BS EN ISO 19879:2021 Metallic tube connections for fluid power and general use — Test methods for hydraulic fluid power connections.
4.3.2 Torque For all tests, except the repeated assembly and overtightening tests, tube connections and stud ends shall be tested at the required minimum torques or number of hex flats or turns from finger-tight position given in the respective connector standard, if specified. Otherwise, they shall be tested at the minimum torque values or number of hex flats or turns from finger-tight position supplied by the manufacturer. For test assembly, type 2 and type 3 adjustable stud torques shall be applied after being backed out one full turn from finger-tight, in order to test correctly the worst possible actual assembly conditions.
4.3.3 Temperature For all tests, the temperature of the hydraulic fluid shall be between 15 °C and 80 °C, unless otherwise specified in the respective connector standard.
4.4 Test report Test results and test conditions shall be reported. NOTE ISO/TR 11340 provides a method of reporting leakage.
5 Repeated assembly test
5.1 Principle Unless otherwise specified in the respective connector standard, three type 1 test assemblies shall be tested to confirm that they are capable of meeting the necessary requirements after being disassembled and re-assembled several times.
5.2 Procedure The tube connections of the straight stud connector (part A in Figure 1) and shaped connector (part C in Figure 1) shall be disassembled and re-assembled six times. Prior to each re-assembly, the tube shall be turned clockwise by 60°. On re-assembly, the nuts shall be tightened firmly, using the maximum torque values or number of turns given in the respective connector standard or by the manufacturer. All assemblies, after the first and sixth re-assembly, shall be subjected to a leakage test (Clause 6) and a proof test (Clause 7) at the test parameters specified in Table 2.
9 Cyclic endurance test
9.1 Principle Unless otherwise specified in the respective connector standard, three type 1 or six type 3 assemblies and, where applicable, six type 2 and type 4 test assemblies shall be tested to confirm that they pass a cyclic endurance test at 133 % of maximum working pressure of the connector for 1 000 000 cycles without leakage or component failure, unless otherwise specified in the respective connector standard. For flange assemblies of DN 51 and larger, and connectors for tube OD sizes 50 mm and larger, the testing of three test assemblies shall be sufficient if the design has been verified through calculation or finite element analysis.
9.2 Procedure The cyclic endurance test shall be conducted in accordance with the requirements specified in Table 6.
9.3 Re-use of components Parts that pass this test shall not be tested further, nor used for actual service or returned to stock.BS EN ISO 19879 pdf download.