Abstract: The present invention concerns an assembly of pipes, particularly but not exclusively submarine pipes, adapted to permit disconnection of a tubular member therefrom while maintaining the interior of the remainder of the assembly isolated therefrom. The assembly comprises a first pipe provided with a first tubular connection portion for coaxial connection to a second tubular connection portion of a tubular member. The tubular member is also provided with a tubular extension which is coaxial with the second connection portion and houses a closure means. The end of the tubular extension is adapted to receive the casing of a manipulator for moving the closure means from the tubular extension into the first connection portion of the first pipe to isolate the first pipe from the tubular member and permit disconnection thereof.