Bottom hole hammer reverse circulation follow pipe drill

Abstract

The present invention discloses a down-the-hole hammer reverse-circulating pipe-following drill bit. It is mainly formed from the components of casing shoe, drill bit body, slag rod, Z-shaped drill bit flapper, pin shaft and elastic pin. Said invention also provides the connection mode of all the above-mentioned components, and also provides its operation method.

Description

technical field [0001] The invention relates to a rock-soil drilling machine tool for basic engineering construction, in particular to reverse circulation follow pipe drilling. Background technique [0002] Follow pipe drilling is an effective method for drilling holes in complex formations such as broken, lost, quicksand, pebbles and gravels. The existing follow-up drilling is mainly positive circulation drilling. Most of the casing diameters are small-diameter follow-up drilling. Most of them use single eccentric drill bits and positive circulation slag discharge. They are mainly used for rock mass anchorage drilling and dam foundation observation holes. Waiting for construction. The single eccentric casing drilling tool developed by HALFAX in the UK and the HALFAX drilling tool with the inlet diameter is transmitted through the horizontal pin of the suspended drill bit, which may easily cause the deformation of the horizontal pin and cause the drill bit to be unable to c...

AI Technical Summary

Problems solved by technology

The double-rotary drilling method has the advantages of large borehole diameter and large drilling depth, advanced casing drilling, and easy casing pulling, unscrewing and unloading; the disadvantage is that it can only be applied to positive circulation drilling, and the slag discharge is not smooth. The casing boots used are expensive and are easy to stay in the hole, the diameter of the casing inserted is limited, the structure of the drilling rig is complicated, and the power consumption is large

The double eccentric tubular drill produced by Mitsubishi, a subsidiary of Ingersoll-Rand, has a large loss of effective use area of ​​the drill valve in structure, and fewer teeth on the edge, which affects the use of the drill. life, and it is only suitable for positive circulation drilling, the slag discharge efficiency is low, the joint surface of the two valves is a vertical surface, and the rock slag is easily caught between the two valves when the drill is lifted, so that the two valves cannot be accurately collected into the sleeve. The drill gets stuck inside the pipe, which brings inconvenience to lifting the drill

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