ISO 9809-1:2019 pdf free download – Gas cylinders一Design, construction and testing of refillable seamless steel gas cylinders and tubes一 Part 1: Quenched and tempered steel cylinders and tubes with tensile strength less than 1 100 MPa.
11 Tests/examinations on every cylinder
11.1 General
During production, the examinations specified in Z and A shall be carried out on all cylinders.
Following final heat treatment, all cylinders, except those selected for testing under Clause 10, shall be subjected to the following tests:
— a hydraulic proof pressure test in accordance with 11.2.1 or a hydraulic volumetric expansion test in accordance with 11.2.2. Test method requirements are given in 11.2. Additional guidance for these test methods and equipment control (calibration and maintenance) can be found in Iso 18119. The purchaser and manufacturer shall agree on which of these alternatives shall be carried out;
— a hardness test in accordance with 11.3
— a leak test in accordance with 11.4
— a water capacity check in accordance with 11.5.
11.2 Hydraulic test
11.2.1 Proof pressure test
The water pressure in the cylinder shall be increased at a controlled rate until the test pressure, Ph’ 15 reached within a measuring tolerance of 0/+3 % or +10 bar, whichever is the lower.
The cylinder shall remain under pressure, Ph’ for at least 30 s to establish that the pressure does not fall and that there are no leaks. During the period that the cylinder is under test pressure, it shall be visible (including the base) and remain dry. After the test, the cylinder shall show no visible permanent deformation and no trace of moisture implying leakage.
11.2.2 Volumetric expansion test
The water pressure in the cylinder shall be increased at a controlled rate until the test pressure, Ph’ iS reached within a measuring tolerance of 0/+3 % or +10 bar, whichever is the lower.
The cylinder shall remain under pressure, Ph’ for at least 30 s and the total volumetric expansion measured. The pressure shall then be released and the volumetric expansion re-measured.
The cylinder shall be rejected if it shows a permanent expansion (i.e. volumetric expansion after the pressure has been released) in excess of 10 % of the total volumetric expansion measured at the test pressure, Ph•
The total and permanent expansion readings shall be recorded, together with the corresponding serial number of each cylinder tested, so that the elastic expansion (i.e. total expansion less permanent expansion) under the test pressure can be established for each cylinder.
11.3 Hardness test
A hardness test in accordance with ISO 6506-1 (Brinell), ISO 6508-1 (Rockwell) or other equivalent methods, shall be carried out by the manufacturer. The hardness values thus determined shall be within the limits specified by the cylinder manufacturer for the material, dependent upon the heat treatment used for the production of the cylinder and the intended gas service (e.g. embrittling gases).
For tubes the hardness shall be measured and recorded at four diametrically opposed points on at least three circular cross-sections distributed over the whole parallel length of each tube at intervals not greater than 3 m. The results on each circular cross-section shall be within the minimum—maximum tensile strength range guaranteed by the manufacturer. The values may be plotted on a diagram to identify their position.