PCBN Inserts Improve Feed Rates, Chip Flow
To eliminate the difficulties of hard turning operations, Seco Tools has added a grade format and several geometries to its line of PCBN (polycrystalline cubic boron nitride) inserts.
Seco Tools has added a grade format and several geometries to its line of PCBN (polycrystalline cubic boron nitride) inserts intended to reduce the difficulty of hard turning. The additions to the line broaden the CH3515 insert grade and introduce the solid CBN150 insert grade, long and short wiper geometries, and laser-etched chipbreakers.
The CH3515 insert grade is said to offer reliability in harsh cutting conditions with heavy interrupted cuts, while the CBN150 solid insert grade yields high surface finish quality during light interrupted and continuous hard turning cuts. The complete line now includes a broader range of sizes and geometries to optimize all hard turning operations. According to the company, cost per edge drops with an increased number of cutting edges per insert.
Improved hard turning feed rates and/or surface finish quality result from the product’s long WL and short WS wiper radii. The WL wiper inserts promote feed rate increases while maintaining surface finish quality. With the WS wiper, cutting forces drop by as much as 15 percent for improved machining in low-stability conditions, according to Seco.
The laser-etched chipbreakers are designed for applications that transition from hard to soft part surfaces while enabling increased depths of cut and feed rates over previous insert designs, Seco claims. The laser-generated, flowing-radii chipbreakers are said to exceed the performance of ground chipbreakers in generating smooth insert walls and reducing sharp corners. These improvements are said to produce smoother chip flow and help prevent chipping while increasing chipbreaker application range.
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