Description

   At the present moment, most of the oil output in Russia made with electrically driven centrifugal pumps. Over 60% of wells is equipped with these pumps now.

  A. Arutyunov and V. Dolgov started development of rodless pumps in our country. A. Arutyunov based later the company REDA. Industrial samples of centrifugal pumps were designed in the design office OKKB “KONNAS”.  At the time of active introduction (60^th years of 20^th century), depth of installation was 300 up to 1200 m.  In process of development of installations, its depth always increased and, therefore, conditions of operation became worse. Now, typical depth of installation of centrifugal pump in Western Siberia is 2200-2800 m. Formation fluid, mechanical impurities are removed intensively and increased output of associated gas follows from the oil layer.  All these factors are difficult for installation of a pump and power cable. According the data of the company “NOVOMET-PERM”, usual temperature of centrifugal pump at operation mode is 126-128^oC (oil fields Gazpromneft-Hantos). These conditions are critical for usual cables with insulation of copolymer propylene.

  The main reasons for taking the cable out of use are:

 - overheating with damage of insulation and reduction of radial thickness to critical dimension, less than 2 mm;

- intrusion of associated gas under insulation that causes breaking of insulation when rising the equipment.