PROCEDURE FOR CLEANING PRODUCTION STRING AT CYCLIC MODE OF FLUID EXTRACTION AND CONTROL DEVICE FOR REALISATION OF THIS PROCEDURE Russian patent published in 2011 - IPC E21B37/02 

FIELD: gas-and-oil producing industry.

SUBSTANCE: for realisation of procedure surface of production string is cleaned with go-devil scraper. A lower position of the cleaning zone is fixed with a stop-anchor, while an upper position of the cleaning zone is fixed with a stop. The scraper is transferred upward with a fluid flow, and it is transferred downward under force of gravitation. Ratio between volume of the cleaning zone and volume of fluid accumulated in annular space in an accumulating phase of the cycle is established under condition of accumulated volume exceeding volume of the cleaning zone. The cleaning procedure is controlled by presence and value of shear signal of impact effect of the scraper to wellhead in the phase of pumping out. In case of emergency accumulation time is altered till achieving normal mode. An emergency signal is transmitted to an operator terminal when accumulation time exceeds a specified maximum value and when this emergency situation proceeds.

EFFECT: raised efficiency and functionality of cleaning device.

7 cl, 4 dwg