GREEN RING: the all-rounder for steel
The green ring on the shank stands for the largest material group in everyday work: unalloyed steels up to 1,000 N/mm², plus free-cutting and case-hardening steels, malleable cast iron and thermoplastics. If you would rather not compare specifications for every job, this is where you reach first. VÖLKEL makes 104 versions to DIN 371, DIN 376 and JIS B-4430 from HSSE, in form B and form C, from M 2 x 0.4 to M 30 x 3.5.
GREEN RING TwinBox Machine Tap + Twist Drill, DIN 371, Form B, HSS-E, M 10 x 1.5
GREEN RING TwinBox Machine Tap + Twist Drill, DIN 371, Form B, HSS-E, M 4 x 0.7
GREEN RING TwinBox Machine Tap + Twist Drill, DIN 371, Form B, HSS-E, M 5 x 0.8
GREEN RING TwinBox Machine Tap + Twist Drill, DIN 371, Form B, HSS-E, M 6 x 1.0
GREEN RING TwinBox Machine Tap + Twist Drill, DIN 371, Form B, HSS-E, M 8 x 1.25
GREEN RING TwinBox Machine Tap + Twist Drill, DIN 371, Form B, HSS-E, M3 x 0.5
GREEN RING TwinBox Machine Tap + Twist Drill, DIN 376, Form B, HSS-E, M 14 x 2.0
GREEN RING TwinBox Machine Tap + Twist Drill, DIN 376, Form B, HSS-E, M 16 x 2.0
What the green ring covers
Structural steels, free-cutting steels, case-hardening and quenched and tempered steels up to roughly 1,000 N/mm² tensile strength. Plus malleable cast iron and thermoplastics. That covers most of what lands on the bench in general manufacturing.
Form B or form C
Every size comes in both lead forms. Form B with a spiral point lead of four to five threads pushes the chips forward and out of the hole, which suits through holes. Form C with a 39° spiral flute lifts them out to the rear and is made for blind holes. There is also the TwinBox, which pairs the tap with its matching twist drill. Other designs are among the machine taps.
Cutting speed
Guide value for unalloyed steels: 10 to 18 m/min. Use a cutting oil emulsion or cutting oil, with lubricity additives if you like. Suitable products are listed under lubricants.
When another colour is due
As soon as the material gets harder or tougher, the colour changes: BLUE RING for alloyed and tough steels up to 1,200 N/mm², WHITE RING for stainless materials, RED RING for anything above 1,200 N/mm². The full assignment is on the machine taps with coloured ring page, and the background on the high speed steels is in the article HSS, HSSE and HSSE-PM explained.
All sizes at a glance
104 articles in 5 series. The article number links straight to the tool.
Series: Machine Tap GREEN RING JIS B-4430 HSSE · Machine Tap GREEN RING DIN 376 HSSE · Machine Tap GREEN RING DIN 371 HSSE · GREEN RING TwinBox Machine Tap + Twist Drill DIN 371 HSS-E · GREEN RING TwinBox Machine Tap + Twist Drill DIN 376 HSS-E
Machine Tap GREEN RING JIS B-4430 HSSE
| Threadnominal size | Tapping drillØ in mm | Form B | Form C 39° Spiral Flute |
|---|---|---|---|
| M 2 x 0.4 | 1.6 | 91601 | 91801 |
| M 2.3 x 0.4 | 1.9 | 91602 | 91802 |
| M 2.5 x 0.45 | 2.05 | 91603 | 91803 |
| M 2.6 x 0.45 | 2.1 | 91604 | 91804 |
| M 3 x 0.5 | 2.5 | 91605 | 91805 |
| M 3.5 x 0.6 | 2.9 | 91606 | 91806 |
| M 4 x 0.7 | 3.3 | 91607 | 91807 |
| M 5 x 0.8 | 4.2 | 91609 | 91809 |
| M 6 x 0.75 | 5.2 | 91612 | 91812 |
| M 6 x 1.0 | 5 | 91611 | 91811 |
| M 8 x 0.75 | 7.2 | 91624 | 91824 |
| M 8 x 1.0 | 7 | 91614 | 91814 |
| M 8 x 1.25 | 6.8 | 91613 | 91813 |
| M 10 x 1.0 | 9 | 91626 | 91826 |
| M 10 x 1.25 | 8.8 | 91616 | 91816 |
| M 10 x 1.5 | 8.5 | 91615 | 91815 |
| M 12 x 1.0 | 11 | 91627 | 91827 |
| M 12 x 1.25 | 10.8 | 91618 | 91818 |
| M 12 x 1.5 | 10.5 | 91690 | 91890 |
| M 12 x 1.75 | 10.2 | 91617 | 91817 |
| M 14 x 1.25 | 12.8 | 91628 | 91828 |
| M 14 x 1.5 | 12.5 | 91620 | 91820 |
| M 14 x 2.0 | 12 | 91619 | 91819 |
| M 16 x 1.0 | 15 | 91629 | 91829 |
| M 16 x 1.5 | 14.5 | 91622 | 91822 |
| M 16 x 2.0 | 14 | 91621 | 91821 |
| M 18 x 2.5 | 15.5 | 91623 | 91823 |
| M 20 x 2.5 | 17.5 | 91625 | 91825 |
Machine Tap GREEN RING DIN 376 HSSE
| Threadnominal size | Tapping drillØ in mm | Form B | Form C 39° Spiral Flute |
|---|---|---|---|
| M 12 x 1.75 | 10.2 | 35350 | 36350 |
| M 14 x 2.0 | 12 | 35354 | 36354 |
| M 16 x 2.0 | 14 | 35358 | 36358 |
| M 18 x 2.5 | 15.5 | 35362 | 36362 |
| M 20 x 2.5 | 17.5 | 35366 | 36366 |
| M 22 x 2.5 | 19.5 | 35370 | 36370 |
| M 24 x 3.0 | 21 | 35374 | 36374 |
| M 27 x 3.0 | 24 | 35376 | 36376 |
| M 30 x 3.5 | 26.5 | 35378 | 36378 |
Machine Tap GREEN RING DIN 371 HSSE
| Threadnominal size | Tapping drillØ in mm | Form B | Form C 39° Spiral Flute |
|---|---|---|---|
| M 3 x 0.5 | 2.5 | 35326 | 36326 |
| M 4 x 0.7 | 3.3 | 35330 | 36330 |
| M 5 x 0.8 | 4.2 | 35334 | 36334 |
| M 6 x 1.0 | 5 | 35338 | 36338 |
| M 8 x 1.25 | 6.8 | 35342 | 36342 |
| M 10 x 1.5 | 8.5 | 35346 | 36346 |
GREEN RING TwinBox Machine Tap + Twist Drill DIN 371 HSS-E
| Threadnominal size | Tapping drillØ in mm | Form B | Form C 39° SP | Article no. |
|---|---|---|---|---|
| M 3 x 0.5 | 2.5 | 35390 | 36390 | – |
| M 4 x 0.7 | 3.3 | 35391 | 36391 | – |
| M 5 x 0.8 | 4.2 | 35392 | 36392 | – |
| M 6 x 1.0 | 5 | 35393 | 36393 | – |
| M 8 x 1.25 | 6.8 | 35394 | 36394 | – |
| M 10 x 1.5 | 8.5 | 35395 | – | 36395 |
GREEN RING TwinBox Machine Tap + Twist Drill DIN 376 HSS-E
| Threadnominal size | Tapping drillØ in mm | Form B | Form C 39° SP |
|---|---|---|---|
| M 12 x 1.75 | 10.2 | 35396 | 36396 |
| M 14 x 2.0 | 12 | 35397 | 36397 |
| M 16 x 2.0 | 14 | 35398 | 36398 |
Tapping drill: drill diameter recommended by VÖLKEL (Technical Information “Tapping drill sizes”).
