主权项 |
1. A penetration fitting unit for seal-connection between a wall and a pipe passing through an opening provided in said wall, comprising:
a cylindrical sleeve internally defining a tubular passage, said cylindrical sleeve having an inlet end and an outlet end, between said inlet end and said outlet end there being at least one limit stop element protruding outwardly from the outer surface of said cylindrical sleeve, a locking ring that can be axially coupled with said cylindrical sleeve at said outlet end so as to form a seat for said wall whereby said wall upon insertion into said seat is in an abutting relationship with said locking ring and said cylindrical sleeve, a heat transfer means being interposed on said cylindrical sleeve between said limit stop element and said outlet end to allow thermowelding of said wall and said locking ring to said cylindrical sleeve without thermowelding a planar surface of said wall to said locking ring or to said limit stop element, said heat transfer means being interposed proximal to said outer surface of said cylindrical sleeve at a position extending from at least a first area at least partially overlapping the bottom of said seat for said wall and at least a second area overlapping the internal surface of said locking ring, wherein at said outlet end, said outer surface of said cylindrical sleeve is provided with a axial coupling portion for coupling with said locking ring, said heat transfer means being situated in an area between said axial coupling portion and said limit stop element to avoid said heat transfer means overlapping of said axial coupling position and thermowelding of said axial coupling portion to said locking ring, wherein said axial coupling portion has a threading and said locking ring internally has a counter-threading placed at a portion of the internal surface of said locking ring for engaging said threading of said axial coupling portion of said cylindrical sleeve, and wherein said heat transfer means is an electric wire spirally wound around said cylindrical sleeve and housed in a suitable spiral seat situated at said outer surface of said cylindrical sleeve. |