null CCMT120408N-SU AC820P Wendeplatten - Sumitomo

Take advantage of the large positive geometry and the AC820P CVD coating to achieve low cutting forces and consistent finishing results; combine reliable fracture resistance with two usable cutting edges for efficient production flow. Order the insert directly via Metav Werkzeuge or consult our specialists for application advice.

Sumitomo CCMT120408N-SU AC820P indexable turning insert – large positive C‑Rhombus 80°, CVD-coated

The Sumitomo CCMT120408N-SU AC820P is a large, positive 80° C‑rhombus insert designed for finishing to light external and internal turning of steel, featuring an SU chipbreaker and a 0.8 mm corner radius for low cutting forces and improved surface quality

• Large positive C‑rhombus 80° form
• CVD-coated AC820P, low cutting forces
• SU chipbreaker optimised for finishing
• 0.8 mm corner radius, two usable edges

Cleaner finishing with lower cutting forces

The large positive C‑Rhombus 80° geometry reduces cutting resistance and lowers power draw during light turning operations, which directly benefits cycle times and tool life. The positive rake and the SU chipbreaker produce short, controllable chips suitable for uninterrupted finishing passes, helping to maintain a stable cutting regime. For machining operations where surface quality and dimensional consistency matter, this geometry minimises vibration and supports predictable tool wear, resulting in fewer rework cycles and improved process stability.

Durable coating and material for balanced wear resistance

The insert is made of CVD-coated cemented carbide with the AC820P specification; the CVD Super‑FF‑Coat (Al₂O₃/TiCN) with a layer thickness of about 14 µm offers a combination of wear resistance and fracture toughness. With a measured hardness of 90.1 HRA and a flexural strength of approximately 2.2 GPa, the grade is engineered for steady performance in finishing and light turning of steel. Recommended cutting data supports efficient operation at Vc 190–310 m/min (optimum 250 m/min) with feeds in the range f 0.07–0.30 mm/U; these parameters help exploit the coating’s strengths while avoiding aggressive conditions for which this grade is not intended.

Integration and economy for day-to-day production

The insert’s 0.8 mm corner radius and two usable edges provide a practical balance between edge strength and fine finish capability, reducing tool change frequency and inventory complexity. The cylindrical hole with one‑side countersink and the neutral cutting direction support secure mounting in common turning toolholders, while the 4.76 mm plate thickness contributes to stable clamping and repeatable positioning. With recommended depth of cut ap 0.5–2.5 mm and a clear specification window for feeds, the component integrates smoothly into established turning cycles and is supplied in a standard unit of 10 pieces for predictable replenishment.

Contact Metav Werkzeuge for application-specific recommendations on the Sumitomo CCMT120408N-SU AC820P insert or to check current availability; phone +49 2822 7131930 or email info@metav-werkzeuge.com

Technical data

• Article number: 207117-Sumitomo
• Manufacturer SKU: CCMT120408N-SU AC820P
• Product type: Indexable turning insert
• Article name: Sumitomo CCMT120408N-SU AC820P Wendeschneidplatte

Facts

• Geometry: C‑Rhombus 80°
• Cutting angle / tip angle: 80°
• Clearance angle: 7°
• Corner radius: 0.8 mm
• Plate thickness: 4.76 mm
• Cutting edges: 2 usable edges
• Cutting length: 12.9 mm
• Inner circle: 12.7 mm
• Tolerance class: M
• Hardness: 90.1 HRA
• Flexural strength: ~2.2 GPa
• Recommended ap: 0.5–2.5 mm
• Recommended feed f: 0.07–0.30 mm/U
• Cutting speed Vc: 190–310 m/min (optimum 250 m/min)
• Packaging unit: 10 pieces

Special features

• Material: CVD-coated cemented carbide
• Coating: CVD Super‑FF‑Coat (Al₂O₃/TiCN), ~14 µm
• Chipbreaker: SU (single-sided, positive chip geometry)
• Hole style: Cylindrical hole with one-sided countersink
• Application: Finishing to light external and internal turning of steel
• Strengths: Low cutting forces, large positive form, balanced wear and fracture resistance
• Limits: Not intended for heavy interrupted cuts, aggressive roughing, or primary stainless steel applications
• Origin: Japan

FAQ

What materials is this insert suitable for? The CCMT120408N-SU AC820P insert is optimised for finishing and light turning of steel, with the coating and geometry tuned to low cutting forces and stable wear behaviour in those applications.

Can this grade be used for heavy interrupted cuts or roughing? No; the AC820P CVD grade and the positive SU geometry are designed for finishing and light machining. Heavy interrupted cuts or aggressive roughing exceed the recommended operating envelope for this insert.

What are the recommended cutting parameters for efficient finishing? Recommended ranges are Vc 190–310 m/min (optimum 250 m/min) with feeds f 0.07–0.30 mm/U and depths of cut ap 0.5–2.5 mm, which leverage the coating and geometry for consistent surface quality.

How many usable edges does the insert offer and what is the corner radius? The insert provides two usable cutting edges and a corner radius of 0.8 mm, balancing edge strength with the capacity to achieve fine surface finishes.

Does the insert require a special toolholder due to the hole style? The cylindrical hole with a one-sided countersink is compatible with common clamping systems for CCMT-style inserts; secure seating and correct tightening in a suitable holder ensure repeatable performance.

Manufacturer/Responsible: Sumitomo Electric Hardmetal Corp., 1-1-1, Koyakita, Itami, Hyogo 664-0016 (in Itami Works of Sumitomo Electric Industries, Ltd.)