| 摘要 |
PURPOSE: To provide an electric fusion joint which is possible in stable turning-on control and provided with a turning-on control sensor. CONSTITUTION: In an electric fusion joint 1 provided with a turning-on control sensor 5, one or more projections 3 are provided on the inner periphery of a joint opening end nonmelted in fusing and moreover near a line which is parallel to a joint axial direction and includes a position on a circumference where the sensor 5 is provided. |
