The 6 row cutter, with even kerf spacing throughout, has set a new record for life in Sabinas Mine, one of the hardest mines in Mexico. The Unconfined Compressive Strength (UCS) of the rock at this mine ranges from 36,000 psi (248 MPa) to 40,000 psi (276 MPa) and there have been a number of tests from various competitors over the years.
For this test with the 6 row cutters, the raises were completed using a 73R with standard strength 11-1/4” pipe on an 8 ft. diameter reamer operated by the number one Raiseboring contractor in Mexico. The results of the test are shown below:
The 6 row cutter fits into the same saddle as the standard Magnum cutters. The same cutter is used throughout, which eliminates the possibility of dressing the head incorrectly and reduces the number of different types of cutters that need to be stocked in inventory. The cutter outperforms the standard product in select ground where there is a high UCS but the tensile strength of the rock may be lower than normal. There is also a benefit from two cutters in a row follows the exact same path, stressing the rock twice per reamer revolution. The MKC6 cutter is otherwise a Magnum cutter with the same journal, bearings and other components. A version of the Magnum 6 row cutter also exists that fits the Magnum V saddle (that cutter is shown below), the MVK6 cutter.