1.1 This guide provides information related to the algorithm and implementation procedure but does not contain the full set of algorithms. The algorithms, instructions, procedures, and examples are located in the associated supplementary adjuncts. The Adjunct for Volume Correction Factors (VCF) for temperature and pressure volume correction factors for generalized crude oils, refined products, and lubricating oils provides the algorithm and implementation procedure for the correction of temperature and pressure effects on density and volume of liquid hydrocarbons. Natural gas liquids (NGLs) and liquefied petroleum gases (LPGs) are excluded from consideration in this standard but may be found in API MPMS Chapter 11.2.4/GPA 8217 Temperature Correction for NGL and LPG. As this Adjunct for VCF will be applied to a variety of applications, the output parameters of CTL, F_p, CPL, and CTPL may be used as specified in other standards.

1.2 Including the pressure correction in the Adjunct for VCF represents an important change from the “temperature only” correction factors given in the 1980 Petroleum Measurement Tables. However, if the pressure is one atmosphere (the standard pressure), then there is no pressure correction and the standard/adjunct(s) will give CTL values consistent with the 1980 Petroleum Measurement Tables.

1.3 The Adjunct for VCF covers general procedures for the conversion of input data to generate CTL, F_p, CPL, and CTPL values at the user-specified base temperature and pressure (T_b, P_b). Two sets of procedures are included for computing volume correction factor: one set for data expressed in customary units (temperature in °F, pressure in psig); the other for the metric system of units (temperature in °C, pressure in kPa or bar).

1.4 The procedures in the Adjunct for VCF recognize three distinct commodity groups: crude oil, refined products, and lubricating oils. A procedure is also provided for determining volume correction for special applications where the generalized commodity groups’ parameters may not adequately represent the thermal expansion properties of the liquid and a precise thermal expansion coefficient has been determined by experiment. Procedures for determining Volume Correction Factors (VCF) for Denatured Ethanol can be found in API MPMS Chapter 11.3.3, Miscellaneous Hydrocarbon Properties—Denatured Ethanol Density and Volume Correction Factors, 3^rd edition. Procedures for determining Volume Correction Factors (VCF) for Gasoline and Denatured Ethanol Blends can be found in API MPMS Chapter 11.3.4, Miscellaneous Hydrocarbon Properties—Denatured Ethanol and Gasoline Component Blend Densities and Volume Correction Factors, 1^st edition.

1.5 The values stated in either SI units or inch‐pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.

1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.