FIELD: oil industry; cleaning equipment of oil-and-gas pipe lines; maintenance of thermal conditions in pipe lines for avoidance of wax liver formation. SUBSTANCE: method includes heating the pipe line by introducing heating cable; prior to introducing the heating cable, length of zone of expected wax accumulation, length of heating cable and temperature of heating of this cable shall be determined in the course of preparation work; temperature of cable heating depends on rate of flow of liquid in pipe line, melting point of heating cable insulating material and percentage of wax in oil. Power required for heating is regulated by operating time of heating cable and its temperature which is maintained over entire length of working portion of heating cable by at least 5 C above wax melting point depending on change in surrounding temperature. Device proposed for realization of this method has cleaning member mounted in pipe line and made in form of heating cable connected to power supply source. Cable is provided with at least two heating elements insulated from each other and placed in insulating envelope. At one end they are connected to power supply source and at other end they are interconnected and insulated; ratio of electrical resistance of heating elements is selected between 1.0 and 10.0. EFFECT: enhanced efficiency of cleaning. 9 cl, 8 dwg
