Lifting and rotating back-off tool

Abstract

The invention relates to the technical field of oil and gas field downhole well repair tools, and particularly relates to a lifting and rotating back-off tool. The lifting and rotating back-off tool comprises an upper connector, a mandrel, a pressing cap, an outer cylinder, a ratchet cylinder, a guide rod and a supporting ring, wherein the mandrel comprises a connecting section and a transmissionsection which are sequentially and fixedly mounted together from top to bottom; the upper connector with the upper end located above the connecting section is fixedly mounted on the outer side of theupper end of the connecting section; the outer side of the upper portion of the connecting section corresponding to the lower end of the upper connector is sleeved with the pressing cap; a first annular table is arranged on the inner side of the upper end of the pressing cap; and a second annular table is arranged on the outer side of the lower end of the connecting section corresponding to the lower end of the pressing cap. The lifting and rotating back-off tool is reasonable and compact in structure and convenient to use, through cooperation of the guide rod and a guide rail, the lifting force of a pipe column is converted into radial torque, and thus back-off of the lower portion of the pipe column is achieved; and by forming an inclined upper inclined hole which is low in left and highin right, the ratchet cylinder is made to rotate anticlockwise when the pipe column is lifted up and rotate clockwise when the pipe column is put down, and the lifting and rotating back-off tool hasthe characteristics of being efficient, stable and capable of saving time and labor.

Description

technical field [0001] The invention relates to the technical field of downhole workover tools in oil and gas fields, and relates to a lifting and rotating undercut tool. Background technique [0002] With the continuous deepening of oilfield development, the wellbore conditions are deteriorating day by day, and the pipe string is stuck due to casing deformation, scaling, failure of the large-diameter tool unsealing mechanism in the pipe string, falling objects in the annulus, and improper fracturing measures. Phenomena happen from time to time. In the case that activities and shocks are ineffective for unblocking, the oil pipe above the stuck point becomes the necessary way for the string to be unstuck, and its efficiency directly affects the overhaul cycle and overhaul cost. At present, the commonly used methods for pipe string undercutting in case of jamming mainly include the following: one is to undercut the stuck point by undercutting the drill pipe; the other is to u...

AI Technical Summary

Problems solved by technology

[0003] The present invention provides a lifting and rotating undercutting tool, which overcomes the above-mentioned deficiencies in the prior art, and can effectively solve the problems of complicated and time-consuming and laborious undercutting and unblocking procedures of existing downhole workover tools

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