| 摘要 |
A low carryover fitting assembly for coupling tubing (64) to a device (18) having a sealing surface (16) is presented. The fitting includes a ferrule (220) having a conical head (222) for seating against the sealing surface (16). The ferrule has a conical tail (226). The ferrule (220) has an axial passage (228) that is substancially equal in diameter to the inside diameter of the tubing (64). The fitting includes a sleeve (50) having a ramped inner surface (60) that is greater in inside diameter towards the forward end of the sleeve (50) and smaller in inside towards a rearward end of the sleeve (50). The fitting also includes a coupler (70), such as a coupling nut (70). The coupler (70) has a front surface (79) that engages the head (222) of the ferrule (220) to push the head (222) against the sealing surface (16). The nut (70) has an inner ramp or shoulder (76) that engages the sleeve (50) to urge the sleeve (50) towards the head (222) of the ferrule (220) when the coupling is tightened. The tubing (64) is compressed between the tail (226) of the ferrule (220) and the tapered section (60) of the sleeve (50). The tubing (64) is compressed so that it flows to a region between the tail (226) and the ramped inner surface (60). |
