Sandvik Coromant 5781812 Turning Insert TRVB1302-F 1125

Product Description

The SANDVIK COROMANT 5781812 is a solid carbide turning insert in the CoroTurn TR series, designed for external turning operations on CNC lathes and turning centers. Grade 1125 carbide substrate features a dual-layer PVD coating of TiAlN and AlCr2O3, providing heat resistance and wear protection during interrupted and continuous cuts. The insert carries a diamond (T) shape with a 60-degree included angle, a 0.3150-inch (8 mm) inscribed circle, and a 0.0079-inch (0.20 mm) corner radius. Neutral hand orientation and screw holding make it straightforward to seat in compatible CoroTurn TR toolholders. Machinists and CNC operators install this insert in production environments where consistent edge life on steel and stainless steel is required.

This insert is intended for turning steel (ISO material code P) as its primary workpiece material and stainless steel (ISO material code M) as its secondary workpiece material. The F chip breaker geometry is suited for finishing and light roughing passes where controlled chip formation and surface finish are priorities. It is used in production turning on both horizontal and vertical turning centers, as well as manual engine lathes equipped with CoroTurn TR-compatible toolholders. The ISO code TR-VB1302-F 1125 identifies the insert within the CoroTurn TR platform for direct catalog cross-reference.

Key Features

• Grade 1125 solid carbide with PVD-applied TiAlN and AlCr2O3 dual-layer coating for elevated heat and wear resistance
• Diamond (T) insert shape with 60-degree angle and 5-degree relief angle for positive cutting geometry
• F chip breaker geometry optimized for finishing and light roughing on steel and stainless steel
• Neutral hand orientation — compatible with both right-hand and left-hand toolholder setups
• Screw-mounted insert holding method for secure, repeatable seating and quick indexing
• Two cutting edges per insert to maximize value per unit consumed

Compatibility

Designed for use in CoroTurn TR series toolholders that accept TRVB-style inserts with a 1302 insert size code. ISO code TR-VB1302-F 1125 can be used to cross-reference compatible toolholder models within the CoroTurn TR platform. No additional specific model compatibility was provided in the available product data.

Installation Notes

Insert installation and indexing should be performed by a qualified machinist or CNC tooling technician with the machine in a full stop and all axes locked out per shop lockout-tagout procedures. Use the appropriate Torx or hex key to seat the clamping screw to the toolholder manufacturer's specified torque — do not overtighten, as this can fracture the carbide substrate. Inspect the insert pocket and seating surface for chips or debris before seating a new insert. Follow the toolholder manufacturer's recommended starting cutting parameters for grade 1125 in the target workpiece material before optimizing feeds and speeds.