| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a plastic pipe from being connected while being twisted by preventing following turning of the plastic pipe in the fastening operation for the plastic pipe by a cap nut. SOLUTION: A coupling device is composed of a coupling main body 1 in which an inner core part 4 is projectingly provided on an external thread pipe part 3 on the side to which a plastic pipe (P) is to be connected, a split ring 5 fitted on the inner core 4 part so that the plastic pipe (p) may be pinched between it and the inner core part 4 of the coupling main body 1, and a cap nut 7 to be screwed to the external thread pipe part 3 so that the split ring 5 may be fastened, a nick part 4a for locking is provided on the outer peripheral surface of the inner core part 4, and a projecting line part 5c for locking is provided on the inner peripheral surface of the split ring 5. Coating layers 6, 8 made of fluorocarbon resin are respectively provided on the outer peripheral surface of the split ring 5 and the inner peripheral surface of the cap nut 7 to be faced to the outer peripheral surface at the time when the fastening of the split ring 5 is completed.</p> |
