# 2012 Barcelona
In order to evaluate the deformability of the whole polyethylene (PE) piping system for city-gas supply, tensile tests were conducted at the various tensile-velocities and environmental temperatures for the test specimens. They consist of commercial PE pipes and a socket-type of an electro-fusion (EF) fitting having an outer diameter of 60 mm and the SDR value of 11, which their axial fusion-bonded lengths were intentionally controlled at the target values using a masking tape. The critical fusion-bonded length in axial not to break at the fitting was calculated using the equilibrium of force based on the test results. As a result, the critical length tended to become longer as increasing tensile-velocity and as decreasing environmental temperature. It was also concluded that the PE piping system in Japan has a sufficient deformability against a typical earthquake by comparing the minimum fusion-bonded length specified in corresponding Japan industrial standard (JIS) K 6775-3 with the experimental results in this study.