An automatic packing device for casing

Abstract

The invention provides an automatic packing device for a casing, comprising: a body with a central flow channel, an annular groove on the outer surface of the body; an expansion sleeve installed in the annular groove , a number of scrapers uniformly distributed in the circumferential direction are arranged on the outer peripheral surface of the expansion sleeve; an isolation mechanism arranged in the annular groove for driving the scrapers to clean the inner wall of the outer casing, It includes an elastic member, a first sleeve and a second sleeve sequentially arranged on the radially outer side of the elastic member, wherein, the side wall of the body is provided with a plurality of holes that allow the fluid in the central channel to enter the The through hole of the annular groove, the expansion sleeve expands radially outward under the action of the fluid, and the isolation mechanism is configured to drive the scraper to clean the inner wall of the outer casing, so that the expansion sleeve The barrel is fully expanded to contact the inner wall of the outer casing, thereby completing the containment.

Description

technical field [0001] The invention belongs to the technical field of well cementing engineering, and in particular relates to the well cementing construction operation of a lower liner, in particular to an automatic isolation device for casing. Background technique [0002] In the process of oil extraction, the cementing operation usually uses multiple layers of casing and cement injection to achieve the purpose of supporting the well wall and isolating different formations. However, in a multi-layer casing, the diameter of the casing of the upper layer is larger than the diameter of the casing of the next layer. In addition, when the next layer of casing is used as a liner, it does not need to be tied back to the wellhead, but hangs at the lower end of the upper layer of casing and partially overlaps. The overlapping part needs to be sealed by technology, and the existing technology usually adopts cement sealing, or additionally runs a packer, so as to realize the sealin...

AI Technical Summary

Problems solved by technology

These isolation devices are usually isolated by extruding expansion sleeves or by rubber bodies, and some of them need to be isolated multiple times. The isolation efficiency is poor, the integrity of the device is poor, and the safety is low, or the structure of the isolation device is complicated. , high manufacturing cost, inconvenient operation of isolation operation, and poor control accuracy

Images