The choice of rockbreakers at Sherritt's Fox Mine

CIM Bulletin, Vol. 79, No. 885, 1986

JOHN G. KELLY, Chief Mine Engineer, Sherritt Gordon Mines Limited, Fox Operations Lynn Lake, Manitoba

In 1982 an extensive study was carried out to determine the best means of size reduction for the ore to be hoisted through the borehole hoisting system at Sherritt Gordon's Fox Mine. The study examined three alternatives:1. a jaw crusher,2. pneumatic rockbreaker(s) at a grizzly, and3. hydraulic rockbreaker(s) at a grizzly. The final decision was a compromise between alternatives 2 and 3. Two rockbreakers, one pneumatic and one hydraulic, were installed over a single grizzly. Some modifications have been made to the system, but over-all it has operated at acceptable levels since its installation in July 1983. As all the ore passes through a jaw crusher before being hoisted to surface, an evaluation of the relative performance and cost-effectiveness of the jaw crusher and the two types of rockbreakers is possible. This paper outlines the initial study, and compares the three breaking systems in operation at Fox Mine.

Keywords: Underground mining, Rockbreaking system, Jaw crushers, Pneumatic rockbreakers, Hydraulic rockbreakers, Borehole hoisting system, Equipment maintenance