Drilling Technology of Over-thick Overburden Layer Drilling in Pre-detecting Hole in Henan

Abstract:

A drill sticking accident caused ZK001 borehole abandonment in Jiaozhuang iron ore area of Henan, the construction technology was improved by using proper equipment and high-quality mud, the final hole with depth of 1115.72m was reached with good technical indexes. Analysis is made on the borehole structure, drilling methods and properties of flushing fluid; the problems appeared in the construction and the countermeasures are briefly discussed.