1. Product Specifications

This document details technical specifications for twist drills with internal coolant channels, designed specifically for steel drilling. The drills range in diameter from 1.00 mm to 20.00 mm, with precision tolerance classes m7 and h7. Key dimensional parameters include:

• Diameter (Dc): 1.00 mm to 20.00 mm, with increments of 0.10 or 0.20 mm depending on series.
• Lengths: L1 (cutting length) and L2 (overall length), both increasing with drill size and series, ranging from 15 mm to 190 mm for L1 and 55 mm to 243 mm for L2.
• D2: Shank diameter, varying between 3 mm and 20 mm.

The drills are made from high-speed steel (HM) with micrograin carbide grades K20-K40, conforming to DIN 6527 standards. Geometry features include a 140° point angle (HA) and a 30° helix angle, optimized for steel machining. Internal coolant channels enhance cooling and chip evacuation.

2. Product Series and Variants

The drills are organized into series based on length and application depth:

• 178 3XD Series: Shorter drills for standard drilling depths.
• 178 5XD Series: Medium length drills for deeper holes.
• 178 8XD Series: Longer drills for deep hole drilling.
• 178 12XD Series: Longest drills for very deep drilling tasks.

3. Dimensional Data and Tables

Extensive tables provide drill codes, diameters, tolerance classes, cutting lengths (L1), overall lengths (L2), and shank diameters (D2). These enable precise drill selection tailored to specific machining requirements.

4. Key Technical Parameters

• Tolerance Classes: m7 and h7 ensure tight diameter control for precision machining.
• Material Grades: Micrograin carbide K20-K40 offers high wear resistance and durability.
• Standard Compliance: DIN 6527 guarantees quality and compatibility.
• Geometry: 140° point angle and 30° helix angle optimize cutting efficiency and chip removal in steel.

5. Recommendations and Usage Guidelines

• Select drill series (3XD, 5XD, 8XD, 12XD) based on required drilling depth.
• Ensure coolant supply through internal channels for optimal tool life and performance.
• Choose tolerance class (m7 or h7) according to precision needs.
• Adhere to DIN 6527 standards for mounting and usage to maintain tool integrity.

Conclusion

This document serves as a comprehensive technical reference for selecting high-quality twist drills with internal coolant for steel machining. It covers a broad range of diameters, lengths, tolerance classes, and material specifications to ensure optimal drilling performance and durability.