Standards related to:

GB/T 1885-1998**GB/T 1885-1998: PDF in English (GBT 1885-1998) **

GB/T 1885-1998

GB

NATIONAL STANDARD OF THE

PEOPLE’S REPUBLIC OF CHINA

ICS 17.020

E 08

eqv ISO 91-2:1991

Replacing GB/T 1885-83(91)

Petroleum Measurement Tables

[Including No.1 Amendment]

ISSUED ON: JUNE 17, 1998

IMPLEMENTED ON: MARCH 1, 1999

Issued by: State Bureau of Quality and Technical Supervision

Table of Contents

Foreword ... 3

No.1 Amendment ... 5

ISO Foreword ... 6

1 Scope ... 7

2 Normative References ... 7

3 Definitions ... 7

4 Compositions of Petroleum Measurement Tables ... 8

5 Application and Example of Petroleum Measurement Table ... 9

Appendix A (Prompted) Examples of Petroleum Measurement Tables ... 13

Appendix B (Prompted) Calculation Flowchart of the Petroleum Measurement Tables

... 21

Petroleum Measurement Tables

1 Scope

This Standard specifies methods for converting glass petroleum densitometer readings

(observed density) obtained at non-standard temperatures into density at standard temperatures

(standard density) and volume correction factor.

This Standard applies to crude oil, lubricants and other liquid petroleum products.

The standard temperature specified in this Standard is 20°C.

The thermal expansion data of the oil used in the preparation of petroleum measurement tables

in this standard is consistent with ISO 91-1.

NOTE: When compiling the petroleum measurement tables, the thermal expansion of glass used to

correct the density meter reading is consistent with ISO 91-1, which is also 23×10-6°C-1, which is slightly

lower than the conventional value quoted in ISO 1768 (25×10-6°C-1), but under the actual maximum

temperature difference, the difference between these two s has little effect on the correction result. If both

parties to the trade agree that the impact of this error shall be considered, 0.000002ρt' (t-20) can be

subtracted from the density meter reading before checking the standard density meter, where ρt' is the

glass density meter reading and t is the test temperature.

2 Normative References

The following standards contain provisions that form part of this Standard by reference. Unless

otherwise expressly stated in the standard, the following referenced standards shall be currently

valid standards.

GB/T 1884 Crude Petroleum and Liquid Petroleum Products - Laboratory Determination

of Density - Hydrometer Method

ISO 91-1 Petroleum Measurement Tables – Part 1: Tables Based on Reference

Temperatures of 15°C and 60°F

ISO 1768 Glass hydrometers – Conventional value for the thermal cubic expansion (for

used in the preparation of measurement tables for liquids)

3 Definitions

For the purposes of this Standard, the following definitions apply.

3.1 Test temperature (t’)

The temperature of the liquid specimen at which the density meter reading is taken, in °C.

3.2 Observed density (ρt')

The reading of the glass density meter in the liquid specimen at the test temperature, in kg/m3

or g/cm3.

3.3 Density at 20°C (ρ20)

The density at the standard temperature of 20°C, in kg/m3.

3.4 Temperature of measurement (t)

The temperature of the oil in the oil storage container or pipeline at the time of measurement,

in °C.

3.5 Volume at 20°C (V20)

The volume at the standard temperature of 20°C, in m3.

3.6 Volume correction factor (VCF)

The ratio of the volume of oil at standard temperatures to its volume at non-standard

temperatures.

4 Compositions of Petroleum Measurement Tables

In the calculation of oil volume, it is recommended to use the following petroleum measurement

tables or calculation programs (see Appendix A for examples).

4.1 Standard density tables

Table 59A – Standard Density Table of the Crude Oil

Table 59B – Standard Density Table of the Product

Table 59D – Standard Density Table of the Lubricant

NOTE: If the density entered in the above table is not the observed density measured by a glass

densitometer, the above standard density table must not be used directly. Generally, the density value

must be converted into the observed density in this Document and then the table is looked up or calculate

according to the calculation program corrected by the glass density meter is omitted.

4.2 Volume correction factor tables

Table 60A – Volume Correction Factor Table of the Crude Oil

Table 60B – Volume Correction Factor Table of the Product

by a glass petroleum density meter at 40°C is 753.0 kg/m3. Find the standard density of the

petroleum product.

a) The product shall check Table 59B -- Standard Density Table of the Product;

b) The observed density range where the observed density of 753.0 kg/m3 located is

733.0~753.0 kg/m3;

c) Find 753.0 kg/m3 in the observed density column and 40°C in the temperature column.

The intersection number between the two is 770.0 kg/m3, which means the standard

density of the crude oil is 770.0 kg/m3.

EXAMPLE 2: It is known that the observed density of a certain crude oil measured by a glass

petroleum density meter at 40°C is 805.7 kg/m3. Find the standard density of the crude oil.

a) Crude oil shall check Table 59A -- Standard Density Table of the Crude Oil;

b) The density range where the observed density of 805.7 kg/m3 located is 790.0~810.0

kg/m3;

c) If there is no observed density value corresponding to 805.7 kg/m3 in the observed density

column, and it is between 804.0~806.0 kg/m3, the interpolation method shall be used.

Look up the table and find that at a temperature of 40°C, the observed density is 804.0

kg/m3 and its corresponding standard density is 818.7 kg/m3; at the same temperature,

the observed density is 806.0 kg/m3 and its corresponding standard density is 820.6 kg/m3,

using the interpolation method to obtain a change in standard density of (820.6 kg/m3-

818.7 kg/m3)/(806.0 kg/m3-804.0 kg/m3)=0.95 corresponding to a change in observed

density of 1.0kg/m3, from which the standard density of such crude oil is 818.7

kg/m3+(805.7 kg/m3-804.0 kg/m3)×0.95=820.3 kg/m3.

EXAMPLE 3: It is known that the observed density of a certain lubricant measured with a glass

petroleum density meter at 32°C is 986.0 kg/m3. Find the standard density of the lubricant.

a) Lubricant shall check Table 59D - Standard Density Table of the Lubricant;

b) The density range where the observed density of 986.0 kg/m3 located is 980.0~1000.0

kg/m3;

c) Find 986.0 kg/m3 in the observed density column and 32°C in the temperature column.

The intersection number between the two is 993.3 kg/m3, which means the standard

density of the oil is 993.3 kg/m3.

5.2 Application of volume correction factor table

5.2.1 Application procedures

Given the standard density of an oil product, the procedures to convert the volume of the oil

product at measurement temperature corrected to volume correction factor of the standard

volume are as follows:

a) Select the volume correction factor table of the corresponding oil product according to

the oil product type;

b) Determine the density range of the standard density in the volume correction factor table;

c) Find the known standard density value in the standard density column, and find the

measurement temperature value of the oil product in the temperature column. The

intersection number between the two is the volume correction factor for the oil product

to be corrected from the measurement temperature to the standard temperature.

If the known standard density is between two adjacent standard densities in the standard density

row, there is no need to use interpolation; and only the volume correction factor corresponding

to the closer standard density value shall prevail. The temperature value does not need to be

interpolated, only the closer temperature value is used to look up the table.

5.2.2 Example

EXAMPLE 1: It is known that the standard density of a certain petroleum product is 762.0

kg/m3. Find the volume correction factor to correct the volume of the oil product at 40°C to the

standard volume.

a) The product shall check Table 60B - Volume Correction Factor Table of the Product;

b) The density range where the standard density of 762.0 kg/m3 located is 750.0~770.0

kg/m3,

c) Find 762.0 kg/m3 in the standard density column and 40°C in the temperature column.

The intersection number between the two is 0.9764, which is the volume correction factor

to correct the oil volume at 40°C to the standard volume.

EXAMPLE 2: It is known that the standard density of a certain crude oil is 824.5 kg/m3. Find

the volume correction factor to correct the volume of the oil product at 40°C to the standard

volume.

a) The crude oil shall check Table 60A - Volume Correction Factor Table of the Crude Oil;

b) The density range where the standard density of 824.5 kg/m3 located is 810.0~830.0

kg/m3;

c) If there is no standard density value corresponding to 824.5 kg/m3 in the standard density

column, and it is between 824.0 kg/m3 and 826.0 kg/m3, the closest standard density

value 824.0 kg/m3 shall prevail. Check The intersection number at the temperature of

40°C is 0.9819. This value is the volume correction factor of the crude oil to correct the

volume at 40°C to the standard volume.

EXAMPLE 3: It is known that the standard density of a certain lubricant is 892.0 kg/m3. Find

......

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