METHOD OF WELL STIMULATION BY VARYING PRESSURE Russian patent published in 1997 - IPC

FIELD: gas producing industry. SUBSTANCE: method includes shut-in of well for a time predetermined by rate of restoration of pressure at wellhead. Then, well is started operating by tubing string with reduction of pressure at wellhead down to rated value determined by preservation of the required characteristics of formation. Injected in bottom-hole formation zone of gas or gas-condensate well after its shut-in in time interval up to pressure restoration through tubing string is a portion of fluid under conditions preventing full killing of well. Then, periodically upon attaining the rated pressure, gas is alternately released from pipe and annular spaces, beginning from the last one until appearance of fluid in gas flow, or to attaining atmospheric pressure. Then, well is shut-in, and, if required, injection of fluid and cycles of gas release are repeated. EFFECT: higher production rate of gas and gas-condensate wells due to chemical treatment of bottom-hole formation zone.