Seco 02959957 Turning Insert DNMU332-M3 TP2501 Diamond 55

Product Description

The SECO 02959957 is a solid carbide turning insert in the DNMU-M3 series, designed for precision metal cutting in CNC turning applications. It features a 55-degree diamond shape (DNMU style) with a neutral hand orientation and four usable cutting edges. The insert carries a CVD-applied Duratomic multilayer coating consisting of TiCN, Al2O3, and Cr, achieving manufacturer grade TP2501. With an inscribed circle of 0.375 inches, a corner radius of 0.0315 inches, and an insert thickness of 0.1874 inches, this insert is built for reliable stock removal across a range of ferrous workpiece materials. It is installed using clamp, pin, or lever-lock holding methods.

This insert is suited for steel, stainless steel, and cast iron machining in both roughing and semi-finishing operations. The M3 chip breaker geometry supports turning, facing, boring, and back turning on CNC lathes and turning centers in production environments. Material grades P10, P20, P30, and P35 make it appropriate for a wide band of steel and stainless applications. The Chamfered and Honed cutting edge style provides a controlled edge condition that reduces micro-chipping under interrupted or continuous cut conditions. It is sold individually but must be ordered in multiples of 10.

Key Features

• 55-degree diamond insert shape (shape code D) with negative rake for increased edge strength
• CVD Duratomic multilayer coating: TiCN, Al2O3, and Cr for wear and crater resistance
• Four cutting edges per insert, multi-tipped for maximum economy
• M3 chip breaker supports turning, facing, boring, and back turning operations
• Compatible with clamp, pin, and lever-lock toolholding systems
• Chamfered and Honed cutting edge style for improved edge stability
• Conforms to ANSI and ISO standards; ISO code DNMU110408-M3

Compatibility

Designed for use in DNMU-series toolholders that accept a 55-degree diamond insert with a 0.375-inch inscribed circle, neutral hand, clamp, pin, or lever-lock holding, and a clearance code of N. Confirmed compatible workpiece materials include steel, stainless steel, and cast iron.

Installation Notes

Installation is performed by a qualified machinist or tooling technician. Ensure the machine spindle is fully stopped and the turret is indexed to a safe position before seating or replacing inserts. Use the appropriate torque driver for the selected clamping method — clamp, pin, or lever-lock — per the toolholder manufacturer specification. Verify insert seating and edge orientation before resuming cuts.