Patent ID: 8714599

Claim:
A sealing joint of two opposing faces disposed at port ends or port shoulders of pressure vessels, pipes or tubes, or pipe or tube fittings to be jointed for holding or conveying fluid medium or power, comprising an opposing face (called a toothed surface) with one or more microsawtooth rings used as seating circles, and the other full plain opposing face (called a plain surface) used as a seated surface, wherein the crest of the microsawtooth ring is a cutting edge whose corner or whose crest angle is about 90°˜120°, the tooth height Z t of the microsawtooth ring is about 10˜20 times the roughness R a of the seated surface or the plain surface, and the ratio of the tooth pitch X s to the tooth height Z t of the microsawtooth ring equals 20˜500 to provide for the toothed surface fastened tight on the plain surface a microcosmic line contact followed by a surface contact protecting the line contact thereon from disappearing.