BS ISO 91:2017

This standard BS ISO 91:2017 Petroleum and related products. Temperature and pressure volume correction factors (petroleum measurement tables) and standard reference conditions is classified in these ICS categories:

• 75.180.30 Volumetric equipment and measurements

This document refers to temperature volume correction factors, which allow users to convert volumes, measured at ambient conditions, to those at reference conditions for transactional purposes. This document also refers to compressibility factors required to correct hydrocarbon volumes measured under pressure to the corresponding volumes at the equilibrium pressure for the measured temperature.

Table 1 shows the defining limits and their associated units of correction factors referenced in this document for crude oil, refined products and lubricating oils. These values are shown in bold italics . Also shown in the table are the limits converted to their equivalent units (and, in the case of the densities, other base temperatures). Table 2 shows defining limits of correction factors for light hydrocarbons (natural gas liquids and liquefied petroleum gases).

Table 1

Defining limits of correction factors for crude oil, refined products and lubricating oils

	Crude oil	Refined products	Lubricating oils
Density, kg/m3 @ 60 °F	610,6 to 1 163,5		800,9 to 1 163,5
Relative density @ 60 °F	0,611 2 to 1,164 64		0,801 68 to 1,164 6
API gravity @ 60 °F	100 to –10		45 to –10
Density, kg/m3 @ 15 °C	611,16 to 1 163,79	611,16 to 1 163,86	801,25 to 1 163,85
Density, kg/m3 @ 20 °C	606,12 to 1 161,15	606,12 to 1 160,62	798,11 to 1 160,71
Temperature, °C	–50,00 to 150
Temperature, °F	–58,0 to 302
Pressure, psig	0 to 1 500
Pressure, kPa (gauge)	0 to 1,034 × 104
Pressure, bar (gauge)	0 to 103,4
60 °F thermal expansion factor (α60), per °F	230,3 × 10 − 6 to 930,0 × 10−6
α60, Per °C	414,0 × 10−6 to 1 674,0 × 10−6

Table 2

Defining limits of correction factors for light hydrocarbons (natural gas liquids and liquefied petroleum gases)

Density, kg/m3 @ 60 °F Density, kg/m3 @ 15 °C Density, kg/m3 @ 20 °C	350,0 to 688,0 351,7 to 687,8 331,7 to 683,6
Temperature °C Temperature °F	−46,0 to 93,0 −50,8 to 199,4
Pressure	Saturation conditions (bubble point or saturation vapour pressure) (see Note 2 to 4.1)

This document also specifies standard reference conditions of pressure and temperature for measurements carried out on crude petroleum and its products, including liquefied petroleum gases (see Annex B).

This document excludes specifying standard reference conditions for natural gas which are given in ISO 13443^[15].