Pramet HSS DIN335C Standard 3 Flute 90° Countersink Drill Bit for Steel Stainless Aluminum Chamfering and Deburring

HSS DIN335C Pramet is a European standard precision 3-flute countersink manufactured under German DIN335C specification, developed for industrial screw head sinking, hole chamfering and metal deburring. Made of premium M2 high-speed steel with full CBN deep grinding treatment, this 90° conical countersink features three unequal convex cutting edges and straight cylindrical shank, effectively eliminating cutting vibration and burr residues. Compatible with drill presses, CNC milling centers, bench drills and automatic lathes, it performs consistently on carbon steel, stainless steel, cast iron, aluminum alloy and brass, widely adopted in automotive, mold, hydraulic and general hardware mass production.

1. DIN335C standard Form C heavy-duty structure, designed for deep countersinking of cross recessed bolts, hex socket screw heads
2. Premium HSS high-speed steel substrate, balanced hardness and toughness, anti-edge chipping under medium feed continuous cutting
3. 3 unequal optimized flutes, large chip space for smooth swarf evacuation, no chip clogging during long batch processing
4. Full CBN precision grinding on all cutting surfaces, sharp cutting edge, chatter-free machining without vibration ripples on workpiece surface
5. Standard 90° cone angle perfectly matches metric screw head taper; optional 60°/120° angles for special chamfer requirements
6. h9 tolerance straight cylindrical shank, fits all standard ER collets, drill chucks and automatic tool holders without adapter modification
7. Radial back-off clearance design reduces cutting friction, lowers feed resistance and extends overall tool service life

• Full Model: HSS DIN335C
• Brand: Pramet (Dormer Pramet Europe Cutting Tool Brand)
• Executive Standard: DIN 335:2024 Form C
• Raw Material: M2 High Speed Steel (HSS-Co cobalt HSS optional)
• Flute Structure: 3 Unequal Convex Cutting Flutes
• Standard Countersink Angle: 90°
• Shank Style: Solid Cylindrical Straight Shank, Tolerance h9
• Surface Treatment: Bright fully ground finish; TiN/TiAlN coating optional
• Available Size Range: Nominal diameter 4.3mm ~ 40mm, matched standard shank diameter 4mm~16mm
• Compatible Equipment: CNC machining center, vertical drill press, bench drill, CNC automatic lathe

Mild carbon steel, alloy structural steel, 304/316 stainless steel, grey cast iron, ductile iron, aluminum alloy, brass, copper, hard engineering plastics

90° screw head countersinking, hole edge chamfering, cross-hole deburring, surface flash trimming, bolt hole recess processing

1. Automotive manufacturing: engine housing bolt hole sinking, chassis fastener countersinking, brake fitting hole deburring
2. Mold industry: mold base assembly screw chamfering, mold plate positioning hole edge finishing
3. Hydraulic & pneumatic hardware: valve body connecting hole deburr, miniature pipe joint screw head countersink
4. General machinery: gear blank, shaft sleeve, equipment frame bolt hole batch chamfer processing
5. Precision metal fabrication: thin-wall aluminum alloy parts, stainless steel fixture hole burr removal