A Method for Releasing Stuck in Horizontal Wells

Abstract

The present invention specifically provides a method for unclamping and unclamping a horizontal well. At the beginning of reversing the pipe string, an electronic tension gauge is used to control the pulling force on the wellhead, so that the pulling force on the wellhead is approximately equal to the suspended weight of the stuck pipe string in the well. The horizontal rotation torque is transmitted to the sticking point of the horizontal section to the maximum extent, and becomes the torque of vertical plane rotation to realize the undercutting and unstuck in the horizontal well section; when a part of the stuck pipe string is poured out in the well, then For the remaining stuck pipe strings, replace them with reverse buckle drill pipes and fishing tools for back buckling, and pull out all the stuck pipe strings. The invention is driven by a driving device, and there is no over-torque undercut phenomenon, which is safe and reliable. At the same time, the undercut tool is simple and will not complicate the drill stuck accident.

Description

technical field [0001] The invention belongs to the technical field of jam-releasing operations of drilling tools for drilling construction, and in particular relates to a method for unplugging horizontal well undercuts. Background technique [0002] Horizontal wells are a new development model for large-scale development of oil and gas fields. In the process of staged fracturing, pipe sticking often occurs, and most of them can be released in time; only a few key wells cannot be released normally. The investment cost of a horizontal well from drilling to oil production is more than 20 million yuan. If the jam cannot be solved in time, the well cannot be put into oil production in time, which brings huge economic risks to the construction service unit. [0003] At present, the reasons for pipe sticking in horizontal well fracturing construction are as follows: (1) The packer carried by the construction drilling tool does not shrink after construction, and pipe sticking is fo...

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Problems solved by technology

[0004] And the unblocking method of prior art has the following several: (1) in-well hydraulic pulling method: the hydraulic puller is lowered into the top of the deflection section of the horizontal well, pressurizes in the well from the oil pipe, makes the liquid in the oil pipe The pressure turns into a pulling force to pull the stuck tool; its main function is to eliminate the pulling force formed by the weight of the pipe string, so that all the force of the hydraulic puller is applied to the stuck point. The purpose of releasing the jam with the maximum pulling force; however, the disadvantage of this method is that once the hydraulic puller is stuck in the well, it will further make the stuck drill more complicated and difficult to deal with, so it has not been widely used

(2) In-hole hydraulic undercut method: use the downhole hydraulic undercut device, lower the tool before the window entry point, use surface pump pressure, and form a torque through the undercut device, so that the pipe string is reversed from the stuck point; Due to the unstable and unreliable performance of the hydraulic undercut device, it has not been popularized and applied, and it has only been tried on individual wells.

(3) Jammer release: Lower the jar into the horizontal section and connect it with the stuck pipe string, and lift the pipe string to form a certain pulling force. When the pulling force reaches a certain set value, the jar will instantly The accumulated energy is suddenly released to generate a large impact force, which loosens the stuck point and releases the pipe string; and in this technology, because the jar needs to be lowered into the well, its hydraulic cylinder has to withstand high temperature and high pressure. Reliability has been questioned, so it has not been widely used

This method is mainly used when the stuck point is formed on the vertical section, but when the stuck point is in the horizontal section, it is easy to deform the pipe string and make the stuck pipe more complicated

(5) Undercutting and jamming release technology: This technology is widely used and is basically suitable for undercutting and jamming in vertical wells; when undercutting in horizontal wells, since the torque on the horizontal plane must be converted into torque on the vertical plane, the It is proved that the torque of unblocking wells or highly deviated wells will exceed the maximum torque of the turntable, that is, the reverse buckle will not move. Therefore, the reverse buckle release technology is rarely used in horizontal wells

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