Walter 6364140 Turning Insert CPGT21.51-MK4 WKK20S Carbide

Product Description

The WALTER 6364140 is a solid carbide turning insert in the CPGT21.51-MK4 configuration, coated with a multilayer CVD TiCN/Al2O3/TiCN finish under the Tiger-tec Silver WKK20S grade designation. It features an 80-degree diamond insert shape, a 1/4-inch inscribed circle, and a 1/64-inch corner radius. The positive rake geometry and honed cutting edge style support precise material removal in demanding turning, facing, and boring operations. This insert is designed for use by machinists and tooling professionals working with CNC lathes and turning centers in production environments.

This insert is primarily suited for machining cast iron and is secondarily rated for steel. The MK4 chip breaker geometry is optimized for finishing and light semi-finish cuts in these material groups, corresponding to ISO material grades K20 and P10. Typical applications include turning, facing, and boring operations where consistent chip control and surface finish are required. The neutral hand orientation makes it adaptable across a range of toolholder setups.

Key Features

• CVD multilayer coating: TiCN/Al2O3/TiCN for wear resistance in cast iron and steel machining
• 80-degree diamond insert shape with 1/64-inch corner radius for versatile profiling and straight turning
• Positive rake angle of 7 degrees reduces cutting forces and supports lighter cuts
• MK4 chip breaker geometry provides controlled chip formation in finishing applications
• Screw-held insert with 0.11-inch hole diameter for secure toolholder mounting
• 2 usable cutting edges per insert
• Compatible with turning, facing, and boring operations - multi-use rated

Compatibility

Designed for use in CPGT-style screw-on toolholders accepting a 1/4-inch inscribed circle diamond insert. ISO code CPGT060204-MK4 WKK20S; industry standard number CPGT2(1.5)1-MK4 WKK20S. Conforms to ANSI and ISO insert standards.

Installation Notes

Installation is performed by qualified machinists or tooling technicians using the appropriate screw-clamp toolholder for CPGT-style inserts. Ensure the machine spindle is fully stopped and the toolholder is secured in the turret before seating or replacing the insert. Use the correct torx or hex key to tighten the insert screw to the toolholder manufacturer's specified torque. Inspect the insert pocket and seating surface for chips or debris before mounting to ensure proper insert stability and edge geometry.