Single-action double-pipe coring overburden drill tool for air down-the-hole hammer

Abstract

The invention relates to a single-action double-pipe coring overburden drill tool for an air down-the-hole hammer. The single-action double-pipe coring overburden drill tool comprises a central coring drill tool and an overburden drill tool. The central coring drill tool is a single-action double-pipe coring drill tool and comprises a single-action vibration reduction mechanism, an inner pipe adjusting mechanism and a coring mechanism with a bayonet device; the single-action vibration reduction mechanism comprises an impact connector, a disc spring, a bearing block, a connecting shaft, a thrust ball bearing and a radial ball bearing; the inner pipe adjusting mechanism comprises a connecting shaft, a core pipe connector, an inner pipe and a nut; the coring mechanism with the bayonet device comprises an outer pipe, an inner pipe, a connecting shaft, a core pipe connector, a coring drill bit, a rolling needle, a pawl spring seat and a pawl spring; the overburden drill tool comprises a casing, a casing connector, a casing shoe, a clamp ring and a casing drill bit. The single-action double-pipe coring overburden drill tool for the air down-the-hole hammer is applicable to relevant fields such as geological mineral exploration and engineering geological survey for complex formation with loose sand, cobbles, gravel, fracture, breakage and the like.

Description

Technical field [0001] The invention relates to an air down-the-hole hammer single-acting double-tube coring and tube drilling tool, which is suitable for use in engineering geological surveys of complex formations such as loose sand, gravel and fractures, as well as geological and mineral exploration and other related fields. DTH hammer single-action double-tube coring and tube drilling tool. technical background [0002] Coring (or sampling) drilling in complex formations such as loose sand, gravel and fractures has always been a problem in the field of drilling, characterized by easy collapse of the borehole, low sampling rate, and low drilling efficiency. Through research and practical exploration, drilling technology has been greatly improved, and the wall protection effect, coring quality and core adoption rate have been significantly improved. However, for complex formations such as loose sand, gravel and fractures, the problem of formation collapse still affects drilling ...

AI Technical Summary

Problems solved by technology

[0002] Coring (or sampling) drilling in complex formations such as loose sand, pebbles, gravel and fractures has always been a difficult problem in the field of drilling. It is characterized by easy collapse of boreholes, low sampling rate, and low drilling efficiency

Through research and practical exploration, drilling technology has made great progress, and the effect of wall protection, coring quality and core recovery rate have been significantly improved. However, for complex formations such as loose sand, pebbles, gravel and fractures, formation collapse still affects drilling efficiency. , the quality of coring still cannot meet the requirements, which directly affects the accurate evaluation of strata and mine beds, and even leads to the scrapping of boreholes

For example, the natural gas hydrate deep-water shallow hole pressure-holding and heat-preservation coring tool disclosed in Chinese invention patent application No. Type core drilling tools and the controllable split-flow core drilling tools disclosed in Chinese utility model patent 89220229.7, due to the use of liquid flushing fluid, it is easy to cause sliding wave activities; there are also some other advanced down-the-hole hammer and pipe drilling tools, Good rock breaking effect and high drilling efficiency, but does not have coring function

The Chinese Invention Patent Application No. 200510021979.1 has the impact rotary method to break rocks, has high drilling efficiency, and has the effect of synchronously following the pipe while drilling. Core drilling tools hinder the improvement of core quality and recovery rate. The diameter of the through hole connecting the casing bit and the core bit is small. The gap between the coring bit and the casing bit is small. Inconvenience affects drilling efficiency

Images