Threading tools from the manufacturer
This is the complete VÖLKEL range for cutting and forming threads: hand taps and machine taps for internal threads, round dies for external threads, fluteless forming taps for chipless production, and the matching tap wrenches and die holders. More than 8,000 articles cover metric coarse and fine threads, inch threads (BSW, BSF, UNC, UNF, UNEF), pipe threads (G, R, NPT), trapezoidal threads and left-hand threads.
Which tap for which job?
Start with the drive. If the thread is cut by hand with a tap wrench, a hand tap set is the right choice: taper, second and bottoming tap spread the cutting work over two or three passes. On a machine, a machine tap cuts the thread in one pass; the chamfer form decides whether it is meant for through holes (form B) or blind holes (form C). Short machine taps are the compromise for hand and machine use with a single tool.
Workpiece material
HSS-G is sufficient for structural steels up to about 800 N/mm²; alloyed, stainless and tough materials call for HSSE or powder-metallurgical HSSE-PM. Coatings such as TiN, TiCN or TiAlN extend tool life and allow higher cutting speeds. If you would rather not compare, choose the machine taps with coloured ring: each ring colour stands for a material group, from the green ring for unalloyed steels to the white ring for stainless steels. Read more in HSS, HSSE and HSSE-PM explained.
Internal threads without chips
In materials that form well, such as aluminium, copper alloys or steel up to around 900 N/mm², fluteless forming taps produce the thread by displacing material instead of cutting it. The thread is stronger, the tool lasts longer and there are no chips. The pilot hole must be larger than for cutting.
External threads
For bolts and shafts there are round dies to DIN 223 in HSS, HSSE and HSSE-VAP, plus hexagon die nuts for recutting damaged threads in places a die holder cannot reach.
Sets, bits and accessories
Tap and die sets combine taps, dies and tapping drills in one case. HexTap and combination bits cut threads with a cordless drill. The right tap wrench and die holder are listed under tool holders; the correct tapping drill size is in Calculate tap drill size.
