The Advantages of Inhole Motor Drilling.
Kravits SJ; Stainato A; Finfinger GL
Coal Min 1984 Nov; 21(11):44-46
The Bureau of Mines pioneered the rotary drilling technology of horizontal boreholes into coal as an effective method of removing methane from coalbeds. To date, more than 10 billion cu ft of methane has been removed, consistently reducing methane emissions at active faces by at least 50%. Although horizontal boreholes have been drilled to depths greater than 2,500 ft, inherent problems have prevented universal acceptance of this technique. This paper presents a discussion on the advantages of inhole motor drilling compared with rotary drilling.
Coal Min., V. 21, No. 11, Nov. 12, 1984, PP. 44-46