Standards related to:

GB/T 9109.5-2017GB/T 9109.5-2017

GB

NATIONAL STANDARD OF THE

PEOPLE’S REPUBLIC OF CHINA

ICS 75.180.30

E 98

Replacing GB/T 9109.5-2009

Petroleum and liquid petroleum products dynamic

measurement - Part 5: Calculation of oil quantities

(ISO 4267-2:1988, Petroleum and liquid petroleum products - Calculation of oil

quantities - Part 2: Dynamic measurement, NEQ)

ISSUED ON: MAY 12, 2017

IMPLEMENTED ON: DECEMBER 01, 2017

Issued by: General Administration of Quality Supervision, Inspection and

Quarantine of PRC;

National Standardization Administration.

Table of Contents

Foreword ... 3

Introduction ... 5

1 Scope ... 6

2 Normative references ... 6

3 Terms, definitions, symbols... 7

4 Significant digits of measurement parameters and numerical rounding ... 10

5 Preparation of basic data ... 12

6 Fuel quantity calculation formula ... 13

7 Measurement bills ... 19

8 Calculation method of oil quantity ... 22

Appendix A (Normative) Measurement data reading rules ... 32

Appendix B (Normative) Calculation method of oil volumetric pressure correction

factor ... 35

Appendix C (Normative) Hydrocarbon compressibility factor ... 37

Appendix D (Normative) Conversion of petroleum and liquid petroleum products from

20 °C density to 15 °C density ... 38

Appendix E (Informative) Air buoyancy correction factor table ... 40

Appendix F (Informative) Format and content of measurement bills ... 41

Appendix G (Normative) Conversion factor from 15 °C density to barrel/t ... 42

Petroleum and liquid petroleum products dynamic

measurement - Part 5: Calculation of oil quantities

1 Scope

This Part of GB/T 9109 specifies the oil quantity calculation method for dynamic

measurement of petroleum and liquid petroleum products (hereinafter referred to as oil);

defines the terms and symbols used in the dynamic measurement of oil products; gives

the weight in air under different measurement methods using different measuring

instruments, OR the formula for calculating the oil quantity under standard reference

conditions; provides the relevant measurement parameters, correction factors,

corresponding formulas and tables, which are involved in the calculation of the oil

quantity.

This Part only applies to the dynamic measurement of single-phase oil products.

This Part does not apply to the oil quantity calculation of liquefied petroleum gas and

stable light hydrocarbons.

2 Normative references

The following documents are essential to the application of this document. For the dated

documents, only the versions with the dates indicated are applicable to this document;

for the undated documents, only the latest version (including all the amendments) is

applicable to this standard.

GB/T 260 Test method for water in petroleum products - Distillation method

GB/T 1884 Crude petroleum and liquid petroleum products - Laboratory

determination of density - Hydrometer method

GB/T 1885-1998 Petroleum measurement tables

GB/T 4756 Method for manual sampling of petroleum liquids

GB/T 6531 Crude petroleum and fuel oils - Determination of sediment - Extraction

method

GB/T 8170 Rules of rounding off for numerical values & expression and judgement

of limiting values

GB/T 8929 Crude petroleum - Determination of water - Distillation method

4.1.1 Depending on the density reading and density conversion, keep 1 decimal place,

that is, 0.1 kg/m3.

4.1.2 Measurement of moisture content in oil (distillation method), round to two

decimal places 0.01%.

4.1.3 Temperature readings shall be kept to one decimal place, which is 0.1 °C. The

arithmetic mean of the measurement temperature is rounded to 0.25 °C.

4.1.4 When the pressure reading is in kPa, take an integer. When it is in MPa, take two

decimal places. The measurement pressure is rounded to 50 kPa (gauge pressure).

4.1.5 The cumulative volume reading of the flowmeter is rounded to 0.001 m3. The

continuous measurement of long-distance pipelines can be rounded to 1 m3.

4.1.6 The cumulative mass reading of the mass instrument can be rounded to 0.001 t;

the continuous measurement of long-distance pipelines can be rounded to 1 t.

Note: In order to ensure the consistency and accuracy of the oil quantity calculation results, the

minimum requirements for the effective digits of each measurement parameter are given above.

4.2 Numerical rounding off

4.2.1 The numerical rounding off method shall comply with the provisions of GB/T

8170. In most cases, the number of decimal places used is affected by the data source.

In the absence of other limiting factors, rounding off shall be performed, according to

the decimal places specified in Table 2. However, the data in Table 2 are not the

accuracy requirements of measuring instruments. When testing the consistency of the

calculation method with this Part, the number of displayed digits shall not be less than

10.

4.2.2 MF, Ctl, Cpl, Csw, Fa shall be rounded to the fourth decimal place, in accordance

with the provisions of GB/T 8170.

4.2.3 The oil quantity settlement value follows the requirements of GB/T 8170; the

volume value is rounded to 0.001 m3; the mass value is rounded to 0.001 t.

Example:

Volume (m3): 88256.7885, rounded to 88256.788

Weight (t): 8332.5755, rounded to 8332.576

Flowmeter factor: 1.00165, rounded to 1.0016

1.00155, rounded to 1.0016

Density (kg/m3): 834.45, rounded to 834.4

5.3 Measuring temperature

The measurement temperature of oil products shall be measured or recorded, using a

mercury-in-glass thermometer, which has a graduation value of not less than 0.2 °C,

OR other types of temperature transmitters, which are not lower than the same accuracy

requirements.

5.4 Measuring pressure

Oil measuring pressure shall be measured or recorded, using a 0.4 grade pressure gauge

or other types of pressure transmitters, which are not lower than the same accuracy

requirements.

5.5 Sampling

Oil sampling shall be carried out, in accordance with the requirements specified in

GB/T 4756 or GB/T 27867.

5.6 Density

5.6.1 Apparent density (ρt)

Density of oil at test temperature. It is usually obtained by manual or automatic

sampling, laboratory testing, OR through online measurement by a density measuring

instrument.

5.6.2 Standard density (ρ20)

Density of oil under standard reference conditions. It is usually calculated by looking

up the Table in GB/T 1885.

5.6.3 Density at 15 °C (ρ15)

The density of oil at 15 °C. It is usually converted from the density at 20 °C.

5.7 Moisture content

It is measured according to GB/T 8929; it can also be measured according to GB/T 260

and GB/T 6531. With the agreement of both parties to the trade, it may also use other

continuous automatic moisture content (or sediment) measuring instruments, which

have an accuracy level equivalent to the above method.

6 Fuel quantity calculation formula

6.1 Method overview

6.1.1 The settlement basis for oil trade is divided into weight or volume in the air.

Therefore, oil quantity calculation is also divided into two methods: gravimetric oil

quantity calculation method and volumetric oil quantity calculation method. At present,

domestically, the weight of oil products in the air is used as the basis for trade settlement.

6.1.2 The dynamic measurement of oil products is divided into two categories: basic

error method and flowmeter factor method. The oil quantity transfer agreement, which

is signed by both parties in the trade, determines whether the basic error method or the

flowmeter factor method will be used in the calculation of oil quantity.

The basic error method means that during the operation of the flowmeter, if the error is

within the allowable basic error (±0.20%) limit, the flowmeter factor MF is regarded as

1.0000, that is, the flowmeter indication error is not corrected, meanwhile the measured

oil quantity after correction of temperature, pressure, deducting moisture content, is the

delivery quantity, which is recognized by both parties to the trade.

The flowmeter factor method means that during the measurement period of the

flowmeter, the volume measured by the flowmeter is multiplied by the flowmeter factor,

after temperature and pressure correction, to obtain the gross standard volume. The

gross standard volume is deducted by the moisture content, to obtain the net standard

volume, which is used as the oil delivery quantity, as recognized by both parties to the

trade. OR multiply the net standard volume of the oil product by the standard density

of the oil product, then multiply it by the air buoyancy correction factor (Fa), to get the

net weight of the oil product in the air, as the delivery quantity. Both parties shall clarify

the specific determination method and use method of the flowmeter factor in the

handover agreement.

6.1.3 Taking the volume-weight method as an example (flowmeter factor method),

during the measurement period, record the indicated volume (Vt), which is measured

by the flowmeter under the measurement temperature and measurement pressure. Based

on the flowmeter factor corresponding to the different operating flow rates of the

flowmeter, multiply the indicated volume by the flowmeter factor MF, temperature

correction factor Ctl, pressure correction factor Cpl, to obtain the gross standard volume.

If water needs to be deducted from it, deduct it to obtain the net standard volume of the

oil, as the measurement result. OR multiply the net standard volume of the oil product

by the standard density of the oil product, then multiply it by the air buoyancy correction

factor (Fa), to get the net weight of the oil product in the air, as the measurement result.

It can also use the net standard volume of the oil, which is multiplied by the weight

conversion factor (Fw), to get the net weight of the oil in the air.

6.2 Volume settlement

6.2.1 Calculation formula

a) The gross standard volume in air is calculated according to formula (1):

formula (22). Using the flowmeter factor method, the MF is calculated or looked up

Table, according to the flowmeter factor table corresponding to the average mass during

the flowmeter measurement period.

Note that some mass flowmeter transmitters have MF configuration correction function.

The transmitter configuration MF value shall be confirmed in advance (the original

value shall be 1.0000), to prevent secondary MF correction of the flowmeter

measurement value.

6.3.4 Calculation formula of oil moisture content

msw is calculated according to formula (26):

7 Measurement bills

7.1 Measurement data requirements

7.1.1 Use standardized conditions and prescribed calculation procedures, to obtain

consistent calculation results from the same set of oil quantity data; standardize the

calculation rules for oil quantity (volume or mass).

7.1.2 The measurement bill is a written notice from the trading parties, confirming the

quantity of oil products received or delivered (including the main quality indicators),

which is the basis for the financial settlement of the trading parties.

If the ownership or custody of the oil products changes during the transfer, the

measurement bill will serve as a contract between the authorized representatives of the

relevant parties for the measurement quantity and quality inspection of the transferred

oil products.

7.1.3 Ensure that copies of measurement bills (including faxes) are clearly written,

unless the relevant parties agree to make modification or deletion on the measurement

bills. If this happens, it shall be explained and signed on this measurement bill.

Otherwise, modification and deletion on the measurement bill are prohibited.

7.1.4 If there is an error in the measurement bill, the bill shall be marked "invalid" and

a new bill shall be prepared. If the invalid measurement bill has a mechanically printed

number, then this number can be printed on the new measurement bill; the invalid

measurement bill must be clamped (or attached) to the new measurement bill, to prove

the validity of the above-mentioned printed number.

7.2 Calculation process of measurement parameters

During the oil measurement and calculation process, the order of each measurement

Appendix A

(Normative)

Measurement data reading rules

A.1 Flowmeter reading

A.1.1 For measuring stations (points) where the flowmeter is equipped with a glass

density float meter, when the measuring time is not greater than 8 hours, only the

starting and ending volume indication values of the flowmeter are recorded. When the

measurement time is greater than 8 hours, the readings at the beginning and end of

measurement and the flowmeter volume indication value every 8 hours need to be

recorded. For some measurement stations (points), record the cumulative value of the

flowmeter every 2 hours; settle it once every 8 hours.

A.1.2 For measuring stations (points) where the flowmeter is equipped with an online

density meter, the volume value indicated by the flowmeter head and the mass value

displayed by the mass instrument shall be recorded, as required by A.1.1. For some

metering stations (points), record the cumulative value of the flowmeter once every 2

hours; set it once every 8 hours.

A.2 Temperature and pressure measurement

A.2.1 The graduation value of the thermometer is not greater than 0.2 °C. The maximum

allowable error of the temperature transmitter is better than ±0.2%. The accuracy level

of the pressure gauge is not less than 0.4; the maximum allowable error of the pressure

transmitter is better than ±0.2%.

A.2.2 The temperature and pressure measurement points shall be selected closest to the

outlet of the flowmeter.

A.2.3 For loading measurement, the temperature and pressure shall be measured once,

10 minutes after the measurement starts (the oil in the tank flows through the flowmeter),

10 minutes before the measurement ends, and in the middle of the measurement. The

arithmetic mean of the three temperatures and pressures shall be taken as average

temperature and pressure of oil.

A.2.4 For shipping measurement, the temperature and pressure shall be measured 10

minutes after the measurement starts (the oil in the tank flows through the flowmeter)

and 10 minutes before the measurement ends, and once every 1 hour. Take the

arithmetic mean of each measured temperature and pressure, within the measurement

time, as the average temperature and pressure of the oil product.

A.2.5 For continuous oil measurement in pipelines, temperature and pressure

measurements shall be taken once every 2 hours. Take the arithmetic mean of four

temperature and pressure measurements, within 8 hours, as the average temperature and

pressure of the oil within 8 hours.

A.3 Sampling

A.3.1 Automatic sampling shall comply with the requirements of GB/T 27867. Manual

sampling shall comply with the requirements of GB/T 4756. The sampling location

shall be on the pipeline close to the outlet of the flowmeter. In case of dispute, the flow

rate sample shall prevail.

A.3.2 For loading measurement without automatic sampler, sampling shall be taken

once at the beginning, middle and 10 minutes before the end of measurement; the

samples shall be mixed into a combined specimen with equal volume (or mass).

A.3.3 For shipment measurement without automatic sampler, sampling shall be done

once the measurement starts and the oil in the tank flows to the sampler; then take

sample once every 1 hour (shipping flow rate is greater than 2000 m3/h) or 2 hours

(shipping flow rate is not more than 2000 m3/h). Mix the samples with equal volumes

(or masses) into a combined specimen.

A.3.4 For continuous oil measurement in pipelines, take sample once every 2 hours;

blend it into a combined specimen every 4 hours.

A.4 Determination of oil density using glass density float meter

A.4.1 The measurement method shall comply with the provisions of GB/T 1884.

A.4.2 For loading and shipping measurement, make a combined specimen during the

entire measurement process, to measure the density.

A.4.3 For continuous oil delivery measurement in pipelines, make a combined

specimen once every 4 hours. Use the arithmetic mean of the test results of the

secondary combined specimens within 8 hours as the 8-hour density measurement

result. It may also densify the number of samples within 8 hours.

A.5 Determination of moisture content in crude oil

A.5.1 The determination of moisture content of crude oil shall comply with the

provisions of GB/T 8929.

A.5.2 Make a combined specimen for the entire measurement process of loading and

shipping.

A.5.3 For continuous oil measurement in pipelines, prepare a combined specimen once

every 4 hours, to measure its volumetric (or mass) moisture content. Take the arithmetic

mean of the measured results of the secondary combined specimens within 8 hours, as

...