Transportable gas cylinders

BS EN 17339:2020 pdf free.Transportable gas cylinders一Fully wrapped carbon composite cylinders and tubes for hydrogen.
Two cylinders shall undergo this test:
a) one in a horizontal position;
b) one in a vertical position (for tubes of length more than 3 m the vertical test is replaced by a second horizontal test).
The cylinders shall be pressurized with either air or nitrogen to 2/3 x test pressure (ph).
A suitable fire shall be created using either wood, kerosene or LPG burners. Examples of standards that contain directions to produce a suitable fire test are EN ISO 11439, CGA C 14:2005 and EN 3-1.
One cylinder shall be placed in the horizontal position with the lowest part of the cylinder approximately 0.1 m from the top of the firewood or 0,1 m from the surface of the liquid. The fire shall be capable of enveloping at least 1,6 m on each side of the centre of the cylinder and at least one end, but in no case shall the flames be allowed to impinge directly on to the pressure relief device if any.
NOTE For long cylinders, it may be necessary to have 2 fire steps/locations to follow the requirements above.
One cylinder shall be placed in an upright position (valve uppermost), with the lowest part of the cylinder approximately 0,1 m from the top of the firewood or at the surface of the liquid. The cylinder shall be exposed to total fire engulfment, but in no case shall the flames be allowed to impinge directly on to the pressure relief device if any.
The fire shall be capable of producing a temperature of at least 590 °C, measured at no more than 25 mm below the cylinder, within 2 mm.
After completion of this test the cylinders shall be destroyed (e.g. by bursting) or made incapable of holding pressure.
6.2.11.2 Criteria
The cylinder shall not burst during a period of S mm from the start of the test. Cylinders may leak through the cylinder wall or other surface at any time. It is also permissible for the pressure relief device if any to activate within 5 minutes from the start of the test. If the cylinder leaks at the connection before the 5 mm have elapsed the test shall be repeated.
6.2.11.3 Parameters to monitor and record during the test
a) Type and characteristic of the pressure relief device if any;
b) initial pressure;
c) time;
d) mode of pressure release, if appropriate.
6.2.12 Test 12 – Permeability test of cylinders with non-metallic liners
6.2.12.1 Procedure
The test shall be performed with hydrogen, or alternatively helium or helium nietuies iii gases.
One cylinder shall be pressurized with the test gas (see under ‘criteria’ below) to Pw and the valve and the junctions of the thermoplastic liner or composite with the metallic bosses or rings shall he visually checked for leaks (e.g. with soapy water (bubble test)). Any leaks shall be eliminated before proceeding with the test.
The cylinder shall then be hydraulically cycled 1 000 times from zero to 2/3 x Prn.si. The cylinder shall then be filled to 2/3 x test pressure (pij with test gas at a temperature of 15 °C.The permeability flow rate will be monitored with an appropriate method like gas sensor or mass spectrometry. The calibration method shall he described in the test report.
6.2.12.2 Criteria
The maximum permeation rate of the cylinder, X shall be recorded in mI/h/I. Finally, the acceptable value of X shall be confirmed, according to the application. The total permissible amount of permeation as calculated from all of the cylinders of the bundles/trailers/MEGCs as applicable, shall be considered in a risk assessment.
The value shall be agreed by manufacturers, owners and notified bodies and shall be indicated on the approval certificate and marked on the bundles/trailers/MEGCs.
6.2.12.3 Parameters to monitor and record
a) Test gas used;
b) cycle test medium;
c) number of cycles, achieving upper cyclic pressure;
d) cycle frequency;
e) ambient temperatures and humidity at least twice a day;
f) the rate of permeation X of the cylinder.
6.2.13.1 Procedure
The cylinder threads shall show no permanent deformation when mated with a corresponding valve or plug and tightened to 110 % of the maximum torque specified and to the procedure specified in EN ISO 13341, or as recommended in the manufacturer’s specification where this document does not apply. The internal neck thread shall be checked using gauges corresponding to the agreed neck thread to ensure that it is within tolerance.
6.2.13.2 Criteria
The threads shall remain within gauge tolerance.
6.2.13.3 Parameters to monitor and record
a) Type of valve/plug material;
b) valving procedure;
c) applied torque.
Where the torque recommended by the manufacturer differs from that specified in EN ISO 13341, this shall be additionally recorded on the marking label (see Clause 8).
6.2.14 Test 14- Shear stress calculation for parallel threads for steel liners and steel bosses
6.2.14.1 Procedure
The bigger diameter of the parallel threads shall have a tight fit and a calculated shear strength of at least 10 times the shear stress at the test pressure of the cylinder.
NOTE Examples of shear stress calculations can be found in EN ISO 9809-1 and EN ISO 9809-2.
6.2.14.2 Criteria
The calculated shear strength shall be at least 10 times the shear stress at test pressure.
6.2.14.3 Parameters to monitor and record
a) Type of threads;
b) calculated shear stress level.
Where the torque recommended by the manufacturer differs from that specified in EN ISO 13341, this shall be additionally recorded on the marking label (see Clause 8).
6.2.15 Test 15 – Neck strength
6.2.15.1 Procedure
The neck of the cylinder shall show no significant deformation and shall remain within the drawing tolerance when mated with a corresponding valve or plug and tightened to 150 % of the torque specified and to the procedure specified in EN ISO 13341 or as recommended in the manufacturer’s specification, where this document does not apply. If the neck contains a threaded insert a permeability test in accordance with Test 12 (See 6.2.12) shall be carried out after this test.
6.2.15.2 Criteria
The neck shall show no significant deformation.
6.2.15.3 Parameters to monitor and record
a) Type of valve/ plug material;
b) valving procedure;
c) applied torque;
d) parameters required in Test 13 (see 6.2.13), where applicable.
Where the torque recommended by the manufacturer differs from that specified in EN ISO 13341, this shall be additionally recorded on the marking label (see Clause 8).
6.2.16 Test 16 – Neck ring
When a neck ring is fitted, the manufacturer shall ensure that the axial load required to remove the neck ring is greater than 10 times the weight of the empty cylinder and not less than 1 000 N. The minimum torque to turn the neck ring shall be greater than 100 N.m.
6.3 Failure to meet test requirements
6.3.1 Metallic liners
Where the mechanical properties of the liner have not met the requirements of the specification, they may be treated in accordance with the appropriate clauses of the relevant standard, as listed in 5.2.1.
6.3.2 Finished cylinder
For finished cylinders the following procedure may be used for prototype testing, design variant testing and production testing.
In the event of failure to meet the requirements during prototype, design variant and production testing, re-testing shall be carried out, as follows.
a) II there is evidence of a fault in carrying out a test, or an error of measurement a second test shall be performed on the same cylinder if possible. If the results of this test are satisfactory, the first test shall be ignored.
b) If the test has been carried out in a satisfactory manner, the cause of test failure shall be identified or the batch(es) of cylinders shall be rendered unserviceable for the intended purpose. If the cause of failure is identified, the defective cylinders may be reclaimed by an approved method or shall be rendered unserviceable for the intended purpose. If reclaimed, these acceptable cylinders along with the original satisfactory cylinders shall be considered a new batch of cylinders and the prototype testing and/or batch test shall be performed again. If any test or part of a test is unsatisfactory, all the cylinders of the hatch or hatches covered by the test shall be rendered unserviceable for the intended application.BS EN 17339 pdf download.Transportable gas cylinders