API MPMS Chapter 11.1 (R2012)

Provides the algorithm and implementation procedure for the correction of temperature and pressure effects on density and volume of liquid hydrocarbons which fall within the categories of crude oil, refined products, or lubricating oils. A special application category is also provided which provides volume correction based on the input of an experimentally derived coefficient of thermal expansion. Natural gas liquids and liquefied petroleum gases are excluded from consideration in this Standard (see Ch. 11.2.2 and Ch. 11.2.4). Including the pressure correction in Ch. 11.1 represents an important change from the “temperature only” 1980 Petroleum Measurement Tables. However, if the pressure is one atmosphere (the standard pressure) then there is no pressure correction and this Standard will give values for a correction for the effect of temperature on liquid (CTL) consistent with the 1980 Tables. The (2004 edition of this) Standard (revised Standard) was effective on the date of publication and supersedes the previous (1980) edition of the Standard(s). However, due to the nature of the changes in this revised Standard, it is recognized that guidance concerning an implementation period may be needed in order to avoid disruptions within the industry and ensure proper application. As a result, it is recommended that this revised Standard be utilized on all new applications no later than TWO YEARS after the publication date. An application for this purpose is defined as the point where the calculation is applied. Once the revised Standard is implemented in a particular application, the previous Standard will no longer be used in that application. If an existing application complies with the previous Standard(s) then it shall be considered in compliance with this revised Standard. However, the use of API standards remains voluntary and the decision on when to utilize a standard is an issue that is subject to the negotiations between the parties involved in the transaction.