A radial horizontal well sealing device, drilling equipment and drilling method

Abstract

The invention provides a radial horizontal well sealing device, drilling equipment and drilling method, and relates to the technical field of geological drilling equipment. Drilling mechanism; the sealing element is an active rolling dynamic seal structure, which is arranged between the sealing shell and the injection pipe; both the rotary drilling mechanism and the power feeding mechanism use high-pressure jet fluid as the power source to transmit rotational power and Feed power; drilling equipment includes tubing, steering gear, jet drill bit and sealing device. The sealing device of the present invention changes from a static friction seal to a dynamic friction seal, and from a passive seal to an active seal. It has the advantages of reducing drilling costs, long equipment life, and high drilling efficiency. It is also suitable for high-temperature and high-pressure formations and can avoid the failure of traditional static friction seals. .

Description

technical field [0001] The invention relates to the technical field of geological drilling equipment, in particular to a radial horizontal well sealing device, drilling equipment and a drilling method. Background technique [0002] As the development of oil and gas fields enters the middle and late stages, most of the remaining oil reservoirs are low permeability, heavy oil, thin oil layers and fractured oil and gas reservoirs. Radial horizontal wells, full name ultra-short radius radial horizontal wells, also known as ultra-short radius horizontal wells. , Lower crude oil extraction cost has become the leading technology of crude oil extraction in the world. Radial horizontal well technology includes two processes of casing window opening and bottom drilling. The principle is to use the window opening drill bit to open holes in the casing of the oil layer, and then use the hydraulic jet action of high-pressure jets and the rotary crushing action of small drill bits to brea...

AI Technical Summary

Problems solved by technology

[0010] At present, the traditional radial well sealing structure uses a rubber seal at the joint between the oil pipe and the steering gear. When the oil pipe is pressed down, the seal between the rubber seal and the steering gear is a sliding static seal structure. Parts are prone to fatigue and wear problems, and the spikes on the injection pipe are easy to pierce the rubber, resulting in sealing failure. Because the sealing of the radial well tubing has become the main indicator of its completion degree, poor sealing will lead to leakage of high-pressure injection fluid , the hydraulic pressure is reduced, and the formation cannot be broken; moreover, fluid sealing and power feeding are a contradiction. In the existing radial horizontal well tubing sealing device, if the sealing is too tight, the tubing activity will be reduced, or even locked, and the follow-up Follow-up cannot be guaranteed

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