Sandvik Coromant 5730842 Turning Insert DCMT21.51-MM 1125

Product Description

The SANDVIK COROMANT 5730842 is a solid carbide turning insert in the DCMT style, designed for external turning operations on CNC lathes and turning centers. It carries the 1125 manufacturer grade with a PVD-applied TiAlN and AlCr2O3 dual coating, offering wear resistance and thermal stability during continuous and interrupted cuts. The insert features a 55-degree diamond shape, a neutral hand orientation, and an MM chip breaker geometry. With a 1/4-inch inscribed circle and a 1/64-inch corner radius, this insert is suited for finishing and semi-finishing passes requiring tight tolerances and controlled chip formation. It is installed by licensed machinists and CNC tool-setters.

This insert is engineered primarily for steel workpieces and is also rated for stainless steel, superalloys, and titanium applications, placing it in ISO material groups P, M, and S. It fits standard DCMT screw-lock toolholders using the CoroTurn 107 series system. Typical applications include shaft turning, facing, and profiling on both light-duty and production-volume turning setups. The 2-cutting-edge configuration allows the insert to be indexed once before replacement, supporting cost-effective tooling management in high-throughput environments.

Key Features

• 1125 grade carbide with PVD TiAlN and AlCr2O3 dual coating for extended tool life in steel and stainless cutting
• 55-degree diamond insert shape (Shape Code D) for versatile turning and profiling access
• MM chip breaker geometry optimized for controlled chip evacuation during finishing cuts
• Neutral hand orientation compatible with standard right-hand and left-hand DCMT screw-lock holders
• 2 cutting edges per insert for indexable service life
• CoroTurn 107 series compatibility for consistent clamping and repeatability

Compatibility

Designed for use with DCMT-style screw-lock toolholders in the CoroTurn 107 series. ISO code DCMT 07 02 04-MM 1125 can be used to cross-reference compatible holder systems. Rated for primary use on steel (ISO P) and secondary use on stainless steel, superalloys, and titanium (ISO M, P, S).

Installation Notes

Installation is performed by a qualified machinist or CNC setup technician. Power down and lock out the machine spindle before indexing or replacing any cutting insert. Use the appropriate Torx or hex key to seat the clamping screw to toolholder specification — do not over-torque the insert screw, as carbide inserts are brittle and will crack under excessive clamping force. Inspect the insert pocket and seating surface for chips or debris before seating the new insert.