Pressure resistant tool for reducing frictional resistance of horizontal well section

Abstract

The invention relates to a pressure resistant tool for reducing frictional resistance of a horizontal well section, which is used for reducing the frictional resistance of the horizontal well section and improving horizontal section extending and drilling capacity. The technical scheme includes: the pressure resistant tool for reducing the frictional resistance of a whole well consists of a pulse part and a vibration part. The pulse part mainly comprises an upper joint, a power part, an upper abrasion-resistant block, an upper fixing sleeve, a lower abrasion-resistant block, a lower fixing sleeve, a lower valve and a lower joint. The vibration part mainly comprises a spline transmission shaft, a spline righting tube, a locking nut, a disk spring, a supporting shell, a piston rod, a piston bush, a piston nut and a pulse pup joint. The vibration part is in threaded connection with the upper end of the pulse part. The overall overflowing area of a valve part driven by a motor rotor is gradually reduced, and fluid energy is converted into a series of pulse pressure to be transmitted to the vibration part. The pressure resistant tool has the advantages of high axial vibration capacity and simple structure, the frictional resistance between a drill stem and the well wall can be reduced, and the horizontal well and large-displacement well horizontal section extending and drilling capacity is improved.

Description

technical field [0001] The invention relates to an anti-back pressure tool for reducing the frictional resistance of a horizontal well section and improving the extended drilling ability of the horizontal section in the drilling of directional wells, horizontal wells and extended-reach wells. Background technique [0002] With the deepening of the exploration and development process, the proportion of directional wells, horizontal wells and extended reach wells is increasing. Long horizontal section drilling technology has been widely used at home and abroad, mainly due to its good input-output ratio. At present, the drilling cost of horizontal wells in foreign countries has been reduced to 1.2 to 2 times that of vertical wells, while the output is 4 to 8 times that of vertical wells. As a potential new technology, horizontal well technology mainly has the following advantages: restoring the productivity of old wells, developing complex types of oil and gas reservoirs, faci...

AI Technical Summary

Problems solved by technology

Since the 1990s, more than 7,000 wells have been drilled with coiled tubing in the world, with an increase of 750-850 wells per year. As the length of the flat well section increases, the friction between the coiled tubing and the wellbore wall increases. Due to the small size of the coiled tubing, its high flexibility, and poor ability to transmit drilling pressure, the drilling footage of the horizontal section is limited, and it only relies on the horizontal drive generated by the ground injection head. Coiled tubing is often unable to reach the expected depth, and the difficulty of running coiled tubing in horizontal well sections has also become one of the main factors restricting its development.

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