Washable well type gradual unpacking packer

Abstract

The invention relates to a washable well type gradual unpacking packer, which comprises an upper joint, a central tube, an upper working cylinder, a well-cleaning working cylinder, a well-cleaning piston, a rubber cylinder component, a balance piston, a fixing piston, a release piston, a snap spring component, a release cylinder, an outer working cylinder and a lower joint. The washable well type gradual unpacking packer is characterized in that the upper end of the rubber cylinder component is provided with a separating plate, the balance piston is arranged between the periphery of the upper part of the well-cleaning working cylinder and the upper working cylinder, a limiting chute is arranged outside the balance piston, the upper working cylinder is provided with a block pin, and the inner end of the block pin is arranged in the limiting chute; the upper part of the balance piston is thin-walled and cylindrical and is uniformly provided with a plurality of long slots to form a plurality of elastic claws, the inner side face of the upper end of each elastic claw is provided with a positioning boss, and the peripheral surface of the well-cleaning working cylinder is provided with an annular positioning boss; and the outer surfaces of the elastic claws on the upper part of the balance piston are smoothly matched with an inner ring of the upper working cylinder in a sliding way. The invention has the positive effects that the lifting load can be reduced during well repair, the gradual unpacking can be realized, the safety of ground equipment can be ensured, the operating efficiency can be increased, the oil production capacity can be improved, and the packer can be used safely and reliably due to the balance piston when the upper sleeve pressure is higher than the lower sleeve pressure.

Description

technical field [0001] The invention belongs to a packing device for oil production, water injection and well washing of oil production wells, in particular to a washable well-washing type step-by-step unsealing packer. Background technique [0002] The packer is an essential downhole tool for oil testing, oil production, water injection and reservoir stimulation in oil fields. As the oil field has been exploited for many years, the pressure of the downhole reservoir has decreased. In order to improve the oil recovery capacity, the layered water flooding process is adopted. During water injection, multi-layer packers need to be configured downhole for layered water injection. However, during workover, downhole tools and multi-layer packers need to be raised. Since the multiple packers are connected in series, the frictional force of the rubber sleeve on the casing is superimposed. If the total load exceeds the pulling force of the surface operating machine, it will cause d...

AI Technical Summary

Problems solved by technology

Since the multiple packers are connected in series, the frictional force of the rubber sleeve on the casing is superimposed. If the total load exceeds the pulling force of the operating machine on the well, it will cause danger to the equipment on the well and affect the normal operation of the equipment. Therefore, the applicant has developed a A packer that can be unsealed step by step to realize multi-layer water injection

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