The VÖLKEL HSSE Machine Tap DIN 374 Form B – M 50 × 2.0 is your powerful tool for precise and efficient cutting of large metric fine threads in through-holes, whether by hand or machine. Optimized for machine use, it delivers consistently high-quality threads in easily machinable steels and other materials.
Made from HSSE (high-speed steel with at least 5% cobalt content), this tap offers outstanding performance, especially at high cutting temperatures and in more demanding materials. The cobalt addition significantly increases heat resistance and wear resistance, resulting in longer tool life and better cutting performance.
Your Application Benefits:
Versatile Use: Ideal for general applications in easily machinable materials up to 900 N/mm².
Steel Machining: Especially suitable for unalloyed and low-alloy steels.
Perfect for Through-Holes: Form B is designed to transport chips efficiently forward out of the hole.
Large Fine Thread: Cuts a precise M 50 × 2.0 metric ISO fine thread.
This tap is a specialist for large fine threads and guarantees standard-compliant fitting with ISO 2 / 6H tolerance.
DIN 374 – Standard for Machine Taps for Fine Threads
DIN 374 is a German industrial standard specifying dimensions and requirements for machine taps with chamfer forms for metric ISO fine threads. Unlike DIN 371 (coarse threads up to M10) and DIN 376 (coarse threads from M12), DIN 374 is explicitly intended for metric ISO fine thread taps.
Geometry and Tolerances:
DIN 374 defines characteristics such as overall length, thread length, shank diameter, square dimensions, chamfer forms (e.g., Form B), and tolerances.
DIN 13 – The Metric ISO Thread
DIN 13 is a key standard defining dimensions and tolerances for metric ISO threads. It is internationally recognized and forms the basis of metric threading in mechanical engineering. It covers both coarse (M) and fine threads (Mf). Your tap cuts a M 50 × 2.0 thread — classified as a fine thread due to its smaller pitch compared to the coarse standard of 5.5 mm for M50.
Form B – The Specialist for Through-Holes
Form B features straight flutes and a medium-length chamfer (typically 3.5–5 threads). This geometry is optimized to push chips forward out of the hole, preventing clogging and ensuring a smooth, continuous cutting process.
Comparison with Other Forms:
Form C/D (Spiral flutes): Designed for blind holes, pulls chips backward.
Form A/E (Straight flutes with special chamfers): Used for special applications.
Through-Hole vs Blind Hole:
Your Form B tap is ideal for through-holes due to its chip transport efficiency.
Application:
for general use
- non abrasive material up to 900 N/mm²
- unalloyed and low alloyed steel
- for through holes
