
■ On parts made from comparatively soft materials, helical E coil wire thread inserts are often used in order to strengthen internal screws and increase toughness. SP OX STI Oxide produces threads oversize enough to accommodate helical Recommended Tapping Speed depending on Materials coil wire thread inserts. ow carbon steelsBrass
(m/min) For icon explanation, refer to P.50
Segment:1C
| Size | Class | Code | Chamfe | r L | ℓ | ℓn | ℓs | Ds | K | ℓk | No. of l | Type |
| (inch) | (inch) | (inch) | (inch) | (inch) | (inch) | (inch) | flutes | |||||
| For Helical Coil Wire S i | crew Thr i | ead Inserts, for i | Unified Th | i reads | l | |||||||
| GH1 | SUUN2E1NEX | |||||||||||
| STI No.2-56UNC | GH2 | SUUN2E2NEX | 2P | 2.205 | 0.354 | 0.709 | 1.28 | 0.141 | 0.11 | 0.187 | 2 | 1 |
| STI No.4-40UNC | GH1 GH2 | SUUN4H1NEX SUUN4H2NEX | 2P | 2.48 | 0.512 | 0.827 | 1.496 | 0.168 | 0.131 | 0.25 | 2 | 1 |
| STI No.6-32UNC | GH1 GH2 | SUUN6J1NEX SUUN6J2NEX | 2P | 2.756 | 0.551 | 0.945 | 1.654 | 0.194 | 0.131 | 0.25 | 3 | 1 |
| STI No.8-32UNC | GH1 GH2 | SUUN8J1NEX SUUN8J2NEX | 2P | 3.15 | 0.591 | 0.984 | 1.929 | 0.220 | 0.165 | 0.281 | 3 | 1 |
| STI No.10-24UNC | GH2 GH3 | SUUNAM2NEX SUUNAM3NEX | 2P | 3.15 | 0.591 | 1.181 | 1.713 | 0.255 | 0.191 | 0.312 | 3 | 1 |
| STI No.10-32UNF | GH2 GH3 | SUUNAJ2NEX SUUNAJ3NEX | 2P | 3.15 | 0.591 | 1.181 | 1.713 | 0.255 | 0.191 | 0.312 | 3 | 1 |
| STI 1/4-20UNC | GH2 GH3 | SUU04K2NEX SUU04N3NEX | 2P | 3.543 | 0.748 | 1.378 | 1.831 | 0.318 | 0.238 | 0.375 | 3 | 2 |
| STI 1/4-28UNF | GH2 GH3 | SUU04N2NEX SUU04K3NEX | 2P | 3.543 | 0.748 | 1.378 | 1.831 | 0.318 | 0.238 | 0.375 | 3 | 2 |
| STI 5/16-18UNC | GH2 GH3 | SUU05O2NEX SUU05O3NEX | 2P | 3.937 | 0.906 | 1.535 | 2.067 | 0.381 | 0.286 | 0.437 | 3 | 2 |
| STI 5/16-24UNF | GH2 GH3 | SUU05M2NEX SUU05M3NEX | 2P | 3.937 | 0.906 | 1.535 | 2.028 | 0.381 | 0.286 | 0.437 | 3 | 2 |
| STI 3/8-16UNC | GH2 GH3 | SUU06P2NEX SUU06P3NEX | 2P | 4.331 | 1.024 | - | 2.205 | 0.367 | 0.275 | 0.437 | 3 | 3 |
| STI 3/8-24UNF | GH2 GH3 | SUU06M2NEX SUU06M3NEX | 2P | 3.937 | 0.906 | - | 2.008 | 0.323 | 0.242 | 0.406 | 3 | 3 |