GB/T 12137-2025 Methods for leakage test of gas cylinders English, Anglais, Englisch, Inglés, えいご
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ICS 23.020.99
CCS H 57
National Standard of the People's Republic of China
GB/T 12137-2025
Replaces GB/T 12137-2015
Methods for leakage test of gas cylinders
Issue date: 2025-08-29 Implementation date: 2026-03-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms and Definitions
4 Principle
5 Test Conditions
6 Test Medium
7 Instruments and Equipment
8 Tested Cylinder
9 Test Methods
10 Post-Test Treatment
11 Test Records
12 Precautions During Testing
Appendix A (Normative) Conversion Method for Hydrogen-Helium Leakage Rate
Appendix B (Informative) Pressure Ratio Method for Preparation of Helium-Nitrogen Mixture
Methods for Leakage Test of Gas Cylinders
1 Scope
This document specifies the principle, test conditions, test medium, instruments and equipment, tested cylinder, test methods, post-test treatment, and test records for the leakage test of gas cylinders.
This document applies to the leakage test of gas cylinders with a nominal working pressure not exceeding 70 MPa (gauge pressure).
2 Normative References
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, subsequent amendments (excluding) or revisions to these documents do not apply. For undated references, the latest edition of the document (including any amendments) applies.
GB/T 12604.7 Non-destructive testing - Terminology - Leakage detection
GB/T 13005 Terminology for gas cylinders
GB/T 13979 Mass spectrometer leak detector
GB/T 15823 Non-destructive testing - Helium leak detection method
GB/T 18443.2 Test methods for performance of vacuum insulated cryogenic equipment - Part 2: Vacuum measurement
NB/T 47013.8 Non-destructive testing of pressure equipment - Part 8: Leakage detection
3 Terms and Definitions
The terms and definitions established in GB/T 13005 and GB/T 12604.7, as well as the following terms and definitions, apply to this document.
3.1
Tested Cylinder
A gas cylinder to be tested or being tested.
3.2
Water-Immersion Test
A test method where the tested cylinder filled with gas at a specified pressure is immersed in a water tank to check its airtightness.
Note: The water-immersion test is suitable for the overall airtightness test of the tested cylinder.
3.3
Soap Bubble Test
A test method where a testing liquid is applied to the area to be checked on the tested cylinder filled with gas at a specified pressure to check the airtightness at that location.
Note: The soap bubble test is suitable for the airtightness test of the threaded connection between the cylinder and valve, valve stem, valve outlet, safety relief device, or welded joint of the cylinder.
3.4
Leak Detection by Helium Mass Spectrum
A method where a helium mass spectrometer leak detector is used to detect trace helium gas leaked from the tested cylinder filled with gas at a specified pressure.
3.5
Pressure Accumulation Test
A method where the tested cylinder filled with gas at a specified pressure is placed in a detection chamber of known volume, and within a specified time, a helium mass spectrometer leak detector is used to detect trace helium gas leaked from the tested cylinder.
3.6
Vacuum Chamber Test
A method where the tested cylinder filled with gas at a specified pressure is placed in a detection chamber of known volume, and after the system reaches a vacuum state and stabilizes for a period, a helium mass spectrometer leak detector is used to detect trace helium gas leaked from the tested cylinder.
3.7
Sniffing Test
A method where the tested cylinder is pressurized with gas containing trace helium, and the trace helium gas is detected using a sniffer probe.
3.8
Calibrated Pressure Gauge
A pressure measuring instrument used to verify whether the indication of the working pressure gauge is accurate.
3.9
Working Pressure Gauge
A pressure measuring instrument used to display and record the pressure of the tested cylinder.
Note: The working pressure gauge includes pressure gauges and pressure transmitters (or digital pressure gauges with pressure signal output).
3.10
Capillary Standard Leak
A leak with an independent helium gas cylinder not less than 0.1 MPa, allowing trace helium gas to pass through a locally thinned tube.
Note: The helium leakage rate of capillary standard leaks ranges from 1×10⁻⁶ Pa·m³/s to 1×10⁻⁴ Pa·m³/s.
3.11
Permeation Standard Leak
A calibrated glass or quartz permeation leak after melting.
Note: The helium leakage rate of permeation standard leaks ranges from 1×10⁻⁹ Pa·m³/s to 1×10⁻⁷ Pa·m³/s.
4 Principle
The tested cylinder is pressurized with a specified gas at a constant and slow rate to the leakage test pressure, and the pressure is maintained for a specified time. The leakage of the tested cylinder at the leakage test pressure is measured using different test methods.
