4 Flute Coolant Through Step Drill for 304 316L Steel AlTiN Coated Carbide Reamer with Internal Cooling Channels

Our premium 4-flute coolant-through step reamer is specifically engineered for high-performance machining of austenitic stainless steels (304/316L). Featuring advanced AlTiN coating and optimized internal coolant channels, this carbide tool delivers superior hole quality and extended tool life in these notoriously gummy, work-hardening materials.

The unique step drill design combines drilling and reaming operations into one efficient process, significantly reducing cycle times while maintaining IT6-IT7 grade tolerances. Ideal for medical, food processing, and marine applications where 304/316L stainless steels' corrosion resistance is critical.

• 4-flute design with 35° helix angle for optimal chip evacuation
• Polished flute surfaces prevent material adhesion in gummy steels
• Step configuration enables combined roughing/finishing in one pass

• Sub-micron tungsten carbide (0.5μm) for maximum edge stability
• AlTiN nano-coating with enhanced lubricity for stainless steels
• Through-tool coolant (2-4 ports) for effective heat management

• 4 × longer life vs standard HSS reamers in 316L
• Ra 0.8 μm surface finish achievable
• 30% higher feed rates through optimized chip breakers
• Eliminates built-up edge (BUE) common with stainless

• Diameter range: 3-20mm (0.118"-0.787")
• Step configurations: 2-3 steps per tool
• Shank options: Straight, Weldon, hydraulic
• Special features: Left-hand spiral, reduced neck

• Surgical instrument precision holes
• Implant component through-holes

• Valve body machining
• Mixing shaft bearing seats

• Pump housing bores
• Heat exchanger tube plates

• Hydraulic component finishing
• Bearing housing precision bores