Double-wall hydrogen pipeline comprising at least one system for detecting a leak at at least one coupling system, and aircraft comprising at least one such pipeline

A pipeline comprising:

• at least first and second portions,
• at least one coupling system connecting the first and second portions,
• each of the first and second portions comprising:
• an outer pipe,
• an inner pipe positioned inside the outer pipe,
• an intermediary space situated between the outer and inner pipes and containing a first atmosphere,
• at least one leak detection system configured to determine a characteristic of the first atmosphere,
• the coupling system comprising:
• at least a downstream flange ring connected to at least one of the outer and inner pipes of the first portion,
• at least an upstream flange ring connected to at least one of the outer and inner pipes of the second portion, and
• connecting elements connecting the upstream and downstream flange rings,
• wherein the coupling system comprises first and second annular seals interposed between the upstream and downstream flange rings and configured to delimit, with the upstream and downstream flange rings, a buffer space containing a second atmosphere,
• wherein the pipeline comprises at least one leak detection system configured to determine at least one characteristic of the second atmosphere,
• wherein the coupling system comprises at least one end stop to keep the first and second annular seals apart,
• wherein the first annular seal has an inside diameter,
• wherein the second annular seal is positioned inside the first annular seal and has an outside diameter,
• wherein the end stop is a circular rib secured to a first flange ring of the downstream flange ring, the circular rib having an outside diameter substantially equal to the inside diameter of the first annular seal and an inside diameter substantially equal to the outside diameter of the second annular seal, so as to provide a sealed connection between the first annular seal and the second annular seal,
• wherein the coupling system comprises at least one through-orifice passing through the upstream flange ring to cause the buffer space to communicate with one of the intermediary spaces of the first and second portions, and
• wherein the through-orifice is positioned on a second flange ring of the upstream flange ring, which is different than the first flange ring,
• wherein the coupling system comprises at least one spacer interposed between the upstream and downstream flange rings to keep the upstream and downstream flange rings spaced apart,
• wherein each spacer is a tube configured to house one of the connecting elements.