SEALING MATERIAL, PRESSING RING, COUPLING, AND VALVE

摘要

A first projection 19 is formed on the outer periphery of a bulb part 18, a second projection 20 is formed on the socket rear end of the bulb part 18, a tapered part 28 is formed with a decreasing diameter from the inner periphery of a heel part 17 to the inner periphery of the second projection 20, and a third projection 21 is formed on the tapered part 28. A first dimension B from the first.projection 19 to the third projection 21 in an inclination direction opposite to an inclination direction G of the tapered part 28 is smaller than a second dimension C from the first projection 19 to the second projection 20 in a radial direction A.