Well drilling method of multibranch well

Abstract

A new multi-branch well drilling and completion method relating to oil and geological exploration is that enters and seals a permanent positioning device 1 in the main well eye; so that the upper eye of the main well window is separated from the down well eye; After the positioning, it makes the oblique machine 6 after adjusting the tool angle on the ground is put into the main well eye, and is hang on the positioning device1. The conventional tool is put into the well to do the directionally opening window, drilling the well and putting the sleeve to fix the well and completing well. After drilling, the cowl milling machine 10 reclaims the overlapping segment of the tail pipe of the main well holes and the oblique machine 6. Repeating above steps, so it drills several horizontal branch well holes or directed branch well holes in the same main well hole, so it realizes the reliable positioning of the oblique machine. It can bear large drilling pressure and drilling torque, so it fully satisfies the opening windows, lateral drilling, milling, cowl milling and other construction sets; and it makes the main well diameter largest so that the oil production, ribbing well and oil layer reforming can perform normally. It can drill several branches in the same main well shaft and the number of branch well is not limited.

Description

Technical field: [0001] The invention relates to a novel multi-branch well drilling and completion method for petroleum and geological exploration. Background technique: [0002] A multilateral well is a well in which several wellbores are drilled at different depths in a main wellbore to exploit oil layers at different depths. The branch well technology can increase the drainage area, improve the production of oil wells, and reduce the cost of reservoir development in an all-round way. The present invention relates to a new type of drilling and completion method for multi-branch wells and its equipment. Well method. [0003] Multilateral well technology is a new drilling technology developed after directional well, sidetracking well and horizontal well technology. Different from ordinary vertical wells and directional wells, multi-branch wells drill several different branches in one main wellbore, which increases the drainage area, which is equivalent to increasing the n...

AI Technical Summary

Problems solved by technology

Most of the multi-lateral wells completed with casing for development in foreign countries are constructed in casings with a size above 95 / 8″, and the main wellbore is large; however, most of the casings produced in China are 7″, 51 / 2″ or 5″, and the main wellbore Small, using conventional whipstock technology to drill multi-lateral wells not only limits the number of branches to be drilled, but also makes tool design and construction more difficult

[0005] In addition, conventional whipstock technology has inherent problems due to its technical limitations: poor performance in terms of axial load resistance, high torque resistance, and high-pressure sealing capabilities, resulting in unreliable positioning. When the drilling tool needs to re-enter When branching the wellbore, the location of the wellbore may not be found, resulting in reentry failure, which will bring many problems to subsequent oil production, well workover and reservoir stimulation

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