| 摘要 |
<p>PURPOSE:To prevent draft of a tubular body due to screwed torque of a piping material by inserting this tubular body provided with an internal thread into a coupling body via an insulating resin layer, and installing an almost tubular engaged member provided with an engaged projection strip lying along each end face of the coupling body and the insulating resin layer. CONSTITUTION:In a pipe coupling A formed two thread parts 11 and 12 on each inner circumferential surface at both ends of an iron coupling body 1, a first thread part 11 is made up of directly threaded, while a second thread part 12 is installed by way of inserting a copper tubular body 15 with an internal thread on the inner surface at a time when an insulating resin layer 14 being integral with a resin core 13 as one body is formed by means of injection molding. In addition, a tubular engaged member 17 is attached to a peripheral surface at the side of the second thread part 12 tightly by means of thread connection, and an engaged projection strip 17a projectingly installed toward the inside from an end edge of this engaged member 17 is engaged with each end face of the insulating resin layer 14 and the tubular body 15. Subsequently an elastic sealant 18 is filled up in space between the engaged projection strip 17a, the insulating resin layer 14 and the tubular body 15, whereby sealability is secured.</p> |
