Design Strategy and Qualification of Metal Flexible Hoses for >10,000 PSI Application per ASME B31.3

Abstract There is a need for metallic lines which are flexible in a pressurized or non-pressurized state for high pressure for various industries. Some of the main reasons for users to prefer flexible lines are to accommodate tolerances during install, and also to facilitate movements in non-pressurized states without the need for their prior disconnection, thus reducing significantly the maintenance period. This paper will discuss an approach which was taken to qualify the design for a flexible line with pressure ratings in the 10,000 PSI range. The mechanical design of this line was done based on EN14585:2024. This newly updated EN standard is harmonized to PED and offers alternatives for calculation and/or experimental design methods for flexible metallic lines. For some markets, there was an additional need to qualify the design of such lines per ASME B31.3 for High Pressure Fluid Service. For this, the flexible lines were considered as an unlisted component and, to substantiate the pressure capability of the lines, it was decided to use the performance testing approach from ASME B31.3, Section K304.7.2. For lifetime evaluation, a testing program was created with an experimental method with guidance from ASME Section VIII, Division 3. The paper will dive on how the test parameters were defined and the tests performed to substantiate the pressure capability of the design.