Machine Tap ISO 529 Form B HSS-G with Interrupted Threads
Machine Tap ISO 529 Form B HSS-G with Interrupted Threads
The VÖLKEL Machine Tap with interrupted threads according to ISO 529 Form B is the perfect solution for precise and efficient thread cutting in through holes.
Thanks to the interrupted thread design, cutting forces are reduced, chip flow is improved, and tool life is extended.
Made from HSS-G (ground high-speed steel), it is ideal for unalloyed and low alloy steels as well as machinable materials up to 900 N/mm².
ISO 529 is the international standard that specifies the dimensions and tolerances of hand and machine taps. It distinguishes between
different lead forms: Form A (long), Form B (medium), Form C (short, for blind holes), and Form D (extra short, for deep blind holes).
The Form B used here is especially versatile and commonly chosen for through holes.
With its interrupted threads and HSS-G design, this machine tap combines precision, durability and efficiency – making it a trusted tool in both workshop and industrial applications.
- For general use in workshops and industry
- Optimized for through holes
- Suitable for both manual and machine use
- Materials: steels up to 900 N/mm², unalloyed and low alloyed
Interrupted threads provide multiple advantages:
- Lower cutting forces → less risk of breakage
- Improved chip evacuation → cleaner threads and reduced rework
- Longer tool life → fewer tool changes, higher efficiency
The ISO 529 standard defines machine tap dimensions and tolerances. Form B offers:
- Medium lead with approx. 3.5–5 threads
- Universal application in through holes
- Comparison: Form A = long, Form B = medium, Form C = short, Form D = extra short
- Preparation: Drill the correct core hole, deburr, and prepare cutting oil.
- Clamping: Fix the tap securely and align it perpendicular to the hole.
- Starting: Begin slowly and apply even pressure until the first threads are cut.
- Cutting: Use cutting oil to reduce wear. Interrupted threads improve chip flow and precision.
- Finishing: Reverse the tap out carefully, clean the hole, and check with a thread gauge.
Q1: What does ISO 529 mean?
A1: ISO 529 is the standard for hand and machine taps, specifying sizes, tolerances and lead forms.
Q2: What is Form B used for?
A2: Form B has a medium lead, making it ideal for through holes. It is the most common form in workshops.
Q3: How do interrupted threads help?
A3: They reduce cutting forces, improve chip evacuation and extend tool life.
Q4: Can this tap be used by hand?
A4: Yes, it is suitable for both manual and machine use.
Q5: Which materials can I use it on?
A5: It is suitable for machinable materials up to 900 N/mm², especially unalloyed and low alloyed steels.
Do you want to know more about the VÖLKEL Machine Tap with interrupted threads or need advice on the right application?
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