LNMU, ONMU, and PNMU are Tungaloy's double-sided milling insert families with different shapes and edge counts:

• LNMU — square shape, 8 cutting edges per insert. The most versatile geometry, used for high-feed milling and general face milling.
• ONMU — octagonal shape, 16 cutting edges per insert. Maximum economy for face milling at shallow depths of cut.
• PNMU — pentagonal shape, 10 cutting edges per insert. Combines large depth-of-cut capability with high edge count.

All three accept PVD-grade coatings (AH725, AH3135, AH120, AH130) and fit Tungaloy's standardized cutter body seats.

Both are PVD-coated grades for stainless and high-temperature alloys, but with different compositions. AH725 uses an Al-rich TiAlN coating optimized for general stainless steel and steel milling — the most versatile PVD grade. AH3135 uses a TiSiN (titanium-silicon nitride) coating with superior heat resistance — ideal for high-temperature alloys (Inconel, Hastelloy, titanium) and interrupted cuts where temperatures exceed 800°C.

A double-sided insert has cutting edges on both top and bottom faces, doubling the number of usable edges per insert (8-16 edges vs 4 for single-sided). The benefits are:

• Lower cost-per-edge — 40-50% reduction vs single-sided inserts
• Better insert rigidity — thicker cross-section handles higher cutting forces
• Higher MRR — combined with high-feed geometries, achieves 3-5× the material removal rate

Drawbacks: requires more precise cutter bodies (tolerance on insert seat) and slightly more complex indexing (need to flip the insert, not just rotate).

Milling and turning inserts have fundamentally different geometries and chip-breaker designs. Turning inserts have a single continuous cutting edge optimized for continuous chip flow at varying depths-of-cut. Milling inserts have multiple cutting edges that engage and disengage the workpiece as the cutter rotates, requiring:

• Stronger cutting edges (higher impact resistance)
• Different chip-breaker geometries optimized for varying chip thickness
• Higher wear resistance (cutting edge is in/out of cut repeatedly)
• Higher-toughness grades (impact loads during entry/exit)

Always use milling-grade inserts for milling operations, not turning-grade inserts.

Yes — every insert in this catalog is 100% genuine Tungaloy from Iwate, Japan (part of the IMC Group). All SKUs are sourced directly through authorized distribution channels and include the original Tungaloy packaging and grade markings. Beware of counterfeit Tungaloy inserts sold at suspiciously low prices on marketplaces; these are typically substandard Chinese carbide with copied geometry and inconsistent quality.

Tungaloy milling inserts fit the following Tungaloy cutter body families:

• DOCTL — for LNMU ZER high-feed milling
• EPCTL / EPCT — for LNMU / LMMU face milling
• ENEQ — for ONMU octagonal face milling
• PNEQ — for PNMU pentagonal face milling
• TungForce-Rec — for TOMT shoulder milling
• DOFR — for XPMT high-feed milling

Many inserts also fit competitor cutter bodies through standardized insert seats (e.g., LNMU 0303 fits Sandvik R200-11 series). Browse our milling cutter catalog for compatible bodies or contact us for cutter body recommendations.