CONNECTING SLEEVE OPERATING AS HEATER Russian patent published in 1998 - IPC

FIELD: oil and gas production industry. SUBSTANCE: this can be used to prevent formation of paraffin plugs. Device has following components: integral tubular body with upper and lower thread, electric power input connections, thermal sensor on internal surface of body wall. Thermal sensor is made in the form of multilayer coating incorporating thermal-insulating layer of zirconium, electric-insulating layer of aluminium oxide and layer of electric-conducting ceramics. This layer of electric-conducting ceramics is used as operating heating element. When source of alternating current is switched on, current is supplied through input connections to operating heating element. Electric-conducting ceramics is being uniformly heated. Application of aforesaid device improves heating efficiency and reliability of performance. EFFECT: higher efficiency. 1 dwg