Abstract: A plastic socket pipe joint comprising a cylindrical plastic socket pipe joint body, an electric heating wire buried in the cylindrical inner surface of the plastic socket pipe joint body, and two connector pins embedded in the plastic socket pipe joint body. The lower ends of the connector pins are connected to both ends of the electric heating wire and the upper ends thereof protrude from the cylindrical outer surface of the plastic socket pipe joint body. Two recesses are formed in the plastic socket pipe joint body near the connector pins for receiving respective thermocouples. The plastic pipe joint is welded to a plastic pipe by applying current to the electric wire. The temperature of the plastic pipe joint is measured with the thermocouples so that when the temperature drops to a predetermined value, the application of current is suspended.