FIELD: mining, particularly hydraulic underground seam fracturing, namely methods and devices to create fissures in uncased horizontal or vertical well.
SUBSTANCE: device comprises a number of units having rupture discs. Each disc is characterized by independent fracturing pressure, i.e. the first unit has lesser fracturing pressure in comparison with the second unit and corresponds to predetermined interval to be treated. The units are arranged in work string or well completion pipe string so that unit having lesser fracturing pressure is located at front end thereof or in the lowermost area. Next units have fracturing pressures increasing in direction from front pipe string end. As liquid is injected via pipe string pressure is increased to value exceeding fracturing pressure of the first rupture disc to provide processing liquid contact with seam. After the first horizon treatment or fracturing said horizon may be isolated. After that pressure may be repeatedly increased in pipe string and other discs may be ruptured.
EFFECT: increased efficiency due to possibility of continuous several seam fracturing.
13 cl, 6 dwg
Authors
Dates
2008-02-27—Published
2002-12-23—Filed