Princes Risborough-based Sumitomo Electric Hardmetal Ltd (
www.sumitomotool.com) has extended its range of Sumidia DA1000 high-density ultra-fine PCD turning, milling and boring inserts to include Sumida Break Master with special NLD/NGD 3-D chip-breakers for semi-finishing and fine-finishing operations.
Both Break Master chip-breaker designs incorporate a ‘3-D presentation’ for the 25deg top rake angle, with the NLD type able to achieve high orders of surface quality due to its improved chip control and sharp cutting edge.
The NGD type with a 20deg top rake is suitable for more-general machining cycles and medium-finishing cuts. The Sumidia PCD range uses a fine-sintered diamond powder (on a carbide substrate) that is suitable for non-metallic materials and non-ferrous machining.
According to the application, NLD and NGD chip-breaker insertscan be run at cutting speeds of between 100 and 3,000m/min, with feed rates around 0.15mm/rev. Depths-of-cut for NLD are between 0.1 and 0.8mm, while NGD should be between 0.5 and 2.0mm.