Bush bulging shell type self-drilling hollow anchor rod

Abstract

The invention relates to a casing pipe rising shell type self-drilling hollow anchor bar, belonging to project supporting field, which comprises a one-off drill bit, a steel plug, a rising shell, a casing pipe, a hollow bar body, a tray and a nut. The one-off drill bit is connected at the most front end of the hollow bar body, the life design is to drill a hole; the steel plug is scyewed joint and welded together with the hollow bar body, the lower end of the steel plug is in turn hollow housed the rising shell and the casing pipe; four slots are opened on the upper of the rising shell, and tilted teeth are machined in outside; the casing pipe is held on the lower end of the tray and is fixed by the nut. The invention is applied to the supporting of coal mine back, at first the quick load-bearing requirement is reached by mechanical rising shell ahead anchoring, then the whole length anchoring is realized by injecting sand-cement slurry. The invention has convenient drilling and mounting in the construction and changes construction process of the traditional anchor bar, and realizes integration of the drilling and anchoring of the coal drift supporting and is help to safe and quick supporting of the coal drift.

Description

technical field [0001] The invention belongs to the field of geotechnical engineering anchoring support. The invention relates to a casing expansion type self-drilling hollow bolt, which is suitable for the advance support and permanent support of the roof of coal mine roadway. Background technique [0002] As an effective roadway support method, bolt support can significantly improve the stability of the surrounding rock due to its strengthening effect on the strength of the roadway surrounding rock. The economic benefit of the mine has thus become a main support form of mine roadways in all countries in the world, and represents the main development direction of coal mine roadway support technology. [0003] As early as the 1940s, the United States and the former Soviet Union had used bolt support in underground roadways. my country has used bolt support in coal mine rock roadways since 1956. Over the past few decades, the world's bolt support has experienced the followi...

AI Technical Summary

Problems solved by technology

On the other hand, the anchoring position of the end of the anchor rod cannot be determined after the resin coil is stirred, and the expected anchoring effect cannot be achieved; and the anchoring force of the resin anchoring agent will be significantly reduced after encountering water

[0005] Although a self-drilling grouting anchor is widely used in railways, highway tunnels and slope treatment, due to the complexity of coal mine rock formations, this anchor cannot be used in coal roadway support

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