Effective chip evacuation has always been one of the main problems with heavy grooving, where there is a constant risk of chip jamming which can result in loss of tolerance or tool breakage in some instances. The development of -GM geometry makes it possible to groove deeply in a continuous in-feed operation to achieve high metal removal rates without risk of damage to the tool or the component surface. Additional benefits include easier programming when stopping or backing-out as chip removal is no longer needed. Also, the positive edge of -GM geometry makes the insert cut lightly and smoothly to generate low cutting forces, thereby reducing vibration and requiring less machine power.
As with all grooving operations it is preferable to aim coolant directly into the groove as this will further aid chip evacuation. A toolholder or cutting head featuring integrated coolant delivery capabilities is recommended, while for grooving ductile or stringy materials, high pressure coolant will provide a definite advantage.
The CoroCut® R size inserts with -GM geometry for heavy grooving are available in 12, 12.7 and 15 mm widths, and are applicable in a large range of tooling solutions, including CoroTurn® SL70.
With a recommended feed rate range of 0.15-0.5 mm/rev, first choice grades include: GC1125 for ISO-P and ISO-N materials; GC1125 for ISO-M; GC4225 for ISO K; and GC1105 for ISO-S.