抄録
While a lot of commercially available knife-edge bakable flanges interchangeable with ConFlat type sealing system have been widely circulated and applied in UHV apparatus, their compatibility is occasionally missed in mating flanges with a nominal outer diameter of 305 mm owing to the difference of detailed dimensions between JVIS 003 and ISO 3669 standards; the dimension of gasket end in JVIS 003 is 0.3 mm larger than that of ISO 3669. In the combination of a flange of ISO 3669 with a gasket of JVIS 003, the outer rim of the gasket is larger than the gasket end on flange. On the contrary, the combination of a flange of ISO with a gasket of ISO 3669 makes a gap of approximately 0.6 mm at its maximum between the gasket end on the flange and outer rim of the gasket. Influence of this mismatching in dimensions on sealing performance was studied experimentally. While combinations required a relatively higher tightening torque, reliability in sealing was not loosed under careful tightening.
