| 摘要 |
<p>A union (10,110,210) for tubes having a first external wall and a second internal wall coaxial with the first to define a chamber around a central duct. The union comprises at least two seats (17,117,217) for reception each of one end of a tube to be connected. Each seat comprises a first surface (19,119,219) designed to adhere to an end segment of the first wall of a tube inserted in the seat and a second surface (20,120,220) coaxial with the first and designed to adhere to an end segment of the second wall of said tube. Between the first and second surfaces of the union there is a connection surface (21,121,221). The union comprises in it first ducts (22,122,222) which lead into said connection surfaces to provide connection between the chambers of tubes inserted in the seats and second ducts (23,123,223) which lead into spaces circumscribed by the second surfaces (20,120,220) to provide connection between the central ducts of said tubes. <IMAGE></p> |
