Horizontal well self-guide hydraulic water jetting device and method

Abstract

The invention discloses a horizontal well self-guide hydraulic water jetting device and method. The device comprises an upper connector, a hydraulic cylinder, a connecting sleeve, a push rod, a gravity bar, a direction control ring, a rotating ring, a jetting gun assembly and a lower connector. The device is connected into a pipe string, and is lowered to a design jetting hole, and pressure in a well shaft is increased; the hydraulic cylinder moves downwards after pushed by hydraulic pressure to drive the push rod and the gravity rod to move; the gravity rod is inserted into a spiral milling groove of the rotating ring through guiding of the direction control ring, and then drives the rotating ring to rotate; the jetting gun assembly is connected with the rotating ring; and perforation operation is conducted after the angle is determined. In this way, the device is not influenced by the pipe string structure and well shaft, and the positioning mode is not affected by external environment. When pressure in the tool is increased, a self-guiding mechanism forces a jetting hole to rotate, and the positioning of the jetting hole is accurate and reliable. Jetting ineffectiveness and downhole accidents caused by dangerous formation direction can be effectively avoided, and coal bed gas recovery efficiency and gas disaster control effect are improved.

Description

technical field [0001] The invention relates to the technical field of underground gas extraction in mines, in particular to a horizontal well self-guiding hydraulic water injection device and method for coalbed gas well stimulation and gas control wells. Background technique [0002] As the development of coalbed methane advances towards complex geological conditions, in order to improve the recovery rate and development effect of coalbed methane, in the process of fracturing and increasing production of coalbed methane wells and controlling coal mine gas disasters, the preset position of hydraulic sandblasting is realized through self-guiding And other special operations have become one of the indispensable means. [0003] At present, the common solutions are mainly divided into two types, mechanical directional water jetting and cable instrument supporting directional water jetting. Among them, mechanical directional hydraulic jetting is mainly used in horizontal well op...

AI Technical Summary

Problems solved by technology

Among them, mechanical directional hydraulic jetting is mainly used in horizontal well operations. By installing eccentric components on the working tool string, relying on the gravity stroke turning torque of the eccentric component, and then controlling the rotation of the entire tool string to achieve hydraulic jetting at a preset position. The rotation torque is small, and it is greatly affected by the cleanliness of the downhole environment, the friction of the wellbore, and the friction of the tool seal assembly, which can easily cause inaccurate or large deviations in the perforation direction, and ultimately seriously affect the directional perforation direction

The directional hydraulic injection carried out by the cable instrument is mainly used in vertical wells. By using the gyroscope and the directional key to measure the azimuth of the downhole spray gun, and by continuously rotating the operation string on the ground, the operation string is finally consistent with the preset azimuth. In the actual operation In the process, due to the limitation of the operation well type, the horizontal section cannot be measured by the electronic gyroscope, and the final application range is narrow

[0004] To sum up, the two common orientation methods currently have problems such as large orientation errors and difficult operations, and it is difficult to accurately reduce the gas pressure and gas content of the coal mining face, and it is difficult to accurately achieve the goal of enhanced underground gas drainage

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