摘要
Cutting drilling pipe and the assembly with eccentric cutting knife are usually applied in the large diameter engineering borehole construction;and in geological drilling, eccentric cutting knife can used to cut the casing pipe or coring barrel.The paper described a successful treatment practice of complex borehole accident in a drilling construction in Guizhou Province, the drilling pipe was cut down from the outside with eccentric cutting knife, and introduced the technical measures and the attentions.