Moveable combination of guide rod and milling cone

Abstract

The invention relates to a moveable combination of a guide rod and a milling cone used in major repair of oilfield wells damaged by broken casings, aiming to improve success rate of milling diameter expansion of oil wells with severely broken casings. The moveable combination of the guide rod and the milling cone is characterized in that the lower segment of the guide rod is curved and the lower end of the guide rod is wedge-shaped, the outer thread segment of the upper segment of the guide rod is connected with a directional joint and a limiting ring, a pin is penetratingly arranged between the guide rod and the directional joint, the lower end face of the directional joint is located on the end face of a stepped hole, the limiting ring and the upper end face of the guide rod abut against a screwed plug, and the screwed plug is threadedly connected with an inner hole of a milling cone body; a plurality of axial grooves are evenly distributed on the upper outer-circle of the directional joint circumferentially, a roller is arranged in each axial groove; a milling-proof sleeve matching with the guide rod is fixed by the lower hole end of the milling cone body, and an O-shaped gasket is arranged between the inner hole of the milling cone body and the guide rod; and the outer cylinder surface of the milling cone body and the lower conical surface connected with the outer cylinder surface are fixed with a hard alloy layer. With the moveable guide rod and milling cone body, off-drilling in the milling process of a drill rod nib rotating along the drill rod can be avoided, and then the success rate of diameter expansion can be increased.

Description

technical field [0001] The invention relates to a movable guide rod milling cone used in the overhaul of oil field casing damaged wells. Background technique [0002] In the overhaul construction of wells damaged by casing dislocations in oil fields, it is first necessary to expand the pipe to reshape or grind and expand the casing dislocation. For wells with severe casing dislocation, because the casing at the dislocation part deviates from the original downhole casing by a large amount, it is generally first to use the drill pipe nib remade from waste drill pipe to find the channel of the dislocation part of the casing. After judging the channel where the tip of the drill pipe is inserted into the dislocation, start the turntable, and use the hard alloy welded on the outside of the nib of the drill pipe to grind and expand the dislocation of the casing, and then select the existing shaper or milling type tool for further processing. Since the tip of the drill pipe needs ...

AI Technical Summary

Problems solved by technology

Since the tip of the drill pipe needs to have a certain degree of curvature, it is easy to find the channel of the wrong part. When it rotates with the drill string during the milling process, sometimes it is not serious, and the tip of the drill pipe will be twisted off and stuck in the casing. location, which makes the overhaul construction more complicated, and cannot guarantee the success rate of milling and expansion in wells with severe casing dislocation

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