GB/T 9109.5-2025 Dynamic Measurement of Petroleum and Liquid Petroleum Products Part 5: Oil Quantity Calculation

scope
This document specifies the general requirements and technical requirements for dynamic measurement and oil quantity calculation of petroleum and liquid petroleum products, including numerical rounding, basic data preparation, oil quantity calculation methods, and handover of measurement vouchers.
This document is applicable to the dynamic measurement of oil quantity calculation for commodity petroleum and liquid petroleum products (hereinafter referred to as oil products), and is not applicable to the oil quantity calculation of liquefied petroleum gas and stable light hydrocarbons. The oil quantity calculation for non commodity petroleum can refer to it.

Terms and definitions
The terms and definitions defined in JJF 1001 and JJF 1004, as well as the following, apply to this document.
Indicating volume or mass
Vt, ormt
During the measurement period, the flowmeter displays the cumulative increase in volume or mass of the oil directly recorded by the unit under working conditions.
Note 1: The indicated volume or mass of the oil product is the original output of the flowmeter, without mathematical compensation correction for temperature, pressure, air buoyancy, etc.
Note 2: The indicated volume or mass of the oil product includes water and sediment.
Temperature of measurement
t
During the measurement period, the arithmetic mean or weighted average of the temperature results of the oil at the flowmeter is measured at a fixed frequency.
Pressure of measurement
p
During the measurement period, the arithmetic mean or weighted average of the oil pressure results measured at the flowmeter at a fixed frequency.
Water and sediment
SW
During the measurement period, the content (volume fraction or mass fraction) of water and sediment in oil products is determined by sampling laboratory analysis or online analytical instruments.
Note: This term is often abbreviated as' water containing 'in industry usage.
Compressibility factor
F
Characterize the characteristic parameters of the volume change of oil products with pressure under isothermal conditions.
Correction factor for liquid pressure
C_pl
A parameter used to correct the volume deviation of oil caused by the difference between measuring pressure and equilibrium pressure.
Note: When the saturated vapor pressure of the oil at the measuring temperature does not exceed the local atmospheric pressure, the equilibrium pressure is taken as the standard reference pressure; When the saturated vapor pressure of the oil product at the measuring temperature exceeds the local atmospheric pressure, the equilibrium pressure is taken as the saturated vapor pressure value at that temperature.
Correction factor for liquid temperature
C_tl
A parameter used to correct the volume deviation of oil caused by the difference between the measured temperature and the standard temperature.
Correction factor for water content
C_sw
A dimensionless parameter that characterizes the influence of water content on the measurement results of oil quantity.
Note: According to different ways of expressing water content, it can be divided into volumetric water content correction coefficient and mass water content correction coefficient.
Buoyancy correction factor
F_a
A dimensionless parameter that characterizes the influence of air buoyancy on the measurement results of oil quality.
Gross volume or mass
V_g,m_gm
Under working conditions, indicate the volume or mass of the oil product after being corrected by the flow meter coefficient or instrument coefficient.
Gross standard volume
V_gs
Convert the gross volume to the volume of oil under standard reference conditions.
Net standard volume
V_ns
Convert the gross volume to the standard reference conditions and deduct the volume of the oil after deducting the water content.
Gross observed mass
m_gw
The quality of oil products with air buoyancy correction for gross weight.
Net mass
m_nm
Subtract the quality of oil containing water from the gross quality.
Net observed mass
m_nw
The quality of the oil product after deducting moisture content and correcting for air buoyancy.
Basic error method
When the flowmeter meets the allowable error requirements during the calibration period, the uncorrected flowmeter indicating volume or mass is directly used as the gross volume or mass for oil quantity calculation.
Meter factor method
The oil quantity calculation method that uses the flow meter coefficient or instrument coefficient determined by the calibration of the flow meter to correct the indicated volume or mass.

symbol
The following symbols are applicable to this document (see Table 1).






Preparation of Basic Data
Density and moisture content
When using a glass petroleum densitometer laboratory to measure density in a manual measurement system, the standard density of the oil product is determined according to the following steps:
a) Determine the oil test temperature and apparent density according to GB/T 1884 or NB/SH/T 0874;
b) Determine the standard density of oil products by referring to the table in GB/T 1885-1998 or using the calculation method provided in Appendix A;
c) Calculate the arithmetic mean of the results of each standard density measurement during the measurement period as the final standard density of the oil product.
When using a vibrating tube densitometer to measure density in a laboratory for a manual measuring system, the standard density should be determined according to the following steps:
a) Determine the oil test temperature and measurement density according to SH/T 0604;
b) Calculate the standard density of oil products according to Appendix A;
c) Calculate the arithmetic mean of the results of each standard density measurement during the measurement period as the final standard density of the oil product.
SH/T 0604-2000 Determination of Density of Crude Oil and Petroleum Products (U-tube Method)


Kyoto Electronics KEM U-shaped vibrating tube method digital density meter DA-840