LIGHTWEIGHT CEMENT-GROUTING NON-SHRINKING MORTAR Russian patent published in 2024 - IPC C09K8/467 E21B33/138 C04B28/02 C04B38/08 C04B14/02 C04B103/20 C04B103/32 C04B111/20 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, in particular to grouting mortars, intended for cementing well intervals caused by presence of poorly cemented rocks with abnormally low formation pressure, low gradient of hydraulic fracturing (not less than 0.0130 MPa/m) and moderate formation temperatures (75-90 °C). Lightweight cement-grouting non-shrinking mortar contains, wt.%: backfill portland cement grade “ПЦТ” I-G-CC-1 27.264-36.353; microcement 0.526-9.088; magnesite caustic powder “ПМК-83” 6.048-9.089; aluminosilicate microspheres Granulight-2500 1.818-9.072; glass microspheres Granulight GS 3.635-5.453; condensed microsilica “МК-85” or complex mineral additive “КМД”-Н” 1.636-7.816; plasticizer easyFLOW AF 0.061-0.182; retarder “НТФ” 0.018-0.030; grouting fluid 39.311-47.356.

EFFECT: improving the quality of well lining by producing a lightweight cement-grouting non-shrinking mortar with density of 1,300±50 kg/m³, characterized by high sedimentation resistance, shrinkage-free properties, and the expanding capacity of the stone.

1 cl, 1 tbl