SKIN-EFFECT BASED HEATING CABLE, HEATING UNIT AND METHOD

摘要

The invention relates to the skin-effect based induction-resistive heating units and can be used in devices intended for prevention of paraffin-hydrate deposits formation in oil-and-gas wells and pipelines, as well as for warming up of viscous products in pipelines and vessels for the purpose of their transporting and pumping. The skin-effect based heating cable contains the center conductor, the inner insulation layer and the ferromagnetic outer conductor coaxially located around them. The inner insulation layer is made of a polymer material. The outer conductor is made in form of corrugated steel tube with the wall thickness less than three skin depths at the supply voltage operating frequency. The heating unit consists of a segment of the above described heating cable and a two-phase AC power source. The first output of the AC supply is connected to the proximal end of the center conductor and the second output ¨ to the proximal end of the outer conductor. At that at the distal end of the said cable segment, the center and the outer conductors are connected to each other. The heating method consists in implementation of the heating with the use of the skin-effect in the outer conductor of the heating cable by applying the current from an industrial electric network to the input of the above described heating unit. The invention enables to simplify using due to increase of the heating cable flexibility and due to reduce the energy consumption at its operation. 3 claims, 14 subclaims, 3 figures.