SECTION 2, PART 5-CALCULATION OF BASE PROVER VOLUME BY MASTER METER METHOD 3 5.1.6 calibration run set: A series of events that involve making multiple consecutive runs of a master pro
Part 2-Calculation of Metered Quantities
3.2.1 The application of this standard to the calculation of metered quantities is presented, for base volumetric cal- culations in conformance with North American industry practices
The article outlines the recording of field data, including rules for rounding, discrimination levels, and calculation sequences It provides a detailed explanation of the calculation steps, accompanied by flow charts and example calculations These examples serve as a valuable resource for verifying procedures in any computer calculation routines developed according to the specified requirements.
Part3-ProvingReports
This standard is applied to the calculation of proving reports, focusing on base volumetric calculations that align with North American industry practices Proving reports are essential for determining meter correction factors and performance indicators.
2 CHAPTER 12-CALCULATION OF PETROLEUM QUANTITIES determination of the appropriate terms is based on both the hardware and the preferences of the users
Section 3.3.2 outlines the procedures for recording field data, including rules for rounding, calculation sequences, and discrimination levels It also provides a series of example calculations intended to assist in the checkout processes for any computer routines developed in accordance with these specified requirements.
Part &Calculation of Base Prover Volumes by Waterdraw Method
The waterdraw method involves displacing water from a prover into certified volumetric field standard test measures, or from these measures into an open tank prover in the case of open tank provers It is essential that the certification of the field standard measures is traceable to a recognized national weights and measures organization.
Section 3.4.2 outlines the procedures for recording field data, including rules for rounding, calculation sequences, and discrimination levels It also provides a series of example calculations to assist in the checkout processes for any routines developed according to the specified requirements.
Part 5-Calculation of Base Prover Volumes by Master Meter Method
VOLUMES BY MASTER METER METHOD
The master meter method employs a transfer meter, also known as a transfer standard, which is validated under real operating conditions using a prover that has been calibrated through the waterdraw method, referred to as the master meter This master meter is essential for determining the calibrated volume of a field displacement prover.
Section 3.5.2 outlines the procedures for recording field data, including rules for rounding, calculation sequences, and discrimination levels It also provides a series of example calculations to assist in the checkout processes for any routines developed based on the specified requirements.
Several documents served as references for the revisions of this standard In particular, previous editions of APZ MPMS
Chapter 12.2 (ANSUAPI 12.2) provided a wealth of informa- tion Other publications served as a resource of information:
Manual of Petroleum Measurement Standards (MPMS)
Chapter 13-“Statistical Aspects of Measuring and
Dl550 ASTM Butadiene Measurement Tables
Petroleum Measurement Tables, Current Edition
Petroleum Measurement Tables, Historical Edi- tion, 1952
Calculation of Volume And Weight of Industrial Aromatic Hydrogens
N I S T ~ Handbook 105-3 Handbook 105-7 Small Volume Provers
SpeciJications and Tolerances for Ref- erence Standards and Field Standards
Terms and symbols described below are acceptable and in common use for the calibration of flow meters.
DefinitionofTemis
5.1.1 barrel (Bbl): A unit volume equal to 9,702.0 cubic inches, or 42.0 U S gallons
The base prover volume (BPV) refers to the volume of the prover under standard conditions, as indicated on the calibration certificate It is determined by calculating the arithmetic average of a sufficient number of consecutive calibrated prover volume (CPV) measurements.
5.1.3 calibrated prover volume (CPV): The volume at base conditions between the detectors in a unidirectional prover, or the volume of a prover tank between specified
The calibrated volume (CPV) of a bidirectional prover is defined as the total volume measured between detectors during a calibration round-trip, encompassing both the "empty" and "full" levels established by a single calibration run.
5.1.4 cubic meter (m3): A unit of volume equal to 1,000,000.0 milliliters (mi), or 1,000.0 liters One cubic meter equals 6.28981 barrels
A calibration certificate is a crucial document that specifies the base prover volume (BPV) along with the physical data utilized in its calculation, such as E, Gc, Ga, and GI This certificate is issued by the American Society for Testing and Materials, located at 100 Barr Harbor Drive, West Conshohocken, Pennsylvania 19428.
2U.S Department of Commerce, National Institute of Standards and Technology (formerly the National Bureau of Standards), Washing- ton, D.C 20234
SECTION 2, PART 5-CALCULATION OF BASE PROVER VOLUME BY MASTER METER METHOD 3
A calibration run set consists of a sequence of events where multiple consecutive runs of a previously water-drawn master prover are conducted to establish the start master meter factor (MMFstart) Following this, additional consecutive runs with the master meter are performed to calibrate the field prover and gather run data Finally, more consecutive runs with the master prover are executed to verify the master meter and determine the stop master meter factor.
(MMFstop) The average of the MMFstart, and the MMFstop is then used with the collected run data to determine a cali- brated prover volume (CPV) for that Calibration Run Set
The term "5.1.7 certified" indicates that a pressure or temperature device has undergone calibration across its operational range, ensuring it meets standards that are traceable to a national benchmark.
5.1.8 field prover: Refers to the volumetric standard (dis- placement prover) that is to be proved by using the master meter method
5.1.9 gross standard volume (GSV): The meteredvol-
Ume corrected to base conditions and also corrected for the performance of the meter (ME MMF)
5.1.10 indicated volume (IV): The change in the meter register head volume that occurs during a proving run (MRo-
MRc) The word registration, though not preferred, often has the same meaning Alternately, indicated volume (IV) may also be determined by dividing the meter pulse output, (N> or
(Ni), during a proving pass, by the nominal K-factor (NKF)
5.1.11 indicated standard volume (ISV): The indi- cated volume (IV) corrected to base conditions
The K-factor (KF) is defined as the number of pulses generated by a meter per unit volume During each proving, a new K-factor can be established to adjust the indicated volume If a new K-factor is not applied, the nominal K-factor can be used to create a new meter factor, which will correct the indicated volume to reflect the gross volume accurately.
5.1.13 liter (I): A unit of volume equal to 1,000.0 millili- ters (mi) or 0.001 cubic meters
A master meter is a certified transfer device used to calibrate other meter provers or verify flow meters It is typically a positive displacement or turbine meter that does not include mechanical or built-in temperature or gravity corrections, as detailed in Chapter 4.
The master meter factor (MMF) is a dimensionless term calculated by dividing the gross standard volume of liquid measured by the master prover during the meter's proving process by the indicated standard volume.
A 6 master prover is a volumetric standard, such as a displacement prover or open tank prover, that has been calibrated using the waterdraw method with test measures linked to a national standards organization This calibrated prover is then utilized to calibrate a master meter.
The nominal K-factor (NKF) is essential for determining the meter factor, as it is a manufacturer-generated value used to convert meter pulses (N> or (Ni) into indicated volume (IV) during meter proving Many installations maintain this K-factor throughout their operational life to ensure a reliable audit trail for meter proving.
5.1 I 8 pass: A single movement of the displacer between detectors which define the calibrated section of a prover
5.1.19 round-trip: The combined forward (out) and reverse (back) passes of the displacer in a bidirectional prover
A 5.1.20 run for meter proving involves either a single pass of a unidirectional prover, a round-trip of a bidirectional prover, or the emptying or filling of a volumetric prover tank The outcome of this process is considered acceptable for determining a single test value of the master meter factor (MMF) when applying the average meter factor calculation method.
A single test value of the calibrated prover volume (CPV) can be obtained through one pass of a unidirectional prover, one roundtrip of a bidirectional prover, or by filling or emptying a volumetric prover tank, provided the results are deemed acceptable.
5.1.22 U.S gallon (gal): A unit volume equal to 231.0 cubic inches.
Definition of Symbols
This publication utilizes a mix of upper and lower case notation for symbols and formulas, avoiding subscripted notation due to its complexity in computer and word processing applications While subscripted notation is not included, it can be used upon request Upper case notation is generally favored for computer programming and similar documents.
Symbols are essential for enhancing the clarity and specificity of mathematical treatments For instance, CTL stands for Correction for the effect of Temperature on the Liquid, GSV denotes Gross Standard Volume, MMF refers to Master Meter Factor, and CPS indicates Correction for Pressure on the Steel Additionally, symbols may have extra letters appended to clarify their meaning and application, such as "mm" for master meter, "p" for prover, "mp" for master prover, and "b" for base conditions (DEA%).
Chapter 12 focuses on the calculation of petroleum quantities, emphasizing the observed conditions (RHOobs) and the average (mean) of the readings denoted as [Tp(avg)] Any additional letters used in the context are designed to be easily interpretable.
International System of units (pascal, cubic meter, kilogram, metric system)
US Customary units (inch, pound, cubic inch, traditional system)
WT Wall thickness of prover
Inside diameter of the prover
Outside diameter of the prover
Density of liquid in degree API gravity units
Base density in degree API gravity units
Observed density at base pressure in degree API gravity units
Density of liquid in kilogram per cubic meter (kg/m3) units
Base density of liquid in kilogram per cubic meter (kg/m3) units
Observed density of liquid at base pressure in kilogram per cubic meter (kg/m3) units
Relative density of the liquid
Base relative density of the liquid
Observed relative density of the liquid at base pressure
Density of liquid (SI or USC) in mass per unit volume
Base density of liquid in mass per unit volume
Observed density of liquid at base pressure in mass per unit volume
Density of liquid in the prover (for master meter calculations) in mass per unit volume
Density of the liquid at operating temperature and pressure in mass per unit volume
VZSb Base liquid viscosity in CP units (if needed)
Base temperature, in "F or "C units
Temperature of detector mounting shaft on
The temperature readings for the master meter, master prover, and field prover are recorded in either Fahrenheit or Celsius units Additionally, the observed temperature, which is used to determine the relative density of the fluid (RHOb), is also measured in Fahrenheit or Celsius.
Pe Peb Pem Pemm Pemp
Kilopascals (SI) in absolute pressure units Kilopascals (SI) in gauge pressure units Pounds per square inch (üSC) pressure units Pounds per square inch (USC) in absolute pres- sure units
Pounds per square inch (USC) in gauge pres- sure units
Operating pressure in gauge pressure units Base pressure, in psi or P a pressure units Base pressure, in absolute pressure units Base pressure, in gauge pressure units
Pressure of liquid in the master meter, in gauge pressure units
Pressure of liquid in field prover, in gauge pres- sure units
Pressure of liquid in the master prover, in gauge pressure units
Internal operating pressure of prover, in gauge pressure units
The equilibrium vapor pressure of a liquid is measured in absolute pressure units under normal operating conditions Additionally, it is also defined at a base temperature, again expressed in absolute pressure units Furthermore, the equilibrium vapor pressure can be represented in meters, maintaining the same absolute pressure unit standard.
Equilibrium vapor pressure of liquid in master meter, in absolute pressme units
Equilibrium vapor pressure of liquid in master prover, in absolute pressure units
CCFmm Combined correction factor for master meter at proving conditions
CCFp Combined correction factor for field prover at proving conditions
SECTION 2, PART 5-CALCULATION OF BASE PROVER VOLUME BY MASTER METER METHOD 5
Combined correction factor for master prover at proving conditions
Basic correction for the compressibility of a liquid
Correction for the Compressibility of liquid in the field prover at operating conditions
Correction for the Compressibility of liquid in the master prover at operating conditions
Correction for the Compressibility of liquid in the master meter at operating conditions
Basic correction for the effect of pressure on steel
Correction for the effect of pressure on steel field prover
Correction for the effect of pressure on steel master prover
Basic correction for effect of temperature on a liquid
Correction for the effect of temperature on a liquid in field prover
Correction for the effect of temperature on a liquid in master prover
Correction for the effect of temperature on a liquid in the master meter
Basic correction for the effect of temperature on steel
Correction for the effect of temperature on steel in field prover
Correction for the effect of temperature on steel master prover
Modulus of elasticity of the steel prover
Compressibility factor of liquid in meter (for
Compressibility factor of liquid in field prover
Compressibility factor of liquid in master prover
Compressibility factor of liquid in master meter
Linear coefficient of thermal expansion on dis- placer shaft or detector mounting
Area coefficient of thermal expansion of prover
Cubical coefficient of thermal expansion of prover
Cubical coefficient of thermal expansion of master prover
MMFstart Master meter factor determined at the start of a prover calibration run for one calibration run set
MMFstop Master meter factor determined at the stop of a prover calibration run for one calibration run set
MMFmg The average of MMFstart and MMFstop ZMMF Intermediate master meter factor as derived in the average meter factor method
KF K-factor, pulses per Unit volume
NKF Nominal K-factor, pulses per Unit volume
GSV GSVp GSVmp GSVmm zv
Calibrated prover volume for a single prover calibration run (round trip for bidirectional prover)
Base prover volume of a displacement prover Adjusted base prover volume for master tank prover
Gross standard volume of field prover for prov- ing operations
Gross standard volume of master prover for proving operations
Gross standard volume when using a master meter for proving operations
Indicated volume of master meter for proving operations
Indicated standard volume of the master meter Opening master meter reading
Number of whole meter pulses for a single proving pass or round-trip
Number of interpolated meter pulses for a sin- gle proving pass or round-trip
Average number of pulses or interpolated meter pulses for the proving runs that satis6 the repeatability requirements
Base volume of each pass of the field prover Base volume of ?out? pass of a bidirectional field prover
Base volume of ?back? pass of a bidirectional field prover
Upper scale reading of atmospheric tank prover Lower scale reading of atmospheric tank prover
6 CHAPTER 12-CALCULATION OF PETROLEUM QUANTITIES
6.1 For fiscal and custody transfer applications, prov- ers are transfer standards which are used to calibrate flowmeters
6.2 The purpose of calibrating a prover is to determine its volume at reference conditions (base prover volume)
The base prover volume (BPV) of a prover can be determined using either the water draw method or the master meter method The master meter method involves a volumetric calibration process where the base volume of a displacement prover is established by connecting it in series with a master meter and a master prover, which has been previously calibrated using the water draw method During the calibration, liquid flows through all three devices, and the volume measured by the master meter, adjusted to reference conditions, is considered the reference volume This collected volume is then corrected for any pressure or temperature differences between the test volume and the master meter, resulting in the designated base volume of the test element (field prover) For visual reference, see Figures 1, 2, and 3 for typical configurations.
6.4 The master meter method of determining the base vol- ume of a prover is an indirect method of calibrating a prover
The function of the master meter is to serve as an intermediate link between the prover and the volumetric standard
Standardizing terms and arithmetic procedures for calculating the BPV is essential to prevent disagreements among the parties involved in the facility Part 5 focuses on the "Calculation of Prover Base Volume," ensuring clarity and consistency in the process.
The "Master Meter Method" ensures an unbiased outcome from identical measurement data, independent of the individual or system performing the calculations This approach culminates in the generation of the prover's calibration certificate.
6.6 A calibration certificate serves as document stating the base volume of the prover (BPV) and also reports the physical data used to calculate that base prover volume
The article outlines the procedures for recording field data, including rules for rounding, the sequence of calculations, and discrimination levels It also provides example calculations to assist in the checkout processes for routines developed according to these specified requirements.
6.8 The operational procedures employed to calibrate a prover are specified in A P Z MPMS Chapter 4-"Proving
Applicable Liquids
This standard is applicable to liquids that are deemed clean, single-phase, homogeneous, and Newtonian under metering conditions Typically, most liquids, particularly those in the petroleum and petrochemical industries, are classified as Newtonian fluids.
The application of this standard is restricted to liquids that use tables or implementation procedures to adjust metered volumes at flowing temperatures and pressures to corresponding volumes at base conditions To achieve this, the liquid's density must be determined using the appropriate technical standard, a suitable density correlation, or, if necessary, the correct equations of state In cases where multiple parties are involved in the measurement, the method for determining the liquid's density must be agreed upon by all parties involved.
Base Conditions
7.2.1 Historically, the measurement of some liquids for custody transfer and process control, have been stated in vol- ume units at base (reference or standard) conditions
The fundamental conditions for measuring liquids, including crude petroleum and its liquid derivatives, are established for those with a vapor pressure that is equal to or lower than atmospheric pressure at the base temperature.
United States Customary (üSC) Units:
7.2.3 For fluids, such as liquid hydrocarbons, having a vapor pressure greater than atmospheric pressure at base tem- perature, the base pressure shall be the equilibrium vapor pressure at base temperature
In liquid applications, base conditions can vary significantly between countries due to differing governmental regulations It is essential to identify and specify these base conditions to ensure standardized volumetric flow measurements.
Systems" ment by all parties involved in the measurement
SECTION 2, PART 5-CALCULATION OF BASE PROVER VOLUME BY MASTER METER METHOD 7
8 CHAPTER 12-CALCULATION OF PETROLEUM QUANTITIES
The minimum precision of the computing hardware must be equal to or greater than a ten digit calculator to obtain the same answer in all calculations
The general rounding rules and discrimination levels are described in the following subsections
When rounding a number to a specific number of decimal places, it should be done in a single step rather than through multiple successive rounds The rounding rules are as follows: if the digit to the right of the last retained decimal is 5 or greater, the last retained digit is increased by 1; if it is less than 5, the last retained digit remains unchanged.
8.2.1 For field measurements of temperature and pressure the levels specified in the various tables are maximum dis- crimination levels
8.2.2 For example, if the parties agree to use a thermometer graduated in whole "F or l/2"C increments, then the device is normally read to levels of 0.5"F or 0.25"C resolution
If the parties decide to utilize a "smart" temperature transmitter capable of measuring temperatures to 0.01°F or 0.005°C, the recorded readings must be rounded to the nearest 0.1°F or 0.05°C for calculation purposes.
The base prover volume (BPV) calculation using the master meter method begins with proving the master meter against a master prover using the selected liquid for field prover calibration This master meter serves as the reference standard for calibrating the field prover.
There are two general classes of liquid provers: displace- ment provers and open tank provers
Subclasses of displacement provers are unidirectional and bidirectional flow designs, as well as small volume provers
SECTION 2, PART 5-CALCULATION OF BASE PROVER VOLUME BY MASTER METER METHOD 9
Figure 3-Field Prover Calibration with external detectors which may also be of the unidirec- tional or bidirectional construction
Subclasses of open tank provers are top flling or bottom filling designs
For unidirectional displacement field provers, a minimum of three consecutive calibration run sets is necessary to ensure accurate calibration Each calibration run set must achieve an average calibrated prover volume that meets specified criteria.
The average CPV (CPVavg) at reference conditions for three or more consecutive passes should show a variation of 0.020% or less Additionally, the flow rate between consecutive calibration run sets must be altered by at least 25% or more.
Each calibration run set must follow a specific sequence and meet defined criteria First, conduct five or more consecutive master meter proving runs against the master prover to establish the MMFstart, ensuring that these values agree within a range of 0.020% or less Next, perform three or more consecutive field prover calibration runs with the master meter to determine the calibrated prover volume (CPVn), with a maximum of six runs allowed.
At reference conditions, the volumes must show a variation of 0.020% or less To determine the MMFstop, conduct five or more consecutive master meter proving runs out of a maximum of ten, ensuring that these MMFstops agree within the same 0.020% range During each calibration run set, maintain the flow rate within a 2.5% range Additionally, the delta percentage between the average of the five or more consecutive MMFstarts and the average of the five or more consecutive MMFstops in each calibration run set must also agree within 0.020%.
9.2.1 For bidirectional displacement field provers, three or more consecutive calibration run sets of the field prover are required for a calibration which shall meet the follow- ing criteria:
10 CHAPTER 12-CALCULATION OF PETROLEUM QUANTITIES
Excluding range criteria for the "out" and "back" run set average volumes diminishes the statistical rigor of this method The average "round-trip" calibrated prover volume (CPVavg) at reference conditions should display a range across three or more consecutive calibration run sets.
0.020% or less b The flow rate between consecutive calibration run sets shall be changed by at least 25% or more
Each calibration run set must follow a specific sequence and meet defined criteria First, conduct five or more consecutive master meter proving runs against the master prover to establish MMFstart, ensuring that these MMFstarts agree within a range of 0.020% or less Additionally, perform three or more consecutive field prover round-trip calibration runs with the master meter to calculate the average "out" pass volume, with a maximum of six runs allowed.
Vb(out), average “back” pass volume Vb(back) and average
To ensure accurate measurements, the average round-trip volume (CPVavg) must be validated by conducting three or more consecutive calibrated prover volumes (CPVn) at reference conditions, which should show a variation of 0.020% or less Additionally, it is essential to perform five or more consecutive master meter proving runs against the master prover to determine MMFstop, with these MMFstops also agreeing within a range of 0.020% During each calibration run set, the flow rate should be maintained within a 2.5% range Furthermore, the percentage difference between the average of the five or more consecutive MMFstarts and the average of the five or more consecutive MMFstops in each calibration run set must also align within 0.020%.
9.3.1 The use of open tank provers, in this standard, are restricted to master provers only and shall not be calibrated by the master meter method
9.3.2 For open tank master provers, the calibration sequence is the same as for the unidirectional displacement provers, see 9.1
As a measure of repeatability, the following equation shall be utilized to calculate and veri@ the range results:
9.5 CALCULATION METHODS FOR PROVING THE
Two different meter factor calculation methods are in com- mon use and described in this text The two methods have been designated, the Average Meter Factor Method, and the
The Average Meter Factor method determines an Intermediate Master Meter Factor (ZMMF) for each selected run by utilizing individual values of temperature and pressure (Tp, Tmm, Pp, Pmm) along with the number of runs (N) and individual runs (Ni) The average of these calculated ZMMFs is then used to establish the Master Meter Factors (MMFstart) and (MMFstop), which are essential for computing the Average Master Meter Factor (MMFavg) for a calibration run set The percentage range (R%) is calculated using the formula: \[R\% = \frac{High(ZMMF) - Low(ZMMF)}{Low(ZMMF)} \times 100\]
9.5.1.2 The range of the intermediate master meter factors, for a calibration run set, is used to determine that the required repeatability requirement (< 0.020 percent) has been satisfied
The Average Data Method determines the Master Meter Factor (MMFstart) and (MMFstop) by utilizing average values of Tp, Tmm, Pp, Pmm, and N from all selected runs that meet the repeatability criteria outlined in section 9.3.
9.5.2.2 The range of the pulses (N), or interpolated (Ni), for the selected runs, is used to determine that the required repeatability requirement (< 0.020 percent) has been satisfied
If all parties consent, meter proving can be conducted between each field prover calibration run within a calibration set This process involves an MMFstop and MMFstart between each calibration run Each master meter proving consists of five consecutive runs, maintaining a precision of 0.020% within a maximum of five runs A calibration set includes three consecutive field prover runs, also adhering to a 0.020% accuracy within a maximum of six runs The MMFstop at the conclusion of each calibration run can serve as the MMFstart for the subsequent run.