Hollow impact drill

Abstract

The invention relates to a hollow impact drill, and belongs to the field of civil engineering and bridge pile foundation construction. The hollow impact drill comprises a gravity cylinder, a plurality of gravity plates and a plurality of annular gravity rings of different diameters, the gravity cylinder is located in the center of the hollow impact drill, and the circular gravity rings and the gravity cylinder are coaxially arranged; the annular gravity rings of the different diameters are arranged stepwise in the length direction of the gravity cylinder from small to large, and gaps exist between the every adjacent two annular gravity rings, and a plurality of hammer teeth are arranged on the working faces of the annular gravity rings. The working faces are in contact with the ground when the hollow impact drill works; the gravity cylinder and the annular gravity rings are fixed by the gravity plates, and the gravity plates are evenly distributed on the periphery of the gravity cylinder. According to the hollow impact drill, the one-time hole forming effect is enabled to be better in the piling process, the probability of the hole shifting is reduced, and the piling efficiency is improved.

Description

technical field [0001] The invention relates to the field of civil engineering and bridge pile foundation construction, in particular to a hollow impact drill. Background technique [0002] When the current bridge foundation construction needs to adopt the percussion drill bit to carry out operation, usually adopt the conventional cross-shaped (quincunx) percussion drill bit; Finally, it is the purpose to form a uniform circular hole. During the operation, the cross-shaped percussion drill mainly relies on the twisting of the lifting wire rope during the lifting of the percussion drill to drive the drill to rotate, so as to realize the impact at different positions in the circumferential direction, and finally form a circular hole. [0003] However, in the actual use of the cross-shaped impact drill bit, the landing positions of the hammer teeth in the four directions of the drill bit are random rather than uniformly distributed in the circumferential direction, which leads ...

AI Technical Summary

Problems solved by technology

[0003] However, in the actual use of the cross-shaped impact drill bit, the landing positions of the hammer teeth in the four directions of the drill bit are random rather than uniformly distributed in the circumferential direction, which leads to the formation of cross-shaped pile holes or eccentric holes in the piling. or oval hole

This requires subsequent additional use of other drill bits or other measures to correct the pile holes to make them into circular holes, which virtually increases the amount of work and increases the economic cost and time cost.

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