This standard specifies the basic types, technical requirements, test methods, inspection rules, storage and transportation of compressed natural gas cylinder valves. This standard is applicable to valves on compressed natural gas cylinders for vehicles with an ambient temperature of -40 to 60°C and a nominal working pressure of no more than 20MPa. GB 17926-1999 Vehicle Compressed Natural Gas Cylinder Valve GB17926-1999 Standard download decompression password: www.bzxz.net

GB17926-1999
This standard adopts the technical requirements of JIS B8246--94 "Valves for High-Pressure Gas Cylinders" (closing torque, air tightness, vibration resistance, temperature resistance, pressure resistance, safety device of cylinder valves) and relevant foreign standards in a non-equivalent manner, and tries to be consistent with foreign advanced standards in terms of technical content as much as possible, so as to adapt to international trade, technical and economic exchanges and the need to adopt international standards as soon as possible. The formulation of this standard adopts the general technical content of product quality indicators in foreign advanced standards that have been proven to be suitable for my country's situation in practice; at the same time, in order to improve the design and manufacturing level of my country's gas cylinder valve industry and ensure the reliability and safety of compressed natural gas cylinder valves, according to the provisions of GB15382--1994 "General Technical Conditions for Gas Cylinder Valves", combined with the use requirements of compressed natural gas cylinder valves, the basic types, technical requirements and test methods of the valve are specified. This standard is proposed and managed by the National Technical Committee for the Promotion of Gas Cylinder Standards. This standard is drafted by Shanghai Gas Valve General Factory. The main drafters of this standard are Hu Jinggan, Hu Houcun, Wang Minjin, Cao Shengchang and Cai Yanxin. The National Technical Committee for Standardization of Gas Cylinders is entrusted with the responsibility of interpreting this standard. 479
1 Scope
National Standard of the People's Republic of China
Valves for compression natural gas cylinders for vehicles
Valves for compression natural gas cylinders for vehiclesGB 17926--1999
This standard specifies the basic types, technical requirements, test methods, inspection rules and storage and transportation of compressed natural gas cylinder valves. This standard applies to valves on compressed natural gas cylinders for vehicles with an ambient temperature of -40~60℃ and a nominal working pressure of no more than 20MPa (hereinafter referred to as valves).
2 Referenced Standardswww.bzxz.net
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB/T1173--1995 Cast aluminum alloy
GB/T 4239---1991
1 Cold rolled stainless steel and heat-resistant steel strip
GB/T4423--1992 Copper and copper alloy drawn bars GB/T5232-1985 Processing brass-chemical composition and product shape GB8335-1998 Special threads for gas cylinders
GB/T8336-1998 Special thread gauges for gas cylinders GB8337--1996 Fusible alloy plugs for gas cylinders GB15382-1994 General technical conditions for gas cylinder valves GB 17258-1998
HG 2349--1992
Compressed natural gas cylinders for automobiles
Polyamide 1010 resin
HG/T 2902-1997
3 Basic type
Polytetrafluoroethylene resin for molding
3.1 The valve is divided into two basic types: with handwheel and without handwheel (see Figure 1). The valve should have a permanent mark for the opening and closing direction. 3.2 The valve inlet connection thread is PZ27.8, and the outlet connection thread is W21.8-14LH. 3.3 The valve should be equipped with a safety device, which should be a combination of fusible alloy plug and bursting disc. 3.4 The nominal diameter of the valve is greater than or equal to 4mm. Approved by the State Administration of Quality and Technical Supervision on December 17, 1999 180
Implemented on October 1, 2000
W21. 8 - 14 LH
4 Technical requirements
GB17926-1999
W21. 8 - 14 LH
Taper 3:25
1--Handwheel, 2-Air outlet; 3-Safety device, 4-Air inlet, 5-Valve body Figure 1
Taper 325
4.1 Materials
The materials of the main parts of the valve shall comply with Table 1. When other materials are used, their performance shall not be lower than the requirements of Table 1. Table 1
Parts name
Valve body, compression sleeve, safety cap
Fusible alloy plug
Bursting disc
Sealing gasket
Seal
HPb59-1
Fusible alloy
Stainless steel strip
PTFE
Polyamide 1010 resin
Conform to standards
GB/T4423
GB/T 5232
GB/T 1173
GB8337
GB/T4239
HG/T 2902
HG2349
4.2 Processing requirements
4.2.1 The valve body shall be forged and the surface of the valve body shall not have defects such as cracks, wrinkles, inclusions, underfilling, overburning, etc. that may damage the valve performance. 4.2.2 The valve body air inlet connection thread shall comply with GB8335. 4.2.3 The handwheel shall not have sharp edges or burrs.
4.3 Performance requirements
4.3.1 Opening and closing
Under the nominal working pressure, the opening and closing torque of the valve shall not exceed 7N·m. 4.3.2 Air tightness
Under 1.1 times the nominal working pressure, there shall be no leakage when the valve is closed or opened at any time. 4.3.3 Vibration resistance
GB 17926-1999
Under the nominal working pressure, after the valve is subjected to vibration for 30 minutes with an amplitude of 2mm and a frequency of 33.3Hz, the threaded connections on the valve should not loosen and the valve should not leak.
4.3.4 Temperature resistance
Under the nominal working pressure, the valve should not leak within a temperature range of 40 to 60°C. 4.3.5 Pressure resistance
Under 1.5 times the nominal working pressure, there should be no leakage or abnormal phenomenon when the valve is in the open state. 4.3.6 Durability
Under the nominal working pressure, the valve should not leak after 4000 times of full stroke opening and closing. 4.3.7 Safety device
The action temperature of the fusible alloy plug should be 100℃±5℃, and the bursting disc on the valve should burst at 5/3 times the nominal working pressure to relieve the valve pressure, with an allowable deviation of ±5%. The design of the air release channel of the safety device should enable the compressed natural gas cylinder for vehicles to have a qualified flow rate when undergoing a fire test in accordance with GB17258.
5 Test method
5.1 Appearance inspection
The appearance is inspected visually and complies with 4.2.1 of this standard. 5.2 Connection thread inspection
The connection thread of the air inlet is inspected using a gauge manufactured in accordance with GB/T8336. 5.3 Opening and closing test
The valve is installed on a special device, and nitrogen or air is filled into the valve inlet to the nominal working pressure. After closing it with a torque not greater than 7N·m, it is immersed in water for 1 minute, and there should be no leakage; it should be able to open when opened with a torque not greater than 7N·m. 5.4 Air tightness test
Perform according to the provisions of 5.4 of GB15382-1994. 5.5 Vibration resistance test
Perform according to the provisions of 5.5 of GB15382-1994. 5.6 Temperature resistance test
Perform according to the provisions of 5.6 of GB15382--1994. 5.7 Pressure resistance test
Perform according to the provisions of 5.7 of GB15382-1994. 5.8 Durability test
Remove the safety device of the valve, and block the port and the air outlet; install the valve on a special device, keep the valve in the closed state, fill the valve inlet with nitrogen or air to the nominal working pressure, and test according to the requirements of 4.3.6 of this standard. The opening and closing frequency of the test is 10 to 20 times/min. After the test is completed, the requirements of 5.4 of GB15382-1994 shall be followed. The results shall comply with the requirements of 4.3.2 of this standard. 5.9 Safety device action test
5.9.1 Install the valve with the rupture disc removed on a special device, place it in a tank filled with glycerine, and apply 0.4MPa of air pressure from the valve inlet. Raise the temperature to 100℃±5℃ at a rate of 2℃/min. The fusible alloy plug shall act. 5.9.2 Install the valve with the fusible alloy plug melted on a special device, apply hydraulic pressure to 5/3 times the nominal working pressure from the valve inlet, and allow a deviation of ±5%. The rupture disc shall burst and the valve shall be depressurized. 6 Inspection rules
Perform according to the requirements of 6 of GB15382-1994. 482
Marking, packaging and storage
7.1 Valve marking
According to 7.1 of GB17926--1999
2-1994.
According to GB 15382-
7.2 Packaging
7.2.1 Before packaging, the water remaining in the valve should be removed, and the outer packaging should have a moisture-proof mark. 7.2.2 The packaging should play a role in effectively protecting the valve, and the packaging form should meet the needs of transportation and stacking. 7.2.3 The packaging box should be accompanied by a product certificate, a packing list and a product instruction manual. 7.2.3.1 The content of the product certificate shall comply with the provisions of 7.2.2 of GB15382-1994. 7.2.3.2 The content of the packing list shall comply with the provisions of 7.2.3 of GB15382-1994. 7.2.3.3 The marking on the packaging box shall comply with the provisions of 7.2.1 of GB15382-1994. 7.3 Storage and transportation
Valves should be stored in a dry and clean place, and should be handled with care to prevent heavy pressure and collision. 483
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.