The focus of the thesis is the pipeline designed to convey hydrogen from tanks to the fuel cell, in the ALSTOM FNM-HMU project. Part of the piping system is exposed at outside environment temperatures, being located at the roof of the PowerCar. Pipes could face high temperature ranges during the refuelling process, generating considerable thermal stresses. Due to this reason, the case-study includes a flexibility analysis of two different pipeline layouts, performed with an empirical test involving strain gauges and thermocouples. The aim is to verify the pipeline structural integrity considering longitudinal stresses due to gravity, temperature, and pressure loads. After an introduction about the ALSTOM H2 project, an overview on pipe design is treated, considering both theoretical models and standard norms.