A new approach to 7/8-in. tapered drilling equipment at Madawaska

CIM Bulletin, Vol. 75, No. 847, 1982

R.M. GIEGERICH, Mine Superintendent, Madawaska Mines Limited, Bancroft, Ontario

This paper begins with a brief history of Madawaska Mines, a brief description of the geology, mining methods and equipment, and the historical development of 7/8-in. tapered drilling equipment. It then outlines the performance characteristics and inherent problems of the traditional 12-degree, tapered-connection, blade-type insert bits. Service-free (Unipass) button-type insert bits are presented as a possible solution to these problems. The paper concludes with an analysis of button bit performance to date.
Keywords: Underground Mining, Equipment, Maintenance, Drilling, Madawaska Mines, Bits, Button bits, Insert bits.