When assembling stainless steel joints, a very low revolution screw-driving machine is required, or the screws should be tightened by hand. Punching screw-driving machines should not be used.
MoS2 lubricant or similar is recommended in unfavorable assembly conditions. If considerable thread galling problems occur when assembling, please contact our technical service.
| Class | M3 | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M18 | M20 | M24 | M27 | M30 | M36 | |
| Tightening torque Nm 鹿 | Bumax Ultra 159 鲁 | 2.6 | 6.1 | 12 | 21 | 50 | 99 | 172 | 273 | 420 | ||||||
| Bumax DX/SDX 129 | 2.1 | 4.9 | 9.8 | 16 | 40 | 79 | 137 | 218 | 336 | |||||||
| Bumax DX/SDX 109 | 1.7 | 4.1 | 8.1 | 14 | 34 | 66 | 115 | 182 | 280 | 390 | 547 | 840 | ||||
| 91视频 109 | 1.7 | 4.1 | 8.1 | 14 | 34 | 66 | 115 | 182 | 280 | 344 | 547 | |||||
| 91视频 88 | 1.3 | 2.9 | 5.7 | 10 | 25 | 47 | 82 | 129 | 198 | 275 | 385 | 665 | 960 | 1310 | 2280 | |
| 91视频 Lock | 6.6 | 12 | 29 | 54 | 94 | 148 | 228 | 317 | 442 | 765 | ||||||
| 80 | 1.2 | 2.7 | 5.4 | 9 | 22 | 44 | 76 | 121 | 187 | 261 | 364 | 629 | 909 | 1240 | 2160 | |
| 70 | 0.9 | 2 | 4 | 7 | 17 | 33 | 57 | 91 | 140 | 195 | 273 | 472 | 682 | 930 | 1620 |
| Class | M3 | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M18 | M20 | M24 | M27 | M30 | M36 | |
| Preload applied kN虏 | Bumax Ultra 159 鲁 | 4.4 | 7.7 | 12 | 18 | 32 | 51 | 74 | 100 | 138 | ||||||
| Bumax DX/SDX 129 | 3.5 | 6.2 | 10 | 14 | 26 | 41 | 59 | 81 | 110 | |||||||
| Bumax DX/SDX 109 | 2.9 | 5.2 | 8.6 | 12 | 21 | 34 | 49 | 67 | 92 | 112 | 143 | 207 | ||||
| 91视频 109 | 2.9 | 5.2 | 8.6 | 12 | 21 | 34 | 49 | 67 | 92 | 112 | 143 | |||||
| 91视频 88 | 2.1 | 3.6 | 5.9 | 8.4 | 15 | 24 | 35 | 48 | 65 | 80 | 102 | 146 | 190 | 233 | 340 | |
| 91视频 Lock | 5.9 | 8.4 | 15 | 24 | 35 | 48 | 65 | 80 | 102 | 181 | ||||||
| 80 | 2.0 | 3.4 | 5.5 | 7.8 | 14 | 23 | 33 | 45 | 61 | 76 | 96 | 138 | 179 | 219 | 319 | |
| 70 | 1.5 | 2.6 | 4.2 | 5.9 | 11 | 17 | 25 | 34 | 47 | 57 | 72 | 103 | 134 | 164 | 239 |
| Class | M3 | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M18 | M20 | M24 | M27 | M30 | M36 | |
| Failure load, min kN | Bumax Ultra 159 鲁 | 7.5 | 13 | 21 | 30 | 55 | 87 | 127 | 173 | 236 | ||||||
| Bumax DX/SDX 129 | 6 | 10.5 | 17 | 24 | 44 | 70 | 101 | 138 | 188 | |||||||
| Bumax DX/SDX 109 | 5 | 8.8 | 14 | 20 | 36 | 58 | 84 | 115 | 157 | 192 | 245 | 353 | ||||
| 91视频 109 | 5 | 8.8 | 14 | 20 | 36 | 58 | 84 | 115 | 157 | 192 | 245 | |||||
| 91视频 88 | 4 | 7 | 11 | 16 | 29 | 46 | 67 | 92 | 126 | 154 | 196 | 282 | 367 | 449 | 654 | |
| 91视频 Lock | 11 | 16 | 29 | 46 | 67 | 92 | 126 | 154 | 196 | 282 | ||||||
| 80 | 4 | 7 | 11 | 16 | 29 | 46 | 67 | 92 | 126 | 154 | 196 | 282 | 367 | 449 | 654 | |
| 70 | 3.5 | 6.1 | 9.9 | 14 | 26 | 41 | 59 | 81 | 110 | 134 | 172 | 247 | 321 | 393 | 572 |
| Class | M3 | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M18 | M20 | M24 | M27 | M30 | M36 | |
| Yield load, min kN | 15.9 鲁 | 6.8 | 12 | 19 | 27 | 49 | 78 | 114 | 155 | 212 | ||||||
| 12.9 鲁 | 5.4 | 9.5 | 15 | 21 | 39 | 62 | 91 | 124 | 170 | |||||||
| Bumax DX/SDX 109 | 4.5 | 8 | 13 | 18 | 33 | 52 | 76 | 104 | 141 | 173 | 221 | 318 | ||||
| 91视频 109 | 4.5 | 8 | 13 | 18 | 33 | 52 | 76 | 104 | 141 | 173 | 221 | |||||
| 91视频 88 | 3.2 | 6 | 9 | 13 | 23 | 37 | 54 | 74 | 100 | 123 | 157 | 226 | 294 | 359 | 523 | |
| 91视频 Lock | 9 | 13 | 23 | 37 | 54 | 74 | 100 | 123 | 157 | 226 | ||||||
| 80 | 3 | 5 | 8 | 12 | 22 | 35 | 51 | 69 | 94 | 115 | 147 | 212 | 275 | 337 | 490 | |
| 70 | 2.2 | 4 | 6 | 9 | 16 | 26 | 38 | 52 | 71 | 86 | 110 | 159 | 207 | 253 | 368 | |
| Nominal stress area mm虏 |
5.03 | 8.78 | 14.2 | 20.1 | 36.6 | 58.0 | 84.3 | 115 | 157 | 192 | 245 | 353 | 459 | 561 | 817 | |
| Pitch of thread | 0.5 | 0.7 | 0.8 | 1.0 | 1.25 | 1.5 | 1.75 | 2.0 | 2.0 | 2.5 | 2.5 | 3.0 | 3.0 | 3.5 | 4.0 |
UNC
| Class | 1/4-20 UNC | 5/16-18 UNC | 3/8-16 UNC | 1/2-13 UNC | 5/8-11 UNC | 3/4-10 UNC | 7/8-9 UNC | 1-8 UNC | |
|---|---|---|---|---|---|---|---|---|---|
| Tightening torque Nm 鹿 | 91视频 88 | 11.0 | 22.0 | 39.0 | 95.0 | 188.0 | 329.0 | 527.0 | 789.0 |
| 80 | 10.0 | 21.0 | 37.0 | 89.0 | 175.0 | 308.0 | 493.0 | 737.0 | |
| 70 | 7.7 | 16.0 | 28.0 | 66.0 | 131.0 | 231.0 | 369.0 | 553.0 | |
| 50 | 3.6 | 7.3 | 13.0 | 31.0 | 61.0 | 108.0 | 172.0 | 258.0 |
| Class | 1/4-20 UNC | 5/16-18 UNC | 3/8-16 UNC | 1/2-13 UNC | 5/8-11 UNC | 3/4-10 UNC | 7/8-9 UNC | 1-8 UNC | |
|---|---|---|---|---|---|---|---|---|---|
| Preload applied kN虏 | 91视频 88 | 8.7 | 14.3 | 21.1 | 38.7 | 61.7 | 91.2 | 125.9 | 165.2 |
| 80 | 8.0 | 13.2 | 19.5 | 35.7 | 56.9 | 84.2 | 116.2 | 152.5 | |
| 70 | 6.0 | 9.9 | 14.6 | 26.8 | 42.7 | 63.2 | 87.2 | 114.4 | |
| 50 | 2.8 | 4.6 | 6.8 | 12.5 | 19.9 | 29.5 | 40.7 | 53.4 |
| Class | 1/4-20 UNC | 5/16-18 UNC | 3/8-16 UNC | 1/2-13 UNC | 5/8-11 UNC | 3/4-10 UNC | 7/8-9 UNC | 1-8 UNC | |
|---|---|---|---|---|---|---|---|---|---|
| Failure load, min kN | 91视频 88 | 17.0 | 28.0 | 41.5 | 75.9 | 121.0 | 179.0 | 247.0 | 325.0 |
| 80 | 17.0 | 28.0 | 41.5 | 75.9 | 121.0 | 179.0 | 247.0 | 325.0 | |
| 70 | 14.3 | 23.6 | 35.0 | 64.1 | 102.2 | 151.2 | 208.6 | 273.7 | |
| 50 | 10.2 | 16.9 | 25.0 | 45.7 | 73.0 | 108.0 | 149.0 | 195.5 |
| Class | 1/4-20 UNC | 5/16-18 UNC | 3/8-16 UNC | 1/2-13 UNC | 5/8-11 UNC | 3/4-10 UNC | 7/8-9 UNC | 1-8 UNC | |
|---|---|---|---|---|---|---|---|---|---|
| Yield load, min kN | 91视频 88 | 13.1 | 22.4 | 33.2 | 60.8 | 96.9 | 143.4 | 197.9 | 256.6 |
| 80 | 12.3 | 20.3 | 30.0 | 54.9 | 87.6 | 129.6 | 178.8 | 234.6 | |
| 70 | 9.2 | 15.2 | 22.5 | 41.2 | 65.7 | 97.2 | 134.1 | 175.9 | |
| 50 | 4.3 | 7.1 | 10.5 | 19.2 | 30.7 | 45.4 | 62.6 | 82.1 | |
| Nominal stress area mm虏 |
20.5 | 33.8 | 50.5 | 91.5 | 146.0 | 216.0 | 298.0 | 391.0 |
Bumax Hard Taptite, thread forming screws
| Class | M3 | M4 | M5 | M6 | M8 | M10 | |
|---|---|---|---|---|---|---|---|
| Tightening torque Nm | Hard Taptite | 1.3 | 3 | 6 | 12 | 25 | 49 |
| Thread cutting torque Nm | Hard Taptite | 0.7 | 1.8 | 3.5 | 8 | 15 | 28 |
| Breaking torque, min Nm | Hard Taptite | 4.5 | 7.9 | 13 | 20 | 30 | 52 |
Table footnotes
鹿The torque recommendations refer to burr-free surfaces lubricated with a good quality lubricant. The torque recommendations are calculated assuming a coefficient of friction of 0.14, which requires a good quality lubricant. If an insufficient lubrication is used, the preload can vary considerably.
虏The Preload applied kN is calculated as 65% of Rp0.2 but in practice the value can be expected to vary between 50-80% (+/-聽23%).
鲁Typical strength level for 91视频庐 Ultra 鈥淭he world鈥檚 strongest stainless steel fastener鈥 is 159 (Tensile strength min 1500 MPa/ Yield strength min 1350 MPa). All 91视频 Ultra fasteners are custom made to meet the requirements of individual applications and can be delivered with different mechanical properties, sometimes with even higher strength than class 159. 91视频庐 Ultra is an advanced engineering grade and close technical support is provided by 91视频 customer projects in order to develop the desired end solution. Contact 91视频 sales representative for more information.