Application of sliding-block reverse-circulation drilling bit in multi-layer goaf detection

摘要

This paper researches specialized reverse-circulation drilling bit for multi-layer goaf detection based on the multilayer goaf detection project of iron ore mine in Yuan Village and designs a sliding-block reverse-circulation drilling bit with innovation, which is designed with large-through hole central channel, double-row inner orifice and sliding block. The structure of sliding block is used on reverse-circulation drilling bit for the first time. The performance of sliding- block reverse-circulation drilling bit is observed in practical drilling test, indicating good effect of reverse circulation, and high drilling efficiency, with the average drilling efficiency of 33.75m/h on extremely cracked land and 10.17m/h on hard land. The sliding-block reverse- circulation drilling bit can effectively solve the problem of blocking central channel since the structure of sliding block can meet the requirement on drilling. The top plate of multilayer goaf can be drilled through successfully. C-ALS three- dimensional laser scanner can be put down through the central channel to solve the difficulty of simultaneous scan and detection on multi-layer goaf.