M18 Metric Coarse Thread Machine Tap DIN 376B (6H) HSSE Cobalt Bright

Precision-ground from high-speed steel with 5% cobalt (HSSE), this M18 tap delivers exceptional heat resistance and edge retention for demanding machine tapping operations. The DIN 376B standard with Form B lead (3.5–5 threads) ensures smooth chip evacuation and reduced torque, while the 6H tolerance class guarantees a precise fit for metric coarse threads.

Overview

Engineered for through-hole and blind-hole threading in tough materials, this tap features a straight flute design and right-hand cutting direction. The bright finish provides a clean, uncoated surface that resists chip welding and allows easy inspection. With an overall length of 125 mm and a thread length of 35 mm, it offers ample reach for deep workpieces. The 14 mm shank diameter and 11 mm square drive ensure secure clamping in standard tap holders and quick-change systems.

What stands out

• HSSE cobalt steel withstands high temperatures and maintains hardness for extended tool life.
• Form B lead chamfer (3.5–5 threads) distributes cutting forces evenly, reducing breakage risk.
• 6H tolerance class meets ISO 2 (6H) standards for medium fit, compatible with standard nuts and bolts.
• Straight flutes efficiently evacuate chips in both horizontal and vertical applications.
• Bright finish minimizes friction and allows easy visual inspection of cutting edges.

Technical details

• Thread standard: Metric Coarse (ISO 724)
• Nominal thread diameter: M18
• Thread pitch: 2.5 mm
• Thread tolerance class: 6H
• Tool material: HSSE (High-Speed Steel with Cobalt)
• Standard compliance: DIN 376B
• Lead chamfer form: Form B (3.5-5 threads)
• Flute type: Straight Flute
• Cutting direction: Right-hand
• Overall length (L1): 125 mm
• Thread length (L2): 35 mm
• Shank diameter (d2): 14 mm
• Square drive size (a): 11 mm
• Number of flutes: 4
• Application type: Machine Tapping
• Recommended material: Steel, Stainless Steel, Cast Iron, Non-ferrous Metals
• Finish/Coating: Bright / Uncoated
• Series: 800 Series

Our verdict

With its cobalt-enriched HSSE construction and precision-ground geometry, this tap is a reliable choice for high-volume threading in tough alloys. The DIN 376B compliance and 6H tolerance ensure consistent, accurate threads with minimal tool wear.