Pressurized gas circuit-breaker pole that can be assembled and disassembled without significant loss of gas

A pressurized gas circuit-breaker pole that is operative to be assembled and disassembled without significant loss of gas, comprising a first enclosure or pole head including a first envelope having a first connecting flange with a circular orifice, said first envelope containing a first mobile assembly terminating in a coupling member coaxial with said orifice, and a second enclosure constituting an insulative column including a second envelope having a second connecting flange with a corresponding circular orifice, said second envelope containing a second mobile assembly including a link for maneuvering said first mobile assembly and having an end including a complementary coupling member for coupling said end with said coupling member, wherein said connecting flange of each enclosure is fitted with an annular elastomer seal fixed to the corresponding connecting flange and through which the corresponding mobile assembly passes, said seal of each enclosure providing, during assembly of said flanges and coupling of said internal mobile assemblies, a sliding seal along the respective mobile assemblies, and means for breaking the seal along said mobile assemblies on completion of assembly by reversible and automatic deformation of said annular elastomer seal to establish communication between said two enclosures.