Screw drill

Abstract

The invention provides a screw drill belonging to the field of drilling tools. The screw drill comprises a motor assembly, an upper shell and a lower shell, wherein the upper shell and the lower shell form a transmission chamber; the transmission chamber is internally provided with a transmission shaft and a strainer; through holes allowing drilling fluid to flow are formed in the transmission shaft; the bottom of the strainer is fixedly connected with an upper dynamic sliding bearing; the top of the inner wall of the lower shell is provided with an upper static sliding bearing; the bottom of the outer wall of the transmission shaft is sleeved by a lower dynamic sliding bearing; the bottom of the inner wall of the lower shell is in threaded connection with a lower static sliding bearing; a buffering disc spring group composed of a plurality of disc springs is arranged between the lower dynamic sliding bearing and the upper dynamic sliding bearing; and the transmission shaft is sleeved by the buffering disc spring group. By using the screw drill, the effective working time of a bit can be effectively prolonged, the drilling efficiency of the bit can be effectively increased, the bit pressure acting distance can be effectively increased, and the effective drilling depth of the bit at the one-time bit feeding pressure is can be increased.

Description

technical field [0001] The present invention relates to the field of drilling tools, in particular to screw drilling tools. Background technique [0002] The currently commonly used screw drilling tool is a downhole power drilling tool driven by the hydraulic energy of the drilling fluid. It has the function of increasing the rotation speed of the drill bit and thus improving the drilling efficiency. It also has the function of drilling directional, horizontal and other deviated sections The function, and its manufacturing and use cost is low, safety and reliability are high, and it has been widely used for many years. [0003] In the current drilling process, the main way to control the drilling of the drill bit to the bottom of the well is to manually control the intermittent drilling, and the axial direction of various drilling tools in the drill string, including the screw drilling tool, is rigid. The drill bit is always in the intermittent drilling mode during the actu...

AI Technical Summary

Problems solved by technology

[0003] In the current drilling process, the main way to control the drilling of the drill bit to the bottom of the well is to manually control the intermittent drilling, and the axial direction of various drilling tools in the drill string, including the screw drilling tool, is rigid. The drill bit is always in the intermittent drilling mode during the actual drilling process, and the continuous drilling distance of the drill bit is very short after each drill delivery, and the high-frequency drill delivery also brings continuous impact damage to the drill bit, although The screw drilling tool improves the drilling speed by increasing the drill bit speed, but it increases the impact force on the drill bit when sending the drill, and thus increases the fluctuation range of the output power performance of the screw drill tool, which shortens the working life of the drill bit. Reduced work efficiency

[0004] Therefore present screw drilling tools generally have the following defects: there is no pressure-on-bit extension function, which cannot solve the problem that the continuous drilling depth of the drill bit is shallow, and the working efficiency of the drill tool and the drill bit is low; Continuous impact between layers, short life of drill bits and drilling tools; unreasonable structure of drive shaft assembly

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