GB/T 34510-2017Liquefied natural gas cylinders for vehicles (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing authority shall not be held responsible for identifying any or all such patent rights.

This standard was proposed by and is under the jurisdiction of the National Technical Committee on Gas Cylinders of Standardization Administration of China (SAC/TC 31).

Drafting organizations: Chart Cryogenic Engineering Systems (Changzhou) Co., Ltd., Beijing Tianhai Industry Co., Ltd., Zhangjiagang Furui Special Equipment Co., Ltd., Zhangjiagang CIMC Sanctum Cryogenic Equipment Co., Ltd., Dalian Boiler and Pressure Vessel Inspection Institute, China Special Equipment Inspection and Research Institute, Sichuan Air Separation Equipment (Group) Co., Ltd.

Main drafters: Xu Huixin, Li Zhaoting, Zhang Baoguo, Gu Haibo, Yi Xilang, Pan Huajun, Yin Jinsong, Cai Hao, Huang Qianghua, Han Bing, Wang Yanhui, Chen Zuzhi, Wang Lian, Yao Xin, Zheng Renzhong, Liu Shouzheng.

1 Scope

This standard specifies the terms and definitions, symbols, types and basic parameters, materials, design, manufacture, test methods, inspection rules, marking, packaging, transportation, storage, product certificates, product instruction manuals, batch inspection quality certificates and rules of use for liquefied natural gas (LNG) cylinders for vehicles (hereinafter referred to as cylinders).

This standard applies to refillable, welded, insulated cylinders used as automotive fuel tanks under normal ambient temperature (-40 °C to 60 °C), with LNG as the stored medium, a design temperature not higher than -196 °C, a nominal volume of 150 L to 500 L and a nominal working pressure of 0.8 MPa to 3.5 MPa.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 228.1, Metallic materials - Tensile testing - Part 1: Method of test at room temperature

GB/T 229, Metallic materials - Charpy pendulum impact test method

GB/T 1804, General tolerances - Tolerances for linear and angular dimensions without individual tolerance indications

GB/T 2653, Bend test methods on welded joints

GB/T 7144, Coloured cylinder mark for gases

GB/T 9251, Methods for hydrostatic test of gas cylinders

GB/T 12137, Methods for leakage test of gas cylinders

GB/T 13005, Terminology of gas cylinders

GB/T 13550, Molecular sieve 5A and its determination

GB/T 15384, Designation for gas cylinders

GB/T 17925, Standard practice for X-ray digital radioscopic examination of cylinder welds

4 Types and basic parameters

4.1.1 The cylinder is of horizontal construction.

4.1.2 The product model of the cylinder is designated in accordance with GB/T 15384.

4.2.2 The static evaporation rate of cylinders with a nominal working pressure of 1.0 MPa to 1.6 MPa is as specified in Table 2. The static evaporation rate of cylinders with other nominal working pressures is specified in the design drawings.

5 Materials

5.1.1 The material of the inner vessel shall be austenitic stainless steel and shall meet the requirements of GB/T 24511 and other material standards. Its chemical composition and mechanical properties shall be not lower than those specified in Table 3 and Table 4. Where materials of foreign designation are used, they shall comply with 2.2 of TSG R0006-2014.

5.1.5 The materials of the inner vessel shell and heads shall be re-inspected for chemical composition by heat number and for mechanical properties by batch number. Materials that pass the re-inspection shall be marked with a chlorine-free and sulfur-free marker.

5.1.6 The material of the outer shell shall be austenitic stainless steel.

6 Design

6.1.1 The cylinder consists of an inner vessel, an outer shell, the thermal insulation layer and the valve and piping system in the interspace.

6.3.1 The wall thickness of the outer shell and its heads shall be designed so that the allowable external pressure is not less than 0.21 MPa.

6.4.1 Longitudinal and circumferential welded joints shall be full-penetration butt joints.

6.5.1 The piping system shall provide liquid filling, liquid discharge, automatic and manual pressure relief, excess-flow limitation, pressure indication and liquid level indication. Valves shall be marked with the flow direction of the medium, and stop valves with their opening and closing directions.

6.5.7 The inner vessel shall be fitted with at least two safety valves, whose inlet pipes shall be connected directly to the gas-phase space of the inner vessel.

6.6 The cylinder shall have sufficient safety space. When filled with LNG at a saturated vapour pressure of 0.8 MPa (gauge) and with a safety valve set pressure of 1.6 MPa, the safety space shall be at least 10% of the total volume of the inner vessel.

6.7 The cylinder shall limit filling automatically, so that when it is refilled with any residual quantity of LNG the actual safety space is consistent with the design value. The test method is given in Annex D.

6.8 The hold time of the cylinder shall be not less than 5 days.