| 摘要 |
FIELD: oil and gas industry, selective isolation of water influxes and crossflows in well. SUBSTANCE: method can be applied for conditions of low-permeable collectors, for repairs. Lack of tightness of casing string perforated in productive layer is corrected by squeeze cementing. In correspondence with invention packer with tail part is sunk and set on pressure-tested tubing string in well, in casing string filled with fluid showing density 1.02-1.23 g/cu cm with initial acceptance above 150.0 cu m/day. Length of tail part is 20.0-50.0 m and is equal to half distance from cut of tail part to perforation interval or lack of tightness. Grouting mixture with density 1.6-1.9 g/cu cm and spreadability 20-24 cm is prepared and pumped into zone under packer, between buffer layers. Grouting mixture includes surface-active substances, rheological admixtures and mixed grouting cement, brand G. Grouting mixture is forced with technical water under working pressure of 10-32 MPa, is cured for 24-48 h at temperature between 40 and 90 C. Pressure in system is relieved to atmospheric pressure. Then packer is removed and lifted. EFFECT: enhanced efficiency and safety of cementing with versatility of used grouting mixtures. 4 cl, 6 dwg
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