| Thread | Whitworth-pipe tread acc. DIN 2999 |
| Abbreviation | Rp / R |
| Designation | DIN 2999-Rp-1/2 DIN 2999-R-1/2-1 |
| Type of thread | inside thread cylindric outside thread conical (cone 1:16) |
| Application | Pipe thread, to suit pipe threads and fittings, with sealant (see page 10), sealing in the thread |
| Description | The conical R-outside thread shows at the relating level &147;. The adjustment power created by using of a suitable tool increases the thread reach and seals the screw connection supported by a suitable sealant (e.g. hemp or Teflon). |
| Comparison with DIN/ISO 228 | The cylindric Rp-inner thread of this norm shows the same dimensions of the diameters and of the thread profile as the cylindric inner thread acc. DIN/ISO 228, however the G-inner thread shows concerning the core and effective diameter positive dimensions only (at DIN 2999 ±tolerance). Therefore a DIN 2999-R-conical outside thread can be screwed into a ISO 228-G-cylindric inner thread. However the outside thread can be approx. screwed in 1 furthermore thread-turn opening at the G-thread a larger free space between the crest of thread and with that a larger leakage space caused by the bigger tolerance of the core diameter. |
| Never combine | ISO 228-G-cyl. outside thread with DIN 2999-Rp-cyl. inside thread. The inside thread could be possibly to small. |
| DIN | outside thread R | inside thread Rp | outside Ø of pipe | number of threads | P | h | outside Ø | effective Ø | core Ø | a | i |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 6 | R 1/8" | Rp 1/8" | 10.2 | 28 | 0.907 | 0.581 | 9.728 | 9.147 | 8.566 | 4 | 6.5 |
| 8 | R 1/4" | Rp 1/4" | 13.5 | 19 | 1.337 | 0.856 | 13.157 | 12.301 | 11.445 | 6 | 9.7 |
| 10 | R 3/8" | Rp 3/8" | 17.2 | 19 | 1.337 | 0.856 | 16.662 | 15.806 | 14.95 | 6.4 | 10.1 |
| 15 | R 1/2" | Rp 1/2" | 21.3 | 14 | 1.814 | 1.162 | 20.955 | 19.793 | 18.631 | 8.2 | 13.2 |
| 20 | R 3/4" | Rp 3/4" | 26.9 | 14 | 1.814 | 1.162 | 26.441 | 25.279 | 24.117 | 9.5 | 14.5 |
| 25 | R 1" | Rp 1" | 33.7 | 11 | 2.309 | 1.479 | 33.249 | 31.77 | 30.291 | 10.4 | 16.8 |
| 32 | R 1 1/4" | Rp 1 1/4" | 42.4 | 11 | 2.309 | 1.479 | 41.91 | 40.431 | 38.952 | 12.7 | 19.1 |
| 40 | R 1 1/2" | Rp 1 1/2" | 48.3 | 11 | 2.309 | 1.479 | 47.803 | 46.324 | 44.845 | 12.7 | 19.1 |
| 50 | R 2" | Rp 2" | 60.3 | 11 | 2.309 | 1.479 | 59.614 | 58.135 | 56.656 | 15.9 | 23.4 |
| 65 | R 2 1/2" | Rp 2 1/2" | 76.1 | 11 | 2.309 | 1.479 | 75.184 | 73.705 | 72.226 | 17.5 | 26.7 |
| 80 | R 3" | Rp 3" | 88.9 | 11 | 2.309 | 1.479 | 87.884 | 86.341 | 84.926 | 20.6 | 29.8 |
| 100 | R 4" | Rp 4" | 114.3 | 11 | 2.309 | 1.479 | 113.03 | 111.551 | 110.072 | 25.4 | 35.8 |
| 125 | R 5" | Rp 5" | 139.7 | 11 | 2.309 | 1.479 | 138.43 | 136.951 | 135.472 | 28.6 | 40.1 |
| 150 | R 6" | Rp 6" | 165 | 11 | 2.309 | 1.479 | 163.83 | 162.351 | 160.872 | 28.6 | 40.1 |