Unconsolidated formation coring device and method

Abstract

The embodiment of the invention provides an unconsolidated formation coring device and method. The device comprises a slurry injection assembly, a drilling assembly and a lifting assembly, wherein thedrilling assembly comprises a drilling machine, a drill rod, a reducing joint, a core barrel, a drill bit joint and a drill bit; the drill rod, the reducing joint and the core barrel are of hollow structures; the reducing joint is used for communicating the lower end of the drill rod with the upper end of the core barrel; the inner diameter of the reducing joint is smaller than that of the drillrod; the drill bit joint is of a wedge-shaped structure and arranged at the lower end of the inner wall of the core barrel; the slurry injection assembly comprises a slurry injection pipeline, a sandthrowing opening, a pressure storage tank and a slurry pump; the sand throwing opening is used for throwing river sand into the slurry injection pipeline, so that the river sand can be filled into anannular gap between the drill bit joint and the rock core entering the core barrel; and the lifting assembly is used for lifting the drilling assembly. According to the unconsolidated formation coringdevice and method in the embodiment, the river sand is thrown through the sand throwing opening, the gap between the drill bit connector and the rock core is filled with the river sand, and the rockcore obtaining rate can be increased.

Description

technical field [0001] The invention relates to the technical field of geological exploration, in particular to a loose formation coring device and method. Background technique [0002] In geological exploration and construction, when coring or sampling loose formations, conventional coring and rope coring are commonly used at present, and single-tube or double-tube coring tools are used. [0003] For loose formations, the cost of existing coring tools is high and the coring operation is complicated. For loose formations, the coring effect is poor, the core recovery rate is low, and core loss is easily caused. Moreover, during drilling with single-tube or double-tube coring tools, mud is required to protect the hole wall, remove rock powder, cool the drill bit, lubricate the drill tool, etc., and the mud directly passes through the core, which has a greater erosion effect on the core, so Cores are susceptible to contamination, making it difficult to maintain structural inte...

AI Technical Summary

Problems solved by technology

[0004] The embodiment of the present invention provides a loose formation coring device and method, which is used to solve the defect of poor coring effect in the loose formation in the prior art, and realize the goal of Better results in loose ground coring

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