摘要 |
1. Plastic socket of thermoplastic material for the connection of conduit elements (1, 2) of the same or a similar material by partial melting of the socket body (5, 6 ; 12) and heat sealing of the conduit elements through heat production using electrical energy in an area of the inner wall of the socket body by means of a resistance heat wire incorporated in an electrical resistance heating element the wire of which (9, 15) consisting of a material with an at least 25 % higher temperature coefficient in the case of an increase in temperature of 100 degrés C, characterized in that the resistance wire (9) is enclosed in a jacket (16) the material of which deviatas from that of the socket body, and that the thickness of the laver thereof for wire (15) diameters up to 1 mm is at least 40 %, preferably 60 %, and is at least 20 % for larger diameters. |