Sandvik Coromant 7859146 Turning Insert 35 Diamond Coroturn Tr

Product Description

The SANDVIK COROMANT 7859146 is a solid carbide turning insert designed for precision external and internal turning operations on CNC lathes and turning centers. Identified by ISO code TR-VB1312-F 4415, this insert features a 35-degree diamond shape with a neutral hand orientation and a 1.19 mm (0.0469 inch) corner radius. The CVD-applied multilayer coating — TiCN, Al2O3, and TiN — delivers strong wear resistance and thermal stability across a range of cutting conditions. The manufacturer grade 4415 positions this insert for both continuous and interrupted cuts, making it a reliable choice for production turning environments where consistent tool life and dimensional accuracy are required.

This insert is suited for turning cast iron and ferrous workpiece materials, corresponding to ISO primary material code K and secondary material code P. It is used in lathe toolholders compatible with the CoroTurn TR series, which employs a clamp-and-screw holding method. Typical applications include profile turning, shoulder turning, and finishing passes on medium to small diameter components in job shops, production facilities, and general machining operations. The 8.00 mm inscribed circle and 4.53 mm insert thickness make it appropriate for light-to-medium depth-of-cut scenarios where precise corner geometry is critical.

Key Features

• CVD multilayer coating: TiCN, Al2O3, TiN for extended wear resistance and thermal protection
• 35-degree diamond insert shape (shape code T) for high-precision profile and contour turning
• 1.19 mm corner radius provides a balance between edge strength and surface finish quality
• Neutral hand orientation for flexible toolholder compatibility
• Clamp-and-screw holding method for secure, repeatable seating in CoroTurn TR toolholders
• 5-degree relief angle suited for finishing and light roughing passes

Compatibility

Designed for use with CoroTurn TR series toolholders that accept TRVB-style inserts with a clamp-and-screw holding method. Insert size code 1312 should be matched to the appropriate toolholder designation when ordering replacement or upgrade inserts.

Installation Notes

Installation should be performed by a qualified machinist or tooling technician with the machine fully powered down and the spindle locked before changing inserts. Use the correct torque wrench and manufacturer-specified clamping hardware when seating the insert to ensure proper contact with the toolholder pocket. Inspect the toolholder pocket for chips or debris before installing the insert, as contamination can cause poor seating and premature edge failure. Never attempt to reseat or adjust the insert while the machine is running.