Abstract
In response to the problems of insufficient completion fluid replacement and wellbore contamination caused by well killing fluid in the conventional completion process of ultra deep fractured sandstone reservoirs in Tarim Oilfield, a new technology for clean completion with soluble screen tubes has been developed, which includes the configuration of soluble screen tubes and release short joints in the production zone.
Soluble screen tubes, when used as tubing during well completion fluid replacement, can replace high-density well killing fluid in the lower part of the perforation section, ensuring the cleanliness of wellbore for fluid replacement; During reservoir transformation and production, the soluble sieve tube is dissolved in acid and the soluble pore plug is used to reduce fluid flow resistance. The release short section can be repaired and salvaged in sections by shearing the pin under pressure. Through experimental research on tools such as soluble sieve tubes and release short joints under pressure, the reliability of the tools has been verified.
Based on the application research in the laboratory and D304 well site, the effectiveness and feasibility of the new technology of clean completion with soluble screen tubes have been proven. In the perforation section, the soluble screen tube column effectively solves the contradiction between incomplete liquid replacement from the lower part of the column to the middle and upper parts of the perforation section and increased flow resistance from the lower part of the perforation section. Comparing the two types of tubing structures, namely tubing completion and soluble screen clean completion, it is found that the soluble screen clean completion process has significant advantages in fluid replacement, high-pressure gas flow, drainage area, daily production, etc., and the process is simple and easy to operate on site.
This technology has been applied in over 10 high-pressure gas wells in the ultra deep fractured sandstone reservoir in front of Kuche Mountain in Tarim Oilfield, with a success rate of 100%. At the same time, this technology has the advantage of integrating completion fluid replacement with well repair and salvage, providing important reference for the selection of completion technology for similar wells.
