Sandvik Coromant 7861074 Turning Insert VBMT333-PM 4425

Product Description

The SANDVIK COROMANT 7861074 is a VBMT333-PM solid carbide turning insert from the CoroTurn 107 series, designed for precision external turning operations on CNC lathes and turning centers. It features a 35-degree diamond insert shape with a 3/8 inch inscribed circle and a 1.19 mm (0.0469 inch) corner radius. The insert is CVD-coated with an Al2O3, TiN, and TiCN multilayer system in manufacturer grade 4425, which provides wear resistance and thermal stability during interrupted and continuous cuts. Two cutting edges and a PM chip breaker geometry support productive metal removal in demanding production environments. Licensed machinists, CNC operators, and toolroom technicians are the primary installers of this insert.

This insert is engineered primarily for machining steel and cast iron workpieces, covering ISO material groups P and K. The PM chip breaker geometry is well suited for medium to finishing cuts where chip control and surface finish consistency are priorities. It fits into VBMT-style insert pockets on compatible CoroTurn 107 toolholders and is held in place by a clamp or screw mounting method. Typical applications include shaft turning, facing, and profiling operations in general machining and production shops working with carbon steels, alloy steels, and grey or nodular cast iron.

Key Features

• CVD-applied Al2O3, TiN, and TiCN multilayer coating in grade 4425 for extended tool life on steel and cast iron
• 35-degree diamond insert shape (V) with neutral hand orientation for versatile toolholder pairing
• PM chip breaker geometry engineered for medium to finishing cuts with reliable chip control
• 1.19 mm corner radius balances surface finish quality with edge strength
• Two cutting edges per insert, reducing per-edge tooling cost in high-volume turning
• Clamp and screw holding method provides secure seating under interrupted cut conditions

Compatibility

Designed for use with VBMT-style CoroTurn 107 toolholders that accept a 3/8 inch inscribed circle insert with a 0.1732 inch hole diameter. ISO code VBMT 16 04 12-PM 4425 can be used to cross-reference compatible toolholder pockets in standard turning tool catalogs. Primary workpiece materials are steel (ISO P) and cast iron (ISO K).

Installation Notes

Insert installation and indexing should be performed by a qualified machinist or CNC toolroom technician with the machine in a locked-out, zero-energy state before any toolholder is accessed. Seat the insert firmly into the pocket and tighten the clamping screw to the toolholder manufacturer's specified torque using a calibrated torque driver — do not overtighten or use substitute fasteners. Inspect the insert pocket for debris, damage, or wear before seating a new edge. Always verify runout and tool offset data in the CNC control after any insert change before resuming a cutting program.