Tooling Systems Optimized for Steel Materials

The latest Sandvik Coromant grades enable the performance of medium-to-heavy interrupted cuts and removal of the hardened layer (cut as deep as 2 mm) in case- and induction-hardened steel components. For these applications, CB7125 and CB7135 offer longer and more consistent tool life, good levels of surface finish and consistent dimensional tolerances, according to the company.

These products are optimized for turning steel materials with a hardness ranging 58-62 HRC. Designed for medium intermittent cutting, CB7125 features a PVD coating that provides improved wear and fracture resistance for extended tool life. This grade, which contains medium CBN content, is especially useful for turning shaft splines and shafts with chamfered oil holes or pockets, the company says. Further applications include gear facing, the hard-to-soft turning of crown wheels and the removal of hardened layers.

The CB7135 grade is pitched at the efficient longitudinal turning of gears and shafts with unchamfered keyways or pockets, as well as CV joint components such as the inner/outer race and cage. Featuring a high CBN content, the grade offers high fracture resistance and predictable machining results, the company says.

Available for T-Max P, CoroTurn 107 and CoroTurn TR tooling systems, the grades come in both positive and negative basic shapes, with various edge preparations. Cutting data recommendations for CB7125 include a cutting speed ranging 100-200 m/min (328-656 ft./min) and feed rate ranging 0.05-0.45 mm/rev (0.002-0.018 in/rev), while for CB7135 a cutting speed ranging 80-160 m/min (262-525 ft./min) and feed rate ranging 0.05-0.4 mm/rev (0.002-0.016 in/rev) should be achievable, depending on the specific application.

With the introduction of these systems, the company now offers a complete hard-part turning solution, along with the existing and complementary CB7105 and CB7115 grades, which are suitable for continuous or continuous-to-light interrupted cutting operations, the company says.