TURNING INSERT - NEGATIVE_DNMG

Insert designation (ISO 1832)

• D: rhombic shape, 55° included angle
• N: 0° clearance angle (negative insert)
• M: tolerance class M
• G: cylindrical fixing hole with chipbreakers on both faces
• 11: cutting edge length 11.6 mm
• 04: thickness 4.76 mm
• 02: corner radius 0.2 mm
• E: rounded cutting edge
• FF: Pramet chipbreaker for fine finishing
• T8315: Pramet PVD-coated carbide grade

Usage notes

• Work within the depth of cut range of 0.2–1.5 mm. The FF geometry is intended for finishing, not roughing.
• Keep the feed light relative to the 0.2 mm corner radius to protect the cutting corner and achieve the required surface finish.
• Clamp in negative toolholders and boring bars for size 11 DN.. inserts (for example DDJN, PDJN, PDNN, PDXN and PDUN types). Make sure the insert seat and shim are clean before clamping.
• Index to a fresh edge before wear becomes excessive, and use all 4 cutting edges before discarding the insert.
• Turning stainless steel produces hot, sharp chips. Use eye protection and machine guarding.

The DNMG 110402E-FF:T8315 from DORMER PRAMET is an ISO negative turning insert of the DNMG family. It has a 55° rhombic (D-shape) form, 0° clearance (N), tolerance class M, and a fixing hole with chipbreakers on both faces (G), which gives 4 usable cutting edges per insert.

The FF chipbreaker is a strongly positive geometry for fine finishing in continuous to lightly interrupted cuts, with rounded cutting edges. Together with the small 0.2 mm corner radius, it suits low depths of cut and light feeds where good chip control and surface finish are required.

T8315 is a highly abrasion-resistant grade of the Pramet T8300 series. It combines a sub-micron WC-Co substrate with relatively low cobalt content and a nano-layered PVD coating with gradient transitions. The grade reduces notch wear on the main cutting edge and allows higher cutting speeds when machining stainless steels.

Key features

• Double-sided negative insert with 4 cutting edges for economical use
• 55° rhombic shape suited to profiling and finishing of contours
• FF fine-finishing chipbreaker with rounded cutting edges
• T8315 PVD-coated fine-grained carbide, ISO M05–M20
• Depth of cut range 0.2–1.5 mm

Applications

Finishing and fine finishing of stainless steels (ISO M) on CNC lathes, using negative toolholders and boring bars for DN.. style inserts.

Manufacturer EDP number: 6753601

Flat 55° rhombic (diamond-shaped) insert, usable on both sides, with a central cylindrical fixing hole and chipbreaker grooves on both the top and bottom faces.

• Inscribed circle (IC): 9.525 mm, the circle tangent to every side of the insert
• Cutting edge length (L): 11.6 mm, the length of each side
• Thickness (S): 4.76 mm
• Corner radius (RE): 0.2 mm
• Fixing hole diameter (D1): 3.81 mm
• Side faces perpendicular to the top and bottom faces (N, 0° clearance)

How to choose the right DNMG insert

Select the chipbreaker and grade according to the operation and the workpiece material:

• Stainless steel, fine finishing at small depths of cut: FF chipbreaker in T8315 (this product).
• Stainless steel, fine to medium machining: NF or SF chipbreakers in T8315, which cover a larger depth of cut range.
• Stainless steel, fine to heavy machining: NM chipbreaker in T8315.
• Corner radius: 0.2 mm keeps cutting forces low and suits small contour radii. 0.4 mm or 0.8 mm gives a stronger corner and allows higher feeds.
• Other materials: T8315 is optimised for ISO M (stainless steel). For general steels (ISO P), choose a grade intended for steel.

The DNMG-FF family also includes sizes 110402, 110404 and 110408 (IC 9.525 mm) as well as 150404, 150604 and 150608 (IC 12.7 mm).