Optimization Design of Self-propelled Hydraulic Jet Bit for Coalbed Methane

Jun Sun

《International Core Journal of Engineering》 6卷3期 (2020/03) Pp. 46-52

https://doi.org/10.6919/ICJE.202003_6(3).0010

摘要

A self-propelled hydraulic jet bit is designed according to the characteristics of small shaft diameter and small turning radius in the technology of cased radial horizontal well of coalbed methane. The flow control equation of nozzle jet flow field is established, which is discretized by the finite volume method. The equations are solved by combining the realizable K - ε model, and the influence of jet bit parameters on drilling effect is studied. By optimizing the parameters of the jet bit, it is concluded that when the diameter of the locating circle of the jet bit's forward nozzle is 7mm, the diameter of the forward and reverse nozzles is 1.3mm, 0.8mm or 1.1mm, 0.9mm, and the angle between the axis of the forward and reverse nozzles and the axis of the hydraulic jet bit is 30 ° and 60 °, the jet bit can break 40 mm holes and provide more than 1500 N self driving force.

關鍵字

Self advancing ； Water jet ； Rock breaking ； Jet bit

參考文獻

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