摘要 |
A programmed automatic drill control for optimizing the drilling of subterranean holes by large drilling machinery such as blast hole drills. Sensing means are provided to sense a first set of drilling parameter limits to effect maximum r.p.m. of the motor to rotate the pipe drilling bit and to sense a second set of drilling parameter limits to effect a maximum rate for the motor to drive the hoist pull-down mechanism. These conditions will prevail until a sensed limit is reached or the drilling conditions require operation along a torque or force limit set value. When a limit is reached, the control will regulate at a value of r.p.m. or rate which is consistent with maintaining operation at the limit value. In a preferred embodiment, the sensing of a first set of drilling parameters include a sensing of head position of the pipe drilling bit, the force on the drilling bit as well as vertical and horizontal vibration of a drilling pipe and the sensing of a second set of drilling parameters include sensing head position of the pipe drilling bit, the horizontal and vertical vibration of the drilling pipe, the rotary amps and speed of the motor to drive the drill pipe and the air pressure in the drill pipe.
|