DEVICE FOR TREATING WELL WALLS Russian patent published in 1995 - IPC

FIELD: mining engineering. SUBSTANCE: device has hollow casing 1, spring-loaded radial sleeve 3 mounted in its wall and having whirl chamber 4 communicating to the casing cavity through tangential holes 5. Blind tube with radial holes is axially mountable inside hollow casing 1 to attach spring-loaded radial sleeves 3. The open end of the blind tube is located in the space behind the casing. Draw out spring-loaded radial members having dielectric tips are mountable in casing 1. The device operates as follows. Working fluid is supplied through the whirl chamber to the well walls forming fan-shaped flows cleaning the walls in the cleaning mode. A part of the working fluid washes off dirt from perforation channels leading into the well cavity. The perforation channel deepening mode is characterized by pressure developed in the cavity of casing 1 enough to make sleeves 3 get out of the casing and approach tightly the perforation channel openings. Working fluid jet curled in whirl chamber 4 slides along the perforation channel walls owing to the centrifugal forces and washes out the channel walls and end face. Used up working fluid together with slime escapes in the center of channel along the whirl chamber axis and is discharged into the surrounding space outside the casing. The draw out spring-loaded radial members with dielectric tips enable electric contact to be made with the casing string in the case the draw-out members enter the perforation holes. EFFECT: wider range of functional applications. 4 cl, 6 dwg