Drilling method of second-spudding horizontal well

Abstract

The invention discloses a drilling method of a second-spudding horizontal well. The method comprises steps as follows: a, a drill bit with an outer diameter of 346 mm is adopted for first spudding; b, a drill bit with the outer diameter of 222 mm is adopted to complete drilling of a second-spudding vertical shaft section, a drill bit with the outer diameter of 215.9 mm is adopted to complete drilling at a second-spudding inclined shaft section and a second-spudding horizontal section, and well drifting is performed; c, a second-spudding horizontal well cementation and completion integrated string device is tripped in; d, clear water and lead slurry of cement slurry are injected, and tail slurry of the cement slurry is injected; e, 4-5 m<3> of clear water, 2-3 m<3> of a spacer fluid and 2-3 m<3> of clear water are injected; f, a potassium chloride solution is injected to replace mud, a spacer fluid is injected again, and a 41.3 mm setting ball is thrown; g, 50-60 m<3> of the potassium chloride solution is injected; h, waiting on cement setting is performed for 48 h, and second-spudding drilling of the horizontal well is completed. When an inclination angle and the physical property of a reservoir change greatly, locus adjustment in a larger range can be realized, the flexibility is high, the well cementation construction difficulty is low, and the well cementation quality is good.

Description

technical field [0001] The invention relates to the technical field of drilling engineering, in particular to a drilling method for double-opening horizontal wells. Background technique [0002] Drilling in oil and gas production mainly includes drilling engineering and well completion engineering. [0003] Drilling engineering is the drilling process from spud to drilling to the target layer of exploration and development, and the complete well footage is drilled. Drilling refers to the start of drilling with the first drill bit after entering the conduit or each layer of casing. [0004] Drilling can be divided into the first spud, the second spud, the third spud, etc. A well is drilled from zero depth, which is called the first spud, referred to as the first spud; spud after the surface casing is cemented, called the second spud, referred to as the second spud; Drilling is called the third drilling, referred to as three drilling; if the technical casing has two or thre...

AI Technical Summary

Problems solved by technology

Three-cut drilling method: there is a long intermediate completion time, a long drilling and completion cycle, and a long reservoir stimulation cycle. Due to the limitation of the small size of the completion string, it is impossible to implement large-scale space cube deep stimulation on the reservoir, and the reservoir stimulation The effect is limited, and the development cost is high. At the same time, due to the small size of the completion string, it is impossible to implement technical measures such as workover, water shutoff, and repeated fracturing in the horizontal section during later production, which is not conducive to the economical and efficient development of horizontal wells

[0010] The drilling method of the horizontal well disclosed in this patent document, by eliminating the error caused by the magnetic declination and correcting the drilling direction of the drill bit multiple times, has achieved a good coincidence rate between the drilling trajectory and the predetermined trajectory; however, there are following defects: 1. The drilling construction of the section starts after the previous cementing, and the size of the drill bit is one step smaller than that of the deviated well section. It is impossible to realize the drilling operation with the same size drill bit in the deviated well section and the horizontal section; 2. When the reservoir dip angle and reservoir physical properties occur When there is a large change, it can only be adjusted in a small range, and it is impossible to flexibly adjust the trajectory with a large range; 3. It only partially meets or achieves the purpose of the original drilling design and construction. Drilling a hydrocarbon channel in a hydrocarbon-rich reservoir, when you want to change the drilling design, but can't achieve it

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