5)
The weight corresponding to the statutory volume limitation must be calculated using equation (A.5).
Wma
= Vs (MFLA) (CTLstat) (CPLstat) (CTSstat) (CPSstat) (dref)
= (33,648) (0.99) (0.92955) (1.00000) (1.00074) (1.00108) (4.218)
= 130,847 pounds
Since this is less than the Load Limit, the car can be loaded to statutory volume limits. If the Load Limit is not
available, add Wma to the Tare (100,800 + 130,847 = 231,647) and compare with the weight limitation for that
particular car (263,000 pounds for this car).
One must now determine the target outage (liquid level) derived from the statutory volume using equation (A.7).
GOV
= Vtblmax (MFLA) (CTLstat) (CPLstat) (CTSstat) (CPSstat)
(CTL92) (CPL92) (CTS92) (CPS92)
= (33,653 (0.99) (0.92955) (1.00000) (1.00074) (1.00108)
(0.94460) (1.00000) (1.00060) (1.00096)
= 32,794 gallons
Since the capacity table is an Outage Vapor, the volumes listed are vapor volumes. To convert GOV to its
corresponding vapor volume, subtract GOV from the maximum vapor volume in the table:
33,653 – 32,794 = 859 gallons vapor
Looking up this volume in the capacity table, it falls between volumes representing 7.250 inches and 7.500
inches. Interpolating to the nearest 1/8 inch, 7.375 inches is equal to:
(819 – 861) / 2 + 861 = 840 gallons
Since the vapor space corresponding to the GOV is more than the volume corresponding to 7.375 inches, but less
than that for 7.500 inches, we round to the outage corresponding to the larger vapor volume, 7.500 inches, and
load to 861 gallons of vapor. We do not round up to the outage corresponding to a smaller vapor volume (7.375
inches). If we wish to measure only to the nearest 0.250 inch, we would choose 7.500 inches. Since this is a
pressure car, the product level is measured by an internal gauge, and the manway height is not needed or used.
Comparing this result to Example 10, we can load 1,059 gallons (1920 – 861) more product at 92°F (or 1002
gallons net) under winter regulations than under summer regulations.
If corrections for the optional shell expansion due to temperature and pressure are omitted, Wma will be 130,609
lb and GOV 32,786 gallons, corresponding to an outage of 7.500 in.
40
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
F.13 Example 12: Outage Vapor Capacity Table — Pressure Car Actual Loaded Calculation
A pressure car is loaded with Propane in the summer close to the Target outage determined in Example 10.
Tank Car Data
Product Data
Tare:
100,800 pounds
Estimated Loading Temperature:
95°F
Load Limit:
162,200 pounds
Manway Nozzle Height:
0.00 in.
Stenciled Volume:
33,648 gallons
CTL Table (relative density):
API Chapt 11.2.4 (0.5059)
Capacity Table:
Table F-4
Density at Reference Temp:
4.218 pounds/gallon
Insulated?
No
Statutory Temp:
115°F
Vtblmax
33,653 gallons
MFLA
0.99
CTSstat
1.00102 (Equat. B-1)
Outage Gauge (internal):
13.000 in.
CTS95
1.00065 (Equat. B-1)
CTLstat
0.89963 (Chapt 11.2.4)
CPSstat
1.00131 (Equat. C-1)
CTL95
0.93903 (Chapt 11.2.4)
CPS95
1.00100 (Equat. C-1)
Pressure @ 95°F
172 psig
Pressure @ 115°F
226 psig (Chapt 11.2.5)
Net Standard Volume is determined with equation (6).
GOVtbl: The capacity table (Table E-4) does not include a nozzle height, but since the internal gauge measures from the
top inside of the car’s shell, no correction is needed and the outage can be looked up directly in the car’s
capacity table.
Since the capacity table is an Outage Vapor table in quarter inch increments, one need not interpolate
for 13.000 inches but must subtract the corresponding vapor volume from the table maximum
volume. The resulting liquid volume is:
(33,653 – 1,947) = 31,706 gallons
NSV
= (GOVtbl) (CTAF) (CTL92) (CTS92) (CPS92)
= (31,706) (33,648 / 33,653) (0.93903) (1.00065) (1.00100)
= 29,788 gallons
The cargo’s weight is determined with equation (2):
W = (NSV) (dref) = 29,788 (4.218) = 125,646 pounds
Overload check by volume, using equation (8) and (9):
MFLL = (GOVtbl) (CTAF) (CTL) (CTS) (CPS)
(CTSstat) (CTLstat) (CPSstat) (Vs)
= (31,706) (33,648 / 33,653) (0.93903) (1.00065) (1.00100)
(1.00102) (0.89963) (1.00131) (33,648)
= 0.9840
Vapor Space % = 100 – 0.9840 * 100 = 1.60%
Since the MFLL is less than 0.99 and the corresponding vapor space at 115°F is more than 1.00%, the car is not
overloaded by volume.
Overload check by weight:
1. Compare cargo weight calculated above to Load Limit weight. 125,960 pounds is less than 162,200 pounds, or
2. Add Tare weight to cargo weight calculated above, and compare to statutory limit:
100,800 + 125,646 = 226,361 pounds, which is less than 263,000 pounds.
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
41
Thus, the car is not overloaded by weight.
If corrections for the optional shell expansion due to temperature and pressure are omitted, NSV will be 29,768
gallons, the MFLL 0.9834, and the % vapor space 1.66%.
F.14 Example 13: Innage Liquid Capacity Table — Loading Target Calculation — Volume
Limitation
A general purpose car is to be loaded with p-Xylene.
Tank Car Data
Product Data
Tare:
65,900 pounds
Estimated Loading Temperature:
75°F
Load Limit:
197,100 pounds
Manway Nozzle Height:
13.375 in.
Stenciled Volume:
26,859 gallons
CTL Table:
ASTM D1555
Capacity Table:
Table F-5
Density at Reference Temp:
7.2151 pounds / gallon
Insulated?
No
Statutory Temp:
115°F
Vtblmax
26,838 gallons
MFLA
0.99
CTSstat
1.00102 (Equat. B-1)
CTLstat
0.96942
D1555)
(ASTM
CTS75
1.00028 (Equat. B-1)
CTL75
0.99174
D1555)
(ASTM
The weight corresponding to the statutory volume limitation must be calculated using equation (A.1).
Wma
= Vs (MFLA) (CTLstat) (CTSstat) (dref)
= (26,859) (0.99) (0.96942) (1.00102) (7.2151)
= 186,175 pounds
Since this is less than the Load Limit, the car can be loaded to statutory volume limits. If the Load Limit is not
available, add Wma to the Tare (65,900 + 186,175 = 252,075) and compare with the weight limitation for that
particular car (263,000 pounds for this car).
One must now determine the target outage (liquid level) derived from the statutory volume using equation (A.3).
GOV
= Vtblmax (MFLA) (CTLstat) (CTSstat)
(CTL75) (CTS75)
= (26,838) (0.99) (0.96942) (1.00102)
(0.99174) (1.00028)
= 25, 991 gallons
Since the capacity table is an Innage Liquid, the volumes listed are liquid volumes. Looking up this volume in the
capacity table, it falls between volumes representing 101.250 inches and 101.500 inches. Interpolating to the
nearest 1/8 inch, 101.375 inches is equal to:
(25,975 – 26,018) / 2 + 25,975 = 25,997 gallons
Since GOV is greater than the volume corresponding to 101.250 inches, but less than that corresponding to
101.375 inches, we round to the innage corresponding to a smaller liquid volume, 101.250 inches. We do not
round up to the innage corresponding to a larger liquid volume (101.375 inches). If we wish to measure only to
the nearest 1/4 inch, we would choose 101.250 inches.
Since this is an innage table, we do not need the manway nozzle height if we are going to perform an innage
measurement. If measuring from the top of the manway, we must add the manway nozzle height to the shell
diameter (maximum value in the table), and subtract the above calculated innage to get the target outage:
108.75 in. + 13.375 in. – 101.25 in. = 20.875 in.
If measuring from the top inside of the shell, the outage would be:
42
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
108.750 in. – 101.250 in. = 7.500 in.
If corrections for the optional shell expansion due to temperature are omitted, Wma = 185,986 lb (well within the load
limit), and GOV = 25,972 gal, corresponding to an innage of 101.125 inches or , if rounding to the nearest quarter
inch, 101 inches.
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
43
Table F-1 — Tank Car Capacity Table
Tank Car:
ACFX 75538
Capacity Table: ACF 1785
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
3.25
3.50
3.75
4.00
4.25
4.50
4.75
5.00
5.25
5.50
5.75
6.00
6.25
6.50
6.75
7.00
7.25
7.50
7.75
8.00
8.25
8.50
8.75
9.00
9.25
9.50
9.75
10.00
10.25
10.50
10.75
11.00
11.25
11.50
11.75
30,154
30,151
30,145
30,137
30,125
30,111
30,095
30,076
30,055
30,032
30,008
29,982
29,955
29,927
29,898
29,868
29,838
29,807
29,777
29,746
29,715
29,685
29,656
29,627
29,597
29,564
29,529
29,493
29,455
29,416
29,375
29,334
29,292
29,250
29,208
29,167
29,125
29,085
29,043
29,002
28,960
28,918
28,875
28,832
28,788
28,744
28,699
28,654
12.00
12.25
12.50
12.75
13.00
13.25
13.50
13.75
14.00
14.25
14.50
14.75
15.00
15.25
15.50
15.75
16.00
16.25
16.50
16.75
17.00
17.25
17.50
17.75
18.00
18.25
18.50
18.75
19.00
19.25
19.50
19.75
20.00
20.25
20.50
20.75
21.00
21.25
21.50
21.75
22.00
22.25
22.50
22.75
23.00
23.25
23.50
23.75
28,608
28,561
28,514
28,465
28,416
28,366
28,316
28,265
28,213
28,162
28,110
28,058
28,006
27,953
27,900
27,846
27,792
27,738
27,683
27,628
27,572
27,516
27,460
27,403
27,346
27,288
27,230
27,172
27,113
27,054
26,995
26,934
26,874
26,813
26,752
26,690
26,628
26,567
26,505
26,442
26,380
26,318
26,255
26,192
26,128
26,065
26,001
25,937
Nozzle Volume: 0
Nozzle Height: 12.5
24.00
24.25
24.50
24.75
25.00
25.25
25.50
25.75
26.00
26.25
26.50
26.75
27.00
27.25
27.50
27.75
28.00
28.25
28.50
28.75
29.00
29.25
29.50
29.75
30.00
30.25
30.50
30.75
31.00
31.25
31.50
31.75
32.00
32.25
32.50
32.75
33.00
33.25
33.50
33.75
34.00
34.25
34.50
34.75
35.00
35.25
35.50
35.75
25,873
25,808
25,744
25,679
25,613
25,548
25,482
25,416
25,350
25,283
25,216
25,149
25,082
25,014
24,946
24,878
24,809
24,739
24,670
24,600
24,531
24,461
24,392
24,323
24,255
24,186
24,117
24,047
23,978
23,907
23,837
23,766
23,695
23,623
23,551
23,479
23,406
23,333
23,259
23,185
23,111
23,036
22,962
22,887
22,813
22,740
22,667
22,593
36.00
36.25
36.50
36.75
37.00
37.25
37.50
37.75
38.00
38.25
38.50
38.75
39.00
39.25
39.50
39.75
40.00
40.25
40.50
40.75
41.00
41.25
41.50
41.75
42.00
42.25
42.50
42.75
43.00
43.25
43.50
43.75
44.00
44.25
44.50
44.75
45.00
45.25
45.50
45.75
46.00
46.25
46.50
46.75
47.00
47.25
47.50
47.75
22,519
22,444
22,368
22,291
22,214
22,137
22,060
21,983
21,906
21,829
21,753
21,676
21,599
21,522
21,445
21,368
21,291
21,213
21,136
21,059
20,982
20,905
20,827
20,750
20,672
20,595
20,517
20,440
20,362
20,284
20,206
20,128
20,050
19,971
19,893
19,815
19,736
19,657
19,578
19,499
19,420
19,341
19,261
19,182
19,102
19,023
18,943
18,863
48.00
48.25
48.50
48.75
49.00
49.25
49.50
49.75
50.00
50.25
50.50
50.75
51.00
51.25
51.50
51.75
52.00
52.25
52.50
52.75
53.00
53.25
53.50
53.75
54.00
54.25
54.50
54.75
55.00
55.25
55.50
55.75
56.00
56.25
56.50
56.75
57.00
57.25
57.50
57.75
58.00
58.25
58.50
58.75
59.00
59.25
59.50
59.75
Stencil Volume:
Nozzle Height Included?
18,783
18,702
18,622
18,542
18,461
18,380
18,300
18,219
18,138
18,057
17,976
17,895
17,814
17,733
17,652
17,570
17,489
17,408
17,326
17,245
17,163
17,082
17,000
16,919
16,837
16,755
16,674
16,592
16,510
16,429
16,347
16,265
16,182
16,100
16,018
15,935
15,852
15,770
15,687
15,604
15,521
15,438
15,355
15,272
15,189
15,106
15,023
14,940
60.00
60.25
60.50
60.75
61.00
61.25
61.50
61.75
62.00
62.25
62.50
62.75
63.00
63.25
63.50
63.75
64.00
64.25
64.50
64.75
65.00
65.25
65.50
65.75
66.00
66.25
66.50
66.75
67.00
67.25
67.50
67.75
68.00
68.25
68.50
68.75
69.00
69.25
69.50
69.75
70.00
70.25
70.50
70.75
71.00
71.25
71.50
71.75
14,857
14,774
14,691
14,608
14,526
14,443
14,360
14,278
14,195
14,113
14,031
13,949
13,867
13,785
13,704
13,622
13,541
13,460
13,379
13,298
13,217
13,136
13,055
12,974
12,893
12,813
12,732
12,652
12,571
12,491
12,411
12,330
12,250
12,170
12,090
12,010
11,930
11,850
11,770
11,690
11,611
11,531
11,451
11,372
11,292
11,213
11,133
11,054
72.00
72.25
72.50
72.75
73.00
73.25
73.50
73.75
74.00
74.25
74.50
74.75
75.00
75.25
75.50
75.75
76.00
76.25
76.50
76.75
77.00
77.25
77.50
77.75
78.00
78.25
78.50
78.75
79.00
79.25
79.50
79.75
80.00
80.25
80.50
80.75
81.00
81.25
81.50
81.75
82.00
82.25
82.50
82.75
83.00
83.25
83.50
83.75
30168
No
10,975
10,895
10,816
10,737
10,658
10,579
10,500
10,421
10,343
10,264
10,185
10,107
10,028
9,950
9,871
9,793
9,715
9,636
9,558
9,430
9,402
9,324
9,246
9,168
9,090
9,012
8,934
8,857
8,779
8,701
8,624
8,546
8,468
8,391
8,313
8,235
8,158
8,080
8,003
7,925
7,848
7,770
7,696
7,621
7,548
7,475
7,402
7,328
Tare: 67900
Type: Outage Liquid
84.00
84.25
84.50
84.75
85.00
85.25
85.50
85.75
86.00
86.25
86.50
86.75
87.00
87.25
87.50
87.75
88.00
88.25
88.50
88.75
89.00
89.25
89.50
89.75
90.00
90.25
90.50
90.75
91.00
91.25
91.50
91.75
92.00
92.25
92.50
92.75
93.00
93.25
93.50
93.75
94.00
94.25
94.50
94.75
95.00
95.25
95.50
95.75
7,254
7,179
7,105
7,030
6,956
6,882
6,809
6,736
6,664
6,593
6,521
6,450
6,379
6,308
6,226
6,164
6,092
6,020
5,948
5,877
5,806
5,735
5,665
5,595
5,526
5,456
5,388
5,319
5,251
5,183
5,115
5,048
4,981
4,914
4,847
4,781
4,715
4,649
4,584
4,518
4,453
4,385
4,324
4,260
4,196
4,132
4,069
4,005
96.00
96.25
96.50
96.75
97.00
97.25
97.50
97.75
98.00
98.25
98.50
98.75
99.00
99.25
99.50
99.75
100.00
100.25
100.50
100.75
101.00
101.25
101.50
101.75
102.00
102.25
102.50
102.75
103.00
103.25
103.50
103.75
104.00
104.25
104.50
104.75
105.00
105.25
105.50
105.75
106.00
106.25
106.50
106.75
107.00
107.25
107.50
107.75
3,942
3,879
3,817
3,754
3,692
3,630
3,568
3,507
3,445
3,384
3,323
3,262
3,202
3,143
3,084
3,025
2,967
2,909
2,852
2,794
2,738
2,681
2,625
2,565
2,513
2,458
2,403
2,349
2,294
2,240
2,187
2,133
2,080
2,027
1,974
1,921
1,869
1,817
1,765
1,714
1,663
1,613
1,564
1,514
1,465
1,416
1,368
1,320
108.00
108.25
108.50
108.75
109.00
109.25
109.50
109.75
110.00
110.25
110.50
110.75
111.00
111.25
111.50
111.75
112.00
112.25
112.50
112.75
113.00
113.25
113.50
113.75
114.00
114.25
114.5
114.75
115.00
115.25
115.50
115.75
116.00
116.25
116.50
116.75
117.00
117.25
117.50
117.75
118.00
118.25
118.50
1,272
1,226
1,180
1,136
1,093
1,051
1,008
966
925
884
844
805
766
728
696
656
621
587
555
524
493
462
433
404
375
347
319
292
265
239
212
187
161
136
111
87
62
38
20
9
3
1
0
44
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Table F-2 — Tank Car Capacity Table
Tank Car:
GATX 3741
Capacity Table: GAT 8582
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
3.25
3.50
3.75
4.00
4.25
4.50
4.75
5.00
5.25
5.50
5.75
6.00
6.25
6.50
6.75
7.00
7.25
7.50
7.75
8.00
8.25
8.50
8.75
9.00
9.25
9.50
9.75
10.00
10.50
11.00
11.50
12.00
12.50
13.00
13.50
14.00
14.50
15.00
15.50
16.00
16.50
17.00
17.50
18.00
18.50
19.00
19.50
19
40
61
83
107
131
156
182
208
235
263
291
321
350
381
412
444
476
509
542
576
611
646
682
718
755
792
829
867
906
945
984
1,024
1,064
1,105
1,146
1,188
1,230
1,272
1,315
1,402
1,490
1,580
1,671
1,764
1,857
1,953
2,050
2,147
2,247
2,347
2,448
2,551
2,655
2,760
2,866
2,973
3,081
3,191
Nozzle Volume: 0
Nozzle Height: 9.5
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
3,301
3,524
3,751
3,981
4,215
4,452
4,692
4,935
5,181
5,430
5,681
5,934
6,190
6,448
6,707
6,969
7,233
7,498
7,765
8,033
8,303
8,574
8,846
9,119
9,394
9,669
9,944
10,221
10,498
10,775
11,053
11,331
11,609
11,887
12,165
12,443
12,721
12,998
13,275
13,552
13,827
14,102
14,376
14,650
14,922
15,193
15,463
15,731
15,998
16,263
16,527
16,789
17,049
17,307
17,563
17,816
18,067
18,316
18,562
Stencil Volume:
Nozzle Height Included?
79.00
80.00
81.00
82.00
83.00
84.00
85.00
86.00
87.00
88.00
89.00
90.00
91.00
91.50
92.00
92.50
93.00
93.50
94.00
94.50
95.00
95.50
96.00
96.50
97.00
97.50
98.00
98.50
99.00
99.50
100.00
100.50
100.75
101.00
101.25
101.50
101.75
102.00
102.25
102.50
102.75
103.00
103.25
103.50
103.75
104.00
104.25
104.50
104.75
105.00
105.25
105.50
105.75
106.00
106.25
106.50
106.75
107.00
107.25
18,805
19,045
19,282
19,516
19,747
19,974
20,197
20,416
20,632
20,843
21,050
21,252
21,449
21,546
21,642
21,736
21,829
21,920
22,010
22,098
22,185
22,271
22,354
22,436
22,517
22,595
22,672
22,747
22,820
22,891
22,960
23,027
23,059
23,091
23,123
23,154
23,184
23,213
23,242
23,270
23,298
23,325
23,351
23,376
23,401
23,425
23,448
23,470
23,491
23,511
23,530
23,548
23,564
23,579
23,593
23,606
23,618
23,628
23,637
23639
No
Tare: 72700
Type: Outage Vapor
107.50
107.75
108.00
108.25
108.50
108.75
109.00
109.25
109.50
109.75
110.25
23,645
23,652
23,658
23,664
23,668
23,671
23,674
23,676
23,677
23,678
23,679
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
45
Table F-3 — Tank Car Capacity Table
Tank Car:
SCMX 2197 1
Capacity Table: SCM 922197
12.50
12.75
13.00
13.25
13.50
13.75
14.00
14.25
14.50
14.75
15.00
15.25
15.50
15.75
16.00
16.25
16.50
16.75
17.00
17.25
17.50
17.75
18.00
18.25
18.50
18.75
19.00
19.25
19.50
19.75
20.00
20.25
20.50
20.75
21.00
21.25
21.50
21.75
22.00
22.25
22.50
22.75
23.00
23.25
23.50
23.75
24.00
24.25
24.50
24.75
25.00
25.25
25.50
25.75
26.00
26.25
26.50
26.75
27.00
27.25
27.50
27.75
28.00
28.25
11,348
11,345
11,342
11,336
11,329
11,323
11,317
11,307
11,297
11,287
11,277
11,267
11,256
11,245
11,234
11,222
11,210
11,197
11,183
11,170
11,157
11,143
11,130
11,117
11,100
11,083
11,067
11,050
11,033
11,017
10,998
10,980
10,962
10,944
10,925
10,907
10,889
10,871
10,853
10,834
10,816
10,795
10,773
10,752
10,730
10,709
10,687
10,666
10,645
10,623
10,602
10,580
10,559
10,537
10,516
10,493
10,470
10,446
10,423
10,400
10,377
10,354
10,331
10,308
28.50
28.75
29.00
29.25
29.50
29.75
30.00
30.25
30.50
30.75
31.00
31.25
31.50
31.75
32.00
32.25
32.50
32.75
33.00
33.25
33.50
33.75
34.00
34.25
34.50
34.75
35.00
35.25
35.50
35.75
36.00
36.25
36.50
36.75
37.00
37.25
37.50
37.75
38.00
38.25
38.50
38.75
39.00
39.25
39.50
39.75
40.00
40.25
40.50
40.75
41.00
41.25
41.50
41.75
42.00
42.25
42.50
42.75
43.00
43.25
43.50
43.75
44.00
44.25
Nozzle Volume: 0
Nozzle Height: 12.5
10,285
10,262
10,238
10,215
10,189
10,162
10,135
10,108
10,082
10,055
10,028
10,002
9,975
9,948
9,922
9,895
9,868
9,841
9,815
9,787
9,759
9,732
9,704
9,677
9,649
9,621
9,594
9,566
9,538
9,511
9,483
9,456
9,428
9,399
9,370
9,340
9,310
9,281
9,251
9,221
9,192
9,162
9,132
9,103
9,073
9,043
9,014
8,982
8,951
8,920
8,888
8,857
8,826
8,794
8,763
8,732
8,701
8,669
8,638
8,607
8,575
8,544
8,513
8,480
44.50
44.75
45.00
45.20
45.50
45.75
46.00
46.25
46.50
46.75
47.00
47.25
47.50
47.75
48.00
48.25
48.50
48.75
49.00
49.25
49.50
49.75
50.00
50.25
50.50
50.75
51.00
51.25
51.50
51.75
52.00
52.25
52.50
52.75
53.00
53.25
53.50
53.75
54.00
54.25
54.50
54.75
55.00
55.25
55.50
55.75
56.00
56.25
56.50
56.75
57.00
57.25
57.50
57.75
58.00
58.25
58.50
58.75
59.00
59.25
59.50
59.75
60.00
60.25
8,448
8,416
8,384
8,351
8,319
8,287
8,254
8,222
8,190
8,157
8,125
8,093
8,060
8,028
7,995
7,962
7,929
7,895
7,862
7,828
7,795
7,762
7,728
7,695
7,661
7,628
7,595
7,561
7,528
7,494
7,459
7,425
7,390
7,356
7,321
7,287
7,252
7,218
7,183
7,149
7,114
7,080
7,045
7,011
6,976
6,941
6,907
6,872
6,838
6,803
6,769
6,734
6,700
6,665
6,631
6,596
6,562
6,527
6,492
6,458
6,423
6,389
6,354
6,320
Stencil Volume:
Nozzle Height Included?
60.50
60.75
61.00
61.25
61.50
61.75
62.00
62.25
62.50
62.75
63.00
63.25
63.50
63.75
64.00
64.25
64.50
64.75
65.00
65.25
65.50
65.75
66.00
66.25
66.50
66.75
67.00
67.25
67.50
67.75
68.00
68.25
68.50
68.75
69.00
69.25
69.50
69.75
70.00
70.25
70.50
70.75
71.00
71.25
71.50
71.75
72.00
72.25
72.50
72.75
73.00
73.25
73.50
73.75
74.00
74.25
74.50
74.75
75.00
75.25
75.50
75.75
76.00
76.25
6,285
6,251
6,216
6,182
6,147
6,113
6,078
6,044
6,009
5,973
5,937
5,902
5,866
5,830
5,794
5,759
5,723
5,687
5,651
5,616
5,580
5,544
5,508
5,472
5,437
5,401
5,365
5,329
5,294
5,258
5,222
5,186
5,151
5,115
5,079
5,043
5,008
4,973
4,938
4,904
4,869
4,835
4,800
4,766
4,731
4,697
4,662
4,628
4,593
4,559
4,524
4,490
4,456
4,422
4,388
4,354
4,320
4,286
4,252
4,218
4,184
4,150
4,116
4,082
76.50
76.75
77.00
77.25
77.50
77.75
78.00
78.25
78.50
78.75
79.00
79.25
79.50
79.75
80.00
80.25
80.50
80.75
81.00
81.25
81.50
81.75
82.00
82.25
82.50
82.75
83.00
83.25
83.50
83.75
84.00
84.25
84.50
84.75
85.00
85.25
85.50
85.75
86.00
86.25
86.50
86.75
87.00
87.25
87.50
87.75
88.00
88.25
88.50
88.75
89.00
89.25
89.50
89.75
90.00
90.25
90.50
90.75
91.00
91.25
91.50
91.75
92.00
92.25
4,048
4,014
3,981
3,947
3,913
3,879
3,845
3,811
3,777
3,743
3,709
3,675
3,641
3,607
3,573
3,539
3,505
3,474
3,443
3,411
3,380
3,349
3,317
3,286
3,255
3,224
3,192
3,161
3,130
3,098
3,067
3,036
3,005
2,974
2,943
2,912
2,881
2,850
2,820
2,789
2,758
2,727
2,696
26,66
2,635
2,604
2,573
2,542
2,511
2,481
2,450
2,419
2,388
2,357
2,327
2,296
2,265
2,234
2,203
2,174
2,144
2,114
2,085
2,055
11348
Yes
92.50
92.75
93.00
93.25
93.50
93.75
94.00
94.25
94.50
94.75
95.00
95.25
95.50
95.75
96.00
96.25
96.50
96.75
97.00
97.25
97.50
97.75
98.00
98.25
98.50
98.75
99.00
99.25
99.50
99.75
100.00
100.25
100.50
100.75
101.00
101.25
101.50
101.75
102.00
102.25
102.50
102.75
103.00
103.25
103.50
103.75
104.00
104.25
104.50
104.75
105.00
105.25
105.50
105.75
106.00
106.25
106.50
106.75
107.00
107.25
107.50
107.75
108.00
108.25
Tare: 67200
Type: Outage Liquid
2,025
1,996
1,966
1,936
1,907
1,877
1,847
1,818
1,789
1,761
1,734
1,706
1,678
1,651
1,623
1,595
1,568
1,540
1,513
1,485
1,457
1,430
1,402
1,378
1,354
1,329
1,305
1,281
1,256
1,232
1,208
1,184
1,159
1,135
1,111
1,086
1,062
1,038
1,014
990
966
943
919
895
872
848
825
801
781
761
741
721
701
681
661
641
621
601
582
563
544
525
506
486
108.500
108.750
109.000
109.250
109.500
109.750
110.000
110.250
110.500
110.750
111.000
111.250
111.500
111.750
112.000
112.250
112.500
112.750
113.000
113.250
113.500
113.750
114.000
114.250
114.500
114.750
115.000
115.250
115.500
115.750
116.000
116.250
116.500
116.750
117.000
117.250
117.500
117.750
118.000
118.250
118.500
118.750
119.000
119.250
119.500
119.750
120.000
120.625
467
448
429
410
393
377
362
347
331
316
300
285
270
254
239
223
208
194
182
169
156
144
131
119
106
96
88
79
71
63
54
48
43
39
34
30
26
21
17
12
9
8
6
5
4
2
1
0
46
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Table F-4 — Tank Car Capacity Table
Tank Car:
Capacity Table:
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
3.25
3.50
3.75
4.00
4.25
4.50
4.75
5.00
5.25
5.50
5.75
6.00
6.25
6.50
6.75
7.00
7.25
7.50
7.75
8.00
8.25
8.50
8.75
9.00
9.25
9.50
9.75
10.00
10.25
10.50
10.75
11.00
11.25
11.50
11.75
12.00
12.25
GATX 40671
GAT 6895
3
8
18
30
45
61
80
100
121
144
169
194
221
248
277
307
338
370
403
436
471
506
543
580
618
656
696
736
777
819
861
904
948
992
1,037
1,083
1,129
1,176
1,223
1,272
1,320
1,369
1,419
1,470
1,521
1,572
1,624
1,677
1,730
1,783
12.50
12.75
13.00
13.25
13.50
13.75
14.00
14.25
14.50
14.75
15.00
15.25
15.50
15.75
16.00
16.25
16.50
16.75
17.00
17.25
17.50
17.75
18.00
18.25
18.50
18.75
19.00
19.25
19.50
19.75
20.00
20.25
20.50
20.75
21.00
21.25
21.50
21.75
22.00
22.25
22.50
22.75
23.00
23.25
23.50
23.75
24.00
24.25
24.50
24.75
Nozzle Volume: 0
Nozzle Height: 0
1,837
1,892
1,947
2,002
2,058
2,115
2,172
2,229
2,287
2,346
2,404
2,464
2,523
2,583
2,644
2,705
2,766
2,828
2,890
2,953
3,016
3,079
3,143
3,207
3,271
3,336
3,401
3,467
3,533
3,599
3,666
3,733
3,800
3,868
3,936
4,005
4,073
4,142
4,212
4,281
4,352
4,422
4,492
4,563
4,635
4,706
4,778
4,850
4,923
4,995
25.00
25.25
25.50
25.75
26.00
26.25
26.50
26.75
27.00
27.25
27.50
27.75
28.00
28.25
28.50
28.75
29.00
29.25
29.50
29.75
30.00
30.25
30.50
30.75
31.00
31.25
31.50
31.75
32.00
32.25
32.50
32.75
33.00
33.25
33.50
33.75
34.00
34.25
34.50
34.75
35.00
35.25
35.50
35.75
36.00
36.25
36.50
36.75
37.00
37.25
Stencil Volume:
Nozzle Height Included?
5,068
5,142
5,215
5,289
5,363
5,438
5,512
5,587
5,663
5,738
5,814
5,890
5,966
6,043
6,119
6,196
6,273
6,351
6,429
6,506
6,585
6,663
6,742
6,820
6,900
6,979
7,058
7,138
7,218
7,298
7,378
7,459
7,540
7,621
7,702
7,783
7,865
7,946
8,028
8,110
8,193
8,275
8,358
8,440
8,523
8,607
8,690
8,773
8,857
8,941
37.50
37.75
38.00
38.25
38.50
38.75
39.00
39.25
39.50
39.75
40.00
40.25
40.50
40.75
41.00
41.25
41.50
41.75
42.00
42.25
42.50
42.75
43.00
43.25
43.50
43.75
44.00
44.25
44.50
44.75
45.00
45.25
45.50
45.75
46.00
46.25
46.50
46.75
47.00
47.25
47.50
47.75
48.00
48.25
48.50
48.75
49.00
49.25
49.50
49.75
33648
No
9,025
9,109
9,193
9,278
9,362
9,447
9,532
9,617
9,703
9,788
9,873
9,959
10,045
10,131
10,217
10,303
10,389
10,476
10,562
10,649
10,736
10,823
10,910
10,997
11,084
11,172
11,259
11,347
11,435
11,523
11,610
11,699
11,787
11,875
11,963
12,052
12,140
12,229
12,318
12,406
12,495
12,584
12,673
12,762
12,852
12,941
13,030
13,120
13,209
13,299
Tare:
Type:
50.00
50.25
50.50
50.75
51.00
51.25
51.50
51.75
52.00
52.25
52.50
52.75
53.00
53.25
53.50
53.75
54.00
54.50
55.00
55.50
56.00
56.50
57.00
57.50
58.00
58.50
59.00
59.50
60.00
60.50
61.00
61.50
62.00
62.50
63.00
63.50
64.00
119.00
100800
Outage Vapor
13,388
13,478
13,568
13,658
13,748
13,838
13,928
14,018
14,108
14,198
14,288
14,378
14,469
14,559
14,650
14,740
14,830
15,012
15,193
15,374
15,556
15,737
15,919
16,100
16,282
16,464
16,646
16,828
17,010
17,191
17,373
17,555
17,737
17,918
18,100
18,281
18,463
33,653
SECTION 1 — CALCULATION OF STATIC PETROLEUM QUANTITIES, PART 2 — CALCULATION PROCEDURES FOR TANK CARS
47
Table F-5 — Tank Car Capacity Table
Tank Car:
ACFX 79298
Capacity Table: ACF 1769
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
3.25
3.50
3.75
4.00
4.25
4.50
4.75
5.00
5.25
5.50
5.75
6.00
6.25
6.50
6.75
7.00
7.25
7.50
7.75
8.00
8.25
8.50
8.75
9.00
9.25
9.50
9.75
10.00
10.25
10.50
10.75
11.00
11.25
11.50
11.75
12.00
12.25
12.50
12.75
0
3
7
11
17
23
30
37
46
55
65
75
87
99
111
124
138
153
168
184
200
218
239
263
288
316
346
377
409
442
476
510
544
579
616
653
691
730
769
809
850
890
932
973
1,015
1,058
1,100
1,144
1,188
1,233
1,279
1,325
13.00
13.25
13.50
13.75
14.00
14.25
14.50
14.75
15.00
15.25
15.50
15.75
16.00
16.25
16.50
16.75
17.00
17.25
17.50
17.75
18.00
18.25
18.50
18.75
19.00
19.25
19.50
19.75
20.00
20.25
20.50
20.75
21.00
21.25
21.50
21.75
22.00
22.25
22.50
22.75
23.00
23.25
23.50
23.75
24.00
24.25
24.50
24.75
25.00
25.25
25.50
25.75
1,371
1,418
1,465
1,513
1,561
1,609
1,658
1,707
1,757
1,807
1,858
1,910
1,961
2,014
2,066
2,119
2,173
2,228
2,283
2,338
2,394
2,450
2,506
2,563
2,619
2,676
2,732
2,789
2,846
2,904
2,962
3,020
3,079
3,139
3,199
3,260
3,321
3,383
3,446
3,508
3,571
3,635
3,699
3,763
3,826
3,890
3,954
4,018
4,082
4,146
4,211
4,276
26.00
26.25
26.50
26.75
27.00
27.25
27.50
27.75
28.00
28.25
28.50
28.75
29.00
29.25
29.50
29.75
30.00
30.25
30.50
30.75
31.00
31.25
31.50
31.75
32.00
32.25
32.50
32.75
33.00
33.25
33.50
33.75
34.00
34.25
34.50
34.75
35.00
35.25
35.50
35.75
36.00
36.25
36.50
36.75
37.00
37.25
37.50
37.75
38.00
38.25
38.50
38.75
Nozzle Volume: 0
Nozzle Height: 13.375
4,341
4,406
4,472
4,538
4,605
4,672
4,739
4,807
4,874
4,941
5,009
5,076
5,144
5,212
5,280
5,348
5,417
5,485
5,554
5,623
5,693
5,763
5,833
5,904
5,975
6,046
6,118
6,191
6,264
6,337
6,410
6,484
6,557
6,631
6,704
6,778
6,852
6,926
7,001
7,075
7,150
7,224
7,299
7,374
7,449
7,524
7,599
7,674
7,750
7,825
7,901
7,976
39.00
39.25
39.50
39.75
40.00
40.25
40.50
40.75
41.00
41.25
41.50
41.75
42.00
42.25
42.50
42.75
43.00
43.25
43.50
43.75
44.00
44.25
44.50
44.75
45.00
45.25
45.50
45.75
46.00
46.25
46.50
46.75
47.00
47.25
47.50
47.75
48.00
48.25
48.50
48.75
49.00
49.25
49.50
49.75
50.00
50.25
50.50
50.75
51.00
51.25
51.50
51.75
8,052
8,128
8,204
8,280
8,356
8,433
8,509
8,585
8,662
8,738
8,815
8,892
8,969
9,046
9,123
9,200
9,277
9,355
9,432
9,510
9,588
9,666
9,745
9,823
9,902
9,980
10,059
10,138
10,217
10,296
10,375
10,454
10,534
10,613
10,693
10,772
10,852
10,931
11,011
11,091
11,170
11,250
11,330
11,409
11,489
11,569
11,649
11,728
11,808
11,888
11,967
12,047
52.00
52.25
52.50
52.75
53.00
53.25
53.50
53.75
54.00
54.25
54.50
54.75
55.00
55.25
55.50
55.75
56.00
56.25
56.50
56.75
57.00
57.25
57.50
57.75
58.00
58.25
58.50
58.75
59.00
59.25
59.50
59.75
60.00
60.25
60.50
60.75
61.00
61.25
61.50
61.75
62.00
62.25
62.50
62.75
63.00
63.25
63.50
63.75
64.00
64.25
64.50
64.75
Stencil Volume:
Nozzle Height Included?
12,127
12,206
12,286
12,366
12,446
12,526
12,606
12,686
12,766
12,846
12,927
13,007
13,087
13,167
13,248
13,328
13,408
13,489
13,569
13,650
13,730
13,810
13,891
13,971
14,051
14,132
14,212
14,292
14,372
14,452
14,532
14,612
14,692
14,772
14,852
14,932
15,011
15,091
15,171
15,251
15,331
15,411
15,491
15,571
15,651
15,731
15,811
15,891
15,971
16,051
16,131
16,210
65.00
65.25
65.50
65.75
66.00
66.25
66.50
66.75
67.00
67.25
67.50
67.75
68.00
68.25
68.50
68.75
69.00
69.25
69.50
69.75
70.00
70.25
70.50
70.75
71.00
71.25
71.50
71.75
72.00
72.25
72.50
72.75
73.00
73.25
73.50
73.75
74.00
74.25
74.50
74.75
75.00
75.25
75.50
75.75
76.00
76.25
76.50
76.75
77.00
77.25
77.50
77.75
16,290
16,370
16,450
16,529
16,609
16,688
16,768
16,847
16,926
17,005
17,084
17,163
17,242
17,320
17,398
17,477
17,555
17,633
17,710
17,788
17,865
17,943
18,020
18,097
18,174
18,250
18,327
18,404
18,480
18,557
18,633
18,709
18,785
18,861
18,937
19,013
19,089
19,164
19,240
19,315
19,391
19,466
19,541
19,616
19,691
19,766
19,841
19,916
19,990
20,065
20,139
20,214
26859
No
78.00
78.25
78.50
78.75
79.00
79.25
79.50
79.75
80.00
80.25
80.50
80.75
81.00
81.25
81.50
81.75
82.00
82.25
82.50
82.75
83.00
83.25
83.50
83.75
84.00
84.25
84.50
84.75
85.00
85.25
85.50
85.75
86.00
86.25
86.50
86.75
87.00
87.25
87.50
87.75
88.00
88.25
88.50
88.75
89.00
89.25
89.50
89.75
90.00
90.25
90.50
90.75
20,288
20,362
20,436
20,510
20,584
20,658
20,732
20,805
20,878
20,951
21,024
21,096
21,168
21,239
21,311
21,382
21,453
21,523
21,594
21,664
21,734
21,803
21,873
21,942
22,011
22,080
22,149
22,218
22,287
22,355
22,423
22,491
22,558
22,624
22,691
22,757
22,822
22,888
22,953
23,018
23,082
23,147
23,211
23,275
23,340
23,403
23,465
23,526
23,587
23,647
23,707
23,767
Tare: 65900
Type: Innage Liquid
91.00
91.25
91.50
91.75
92.00
92.25
92.50
92.75
93.00
93.25
93.50
93.75
94.00
94.25
94.50
94.75
95.00
95.25
95.50
95.75
96.00
96.25
96.50
96.75
97.00
97.25
97.50
97.75
98.00
98.25
98.50
98.75
99.00
99.25
99.50
99.75
100.00
100.25
100.50
100.75
101.00
101.25
101.50
101.75
102.00
102.25
102.50
102.75
103.00
103.25
103.50
103.75
23,827
23,888
23,949
24,010
24,070
24,131
24,191
24,251
24,310
24,368
24,425
24,482
24,539
24,595
24,650
24,705
24,759
24,813
24,866
24,919
24,971
25,023
25,075
25,126
25,176
25,226
25,276
25,325
25,374
25,423
25,471
25,520
25,568
25,616
25,664
25,711
25,757
25,803
25,847
25,891
25,933
25,975
26,018
26,060
26,102
26,143
26,183
26,223
26,262
26,299
26,335
26,370
104.00
104.25
104.50
104.75
105.00
105.25
105.50
105.75
106.00
106.25
106.50
106.75
107.00
107.25
107.50
107.75
108.00
108.25
108.50
108.75
26,403
26,434
26,463
26,493
26,524
26,555
26,586
26,616
26,645
26,674
26,701
26,727
26,750
26,772
26,791
26,807
26,820
26,830
26,836
26,838
48
CHAPTER 12 — CALCULATION OF PETROLEUM QUANTITIES
Bibliography
1. API Manual of Petroleum Measurement Standards (MPMS) Chapter 7, Temperature Determination
2. API Manual of Petroleum Measurement Standards (MPMS) Chapter 11.1, Temperature and Pressure Volume
Correction Factors for Generalized Crude Oils, Refined Products, and Lubricating Oils
3. API Manual of Petroleum Measurement Standards (MPMS) Chapter 11.5, Density / Weight / Volume
Intraconversion, Part 1 — Conversions of API Gravity at 60 °F
4. API Manual of Petroleum Measurement Standards (MPMS) Chapter 11.5, Density / Weight / Volume
Intraconversion, Part 2 — Conversions for Relative Density (60 / 60 °F)
5. API Manual of Petroleum Measurement Standards (MPMS) Chapter 12.1.1, Calculation of Petroleum Quantities
– Upright Cylindrical Tanks and Marine Vessels
6. Std 2554 Measurement and Calibration of Tank Cars
7. GPA, 8195-952, Tentative Standard for Converting Net Vapor Space Volumes to Equivalent Liquid Volumes
8. U.S. DOT Title 49 Code of Federal Regulations (CFR) Parts 106 to 1803
9. U.S. DOT Title 49 Code of Federal Regulations (CFR) Chapter II, Part 215.201
10. AAR Manual of Standards and Recommended Practices, Section C, Part III, Specifications for Tank Cars, M100214