GB/T 9973-2025 Test methods for permeability of carbon materials English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 29.050 CCS Q 50
People's Republic of China National Standard
GB/T 9973-2025 Replaces GB/T 9973-2006
Test Methods for Permeability of Carbon Materials
Issued on August 29, 2025
Implemented on March 1, 2026
Issued by the State Administration for Market Regulation
Standardization Administration of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Principle
5 Test Method 1 (Water Displacement Method)
6 Test Method 2 (External Gas Supply Method)
7 Precision
8 Test Report
Test Methods for Permeability of Carbon Materials
1 Scope
This document describes test methods for the permeability of carbon materials.
This document applies to the determination of permeability of carbon materials at room temperature, as well as permeability testing of blast furnace refractory materials.
2 Normative References
The following documents contain provisions that, through reference in this text, constitute essential requirements for this document. For dated references, only the edition cited applies; for undated references, the latest edition (including all amendments) applies.
GB/T 8170 Rules for rounding off numerical values and representation and judgment of limiting values
GB/T 8718 Terminology of carbon materials
3 Terms and Definitions
Terms and definitions defined in GB/T 8718 and the following apply to this document.
3.1 Permeability
A characteristic value indicating the ease with which gas passes through carbon materials under a specific temperature and pressure difference.
Note: Permeability is a property that varies with the direction of measurement (gas flow direction).
4 Principle
A gas with a certain pressure passes through the sample under laminar flow conditions, and the pressure difference at different flow rates between the two ends of the sample is measured. The permeability of the sample is calculated based on the measured values and the shape and dimensions of the sample.
Laminar flow conditions refer to the flow where the streamlines are parallel to each other, and the forming direction or use direction of the sample is usually set as the flow direction.
If the volume of gas passing through the sample within a given time is known, the permeability is calculated using Equation (1):
Where:
V — Volume of gas passing through the sample, in cubic meters (m³);
t — Time taken for the volume of gas to pass through the sample, in seconds (s);
K — Permeability of the sample, in square meters (m²);
η — Dynamic viscosity of the gas at the test temperature, in Pascal seconds (Pa·s);
A — Cross-sectional area of the sample, in square meters (m²);
h — Height of the sample, in meters (m);
p — Absolute pressure of the gas, in Pascals (Pa);
p₁ — Absolute pressure at the gas inlet end of the sample, in Pascals (Pa);
Standard
GB/T 9973-2025 Test methods for permeability of carbon materials (English Version)
GB/T 9973-2025 Test methods for permeability of carbon materials English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 29.050 CCS Q 50
People's Republic of China National Standard
GB/T 9973-2025 Replaces GB/T 9973-2006
Test Methods for Permeability of Carbon Materials
Issued on August 29, 2025
Implemented on March 1, 2026
Issued by the State Administration for Market Regulation
Standardization Administration of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Principle
5 Test Method 1 (Water Displacement Method)
6 Test Method 2 (External Gas Supply Method)
7 Precision
8 Test Report
Test Methods for Permeability of Carbon Materials
1 Scope
This document describes test methods for the permeability of carbon materials.
This document applies to the determination of permeability of carbon materials at room temperature, as well as permeability testing of blast furnace refractory materials.
2 Normative References
The following documents contain provisions that, through reference in this text, constitute essential requirements for this document. For dated references, only the edition cited applies; for undated references, the latest edition (including all amendments) applies.
GB/T 8170 Rules for rounding off numerical values and representation and judgment of limiting values
GB/T 8718 Terminology of carbon materials
3 Terms and Definitions
Terms and definitions defined in GB/T 8718 and the following apply to this document.
3.1 Permeability
A characteristic value indicating the ease with which gas passes through carbon materials under a specific temperature and pressure difference.
Note: Permeability is a property that varies with the direction of measurement (gas flow direction).
4 Principle
A gas with a certain pressure passes through the sample under laminar flow conditions, and the pressure difference at different flow rates between the two ends of the sample is measured. The permeability of the sample is calculated based on the measured values and the shape and dimensions of the sample.
Laminar flow conditions refer to the flow where the streamlines are parallel to each other, and the forming direction or use direction of the sample is usually set as the flow direction.
If the volume of gas passing through the sample within a given time is known, the permeability is calculated using Equation (1):
Where:
V — Volume of gas passing through the sample, in cubic meters (m³);
t — Time taken for the volume of gas to pass through the sample, in seconds (s);
K — Permeability of the sample, in square meters (m²);
η — Dynamic viscosity of the gas at the test temperature, in Pascal seconds (Pa·s);
A — Cross-sectional area of the sample, in square meters (m²);
h — Height of the sample, in meters (m);
p — Absolute pressure of the gas, in Pascals (Pa);
p₁ — Absolute pressure at the gas inlet end of the sample, in Pascals (Pa);
