O-Rings
Additional Information
There are several different standards to choose from when it comes to O-ring dimensions. The most popular in the United States is the AS568 standard for O-ring sizes and tolerances. Maintained by the Society of Automotive Engineers, this standard allows the user to choose from five different cross-sections with inside diameters ranging from 1/32" to 26". Tube fitting boss seals are included in AS568 as 900 series O-ring sizes, and are intended for use in MS33649 (now superseded by SAE-AS5202) straight thread tube fitings. RT/Dygert also offers a wide array of metric sizes, in both standard and non-standard dimensions. As a subset of the metric sizes offered, we also stock many Japanese Industrial Standard (JIS B2401) sizes. If an O-ring with special size or fluid resistance is required, RT/Dygert can provide custom O-rings, specially made to your demanding requirements.
SIZES
| Dimensions in Inches | Nominal Size (Reference Only) | |||||||
| ID | AS568A | I.D. | ± | C/S | Vol (in3) | I.D. | O.D. | C/S |
| 1397 | 309 | 0.412 | .005 | .210 ± .005 | .0677 | 7/16 | 13/16 | 3/16 |
| 1398 | 310 | 0.475 | .005 | .210 ± .005 | .0745 | 1/2 | 7/8 | 3/16 |
| 1399 | 311 | 0.537 | .007 | .210 ± .005 | .0813 | 9/16 | 15/16 | 3/16 |
| 1400 | 312 | 0.6 | .009 | .210 ± .005 | .0881 | 5/8 | 1 | 3/16 |
| 1401 | 313 | 0.662 | .009 | .210 ± .005 | .0949 | 11/16 | 1-1/16 | 3/16 |
| 1402 | 314 | 0.725 | .010 | .210 ± .005 | .1017 | 3/4 | 1-1/8 | 3/16 |
| 1403 | 315 | 0.787 | .010 | .210 ± .005 | .1085 | 13/16 | 1-3/16 | 3/16 |
| 1404 | 316 | 0.85 | .010 | .210 ± .005 | .1153 | 7/8 | 1-1/4 | 3/16 |
| 1405 | 317 | 0.912 | .010 | .210 ± .005 | .1221 | 15/16 | 1-5/16 | 3/16 |
| 1406 | 318 | 0.975 | .010 | .210 ± .005 | .1289 | 1 | 1-3/8 | 3/16 |
| 1407 | 319 | 1.037 | .010 | .210 ± .005 | .1357 | 1-1/16 | 1-/7/16 | 3/16 |
| 1408 | 320 | 1.1 | .012 | .210 ± .005 | .1425 | 1-1/8 | 1-1/2 | 3/16 |
| 1409 | 321 | 1.162 | .012 | .210 ± .005 | .1493 | 1-3/16 | 1-9/16 | 3/16 |
| 1410 | 322 | 1.225 | .012 | .210 ± .005 | .1561 | 1-1/4 | 1-5/8 | 3/16 |
| 1411 | 323 | 1.287 | .012 | .210 ± .005 | .1629 | 1-5/16 | 1-11/16 | 3/16 |
| 1412 | 324 | 1.35 | .012 | .210 ± .005 | .1697 | 1-3/8 | 1-3/4 | 3/16 |
| 1413 | 325 | 1.475 | .015 | .210 ± .005 | .1833 | 1-1/2 | 1-7/8 | 3/16 |
| 1414 | 326 | 1.6 | .015 | .210 ± .005 | .1970 | 1-5/8 | 2 | 3/16 |
| 1415 | 327 | 1.725 | .015 | .210 ± .005 | .2106 | 1-3/4 | 2-1/8 | 3/16 |
| 1416 | 328 | 1.85 | .015 | .210 ± .005 | .2242 | 1-7/8 | 2-1/4 | 3/16 |
| 1417 | 329 | 1.975 | .018 | .210 ± .005 | .2378 | 2 | 2-3/8 | 3/16 |
| 1418 | 330 | 2.1 | .018 | .210 ± .005 | .2514 | 2-1/8 | 2-1/2 | 3/16 |
| 1419 | 331 | 2.225 | .018 | .210 ± .005 | .2650 | 2-1/4 | 2-5/8 | 3/16 |
| 1420 | 332 | 2.35 | .018 | .210 ± .005 | .2789 | 2-3/8 | 2-3/4 | 3/16 |
| 1421 | 333 | 2.475 | .020 | .210 ± .005 | .2922 | 2-1/2 | 2-7/8 | 3/16 |
| 1422 | 334 | 2.6 | .020 | .210 ± .005 | .3058 | 2-5/8 | 3 | 3/16 |
| 1423 | 335 | 2.725 | .020 | .210 ± .005 | .3194 | 2-3/4 | 3-1/8 | 3/16 |
| 1424 | 336 | 2.85 | .020 | .210 ± .005 | .3330 | 2-7/8 | 3-1/4 | 3/16 |
| 1425 | 337 | 2.975 | .024 | .210 ± .005 | .3466 | 3 | 3-3/8 | 3/16 |
| 1426 | 338 | 3.1 | .024 | .210 ± .005 | .3602 | 3-1/8 | 3-1/2 | 3/16 |
| 1427 | 339 | 3.225 | .024 | .210 ± .005 | .3738 | 3-1/4 | 3-5/8 | 3/16 |
| 1428 | 340 | 3.35 | .024 | .210 ± .005 | .3874 | 3-3/8 | 3-3/4 | 3/16 |
| 1429 | 341 | 3.475 | .024 | .210 ± .005 | .4010 | 3-1/2 | 3-7/8 | 3/16 |
| 1430 | 342 | 3.6 | .028 | .210 ± .005 | .4146 | 3-5/8 | 4 | 3/16 |
| 1431 | 343 | 3.725 | .028 | .210 ± .005 | .4282 | 3-3/4 | 4-1/8 | 3/16 |
| 1432 | 344 | 3.85 | .028 | .210 ± .005 | .4418 | 3-7/8 | 4-1/4 | 3/16 |
| 1433 | 345 | 3.975 | .028 | .210 ± .005 | .4554 | 4 | 4-3/8 | 3/16 |
| 1434 | 346 | 4.1 | .028 | .210 ± .005 | .4690 | 4-1/8 | 4-1/2 | 3/16 |
| 1435 | 347 | 4.225 | .030 | .210 ± .005 | .4826 | 4-1/4 | 4-5/8 | 3/16 |
| 1436 | 348 | 4.35 | .030 | .210 ± .005 | .4962 | 4-3/8 | 4-3/4 | 3/16 |
| 1437 | 349 | 4.475 | .030 | .210 ± .005 | .5098 | 4-1/2 | 4-7/8 | 3/16 |
| 1438 | 350 | 4.6 | .030 | .210 ± .005 | .5234 | 4-5/8 | 5 | 3/16 |
| 1439 | 351 | 4.725 | .030 | .210 ± .005 | .5370 | 4-3/4 | 5-1/8 | 3/16 |
| 1440 | 352 | 4.85 | .030 | .210 ± .005 | .5506 | 4-7/8 | 5-1/4 | 3/16 |
| 1441 | 353 | 4.975 | .037 | .210 ± .005 | .5642 | 5 | 5-3/8 | 3/16 |
| 1442 | 354 | 5.1 | .037 | .210 ± .005 | .5778 | 5-1/8 | 5-1/2 | 3/16 |
| 1443 | 355 | 5.225 | .037 | .210 ± .005 | .5914 | 5-1/4 | 5-5/8 | 3/16 |
| 1444 | 356 | 5.35 | .037 | .210 ± .005 | .6050 | 5-3/8 | 5-3/4 | 3/16 |
| 1445 | 357 | 5.475 | .037 | .210 ± .005 | .6186 | 5-1/2 | 5-7/8 | 3/16 |
| 1446 | 358 | 5.6 | .037 | .210 ± .005 | .6322 | 5-5/8 | 6 | 3/16 |
| 1447 | 359 | 5.725 | .037 | .210 ± .005 | .6458 | 5-3/4 | 6-1/8 | 3/16 |
| 1448 | 360 | 5.85 | .037 | .210 ± .005 | .6594 | 5-7/8 | 6-1/4 | 3/16 |
| 1449 | 361 | 5.975 | .037 | .210 ± .005 | .6730 | 6 | 6-3/8 | 3/16 |
| 1450 | 362 | 6.225 | .040 | .210 ± .005 | .7002 | 6-1/4 | 6-5/8 | 3/16 |
| 1451 | 363 | 6.475 | .040 | .210 ± .005 | .7274 | 6-1/2 | 6-7/8 | 3/16 |
| 1452 | 364 | 6.725 | .040 | .210 ± .005 | .7546 | 6-3/4 | 7-1/8 | 3/16 |
| 1453 | 365 | 6.975 | .040 | .210 ± .005 | .7818 | 7 | 7-3/8 | 3/16 |
| 1454 | 366 | 7.225 | .045 | .210 ± .005 | .8090 | 7-1/4 | 7-5/8 | 3/16 |
| 1455 | 367 | 7.475 | .045 | .210 ± .005 | .8362 | 7-1/2 | 7-7/8 | 3/16 |
| 1456 | 368 | 7.725 | .045 | .210 ± .005 | .8634 | 7-3/4 | 8-1/8 | 3/16 |
| 1457 | 369 | 7.975 | .045 | .210 ± .005 | .8906 | 8 | 8-3/8 | 3/16 |
| 1458 | 370 | 8.225 | .050 | .210 ± .005 | .9178 | 8-1/4 | 8-5/8 | 3/16 |
| 1459 | 371 | 8.475 | .050 | .210 ± .005 | .9450 | 8-1/2 | 8-7/8 | 3/16 |
| 1460 | 372 | 8.725 | .050 | .210 ± .005 | .9722 | 8-3/4 | 9-1/8 | 3/16 |
| 1461 | 373 | 8.975 | .050 | .210 ± .005 | .9994 | 9 | 9-3/8 | 3/16 |
| 1462 | 374 | 9.225 | .055 | .210 ± .005 | 1.0266 | 9-1/4 | 9-5/8 | 3/16 |
| 1463 | 375 | 9.475 | .055 | .210 ± .005 | 1.0538 | 9-1/2 | 9-7/8 | 3/16 |
| 1464 | 376 | 9.725 | .055 | .210 ± .005 | 1.0810 | 9-3/4 | 10-1/8 | 3/16 |
| 1465 | 377 | 9.975 | .055 | .210 ± .005 | 1.1083 | 10 | 10-3/8 | 3/16 |
| 1466 | 378 | 10.475 | .060 | .210 ± .005 | 1.1627 | 10-1/2 | 10-7/8 | 3/16 |
| 1467 | 379 | 10.975 | .060 | .210 ± .005 | 1.2171 | 11 | 11-3/8 | 3/16 |
| 1468 | 380 | 11.475 | .065 | .210 ± .005 | 1.2737 | 11-1/2 | 11-7/8 | 3/16 |
| 1469 | 381 | 11.975 | .065 | .210 ± .005 | 1.2715 | 12 | 12-3/8 | 3/16 |
| 1470 | 382 | 12.975 | .065 | .210 ± .005 | 1.3259 | 13 | 13-3/8 | 3/16 |
| 1471 | 383 | 13.975 | .070 | .210 ± .005 | 1.4347 | 14 | 14-3/8 | 3/16 |
| 1472 | 384 | 14.975 | .070 | .210 ± .005 | 1.5435 | 15 | 15-3/8 | 3/16 |
| 1473 | 385 | 15.955 | .075 | .210 ± .005 | 1.6523 | 16 | 16-3/8 | 3/16 |
| 1474 | 386 | 16.955 | .080 | .210 ± .005 | 1.7590 | 17 | 17-3/8 | 3/16 |
| 1475 | 387 | 17.955 | .085 | .210 ± .005 | 1.9766 | 18 | 18-3/8 | 3/16 |
| 1476 | 388 | 18.955 | .090 | .210 ± .005 | 2.0854 | 19 | 19-3/8 | 3/16 |
| 1477 | 389 | 19.955 | .095 | .210 ± .005 | 2.1942 | 20 | 20-3/8 | 3/16 |
| 1478 | 390 | 20.955 | .095 | .210 ± .005 | 2.3030 | 21 | 21-3/8 | 3/16 |
| 1479 | 391 | 21.955 | .100 | .210 ± .005 | 2.4118 | 22 | 22-3/8 | 3/16 |
| 1480 | 392 | 22.94 | .105 | .210 ± .005 | 2.5190 | 23 | 23-3/8 | 3/16 |
| 1481 | 393 | 23.94 | .110 | .210 ± .005 | 2.6278 | 24 | 24-3/8 | 3/16 |
| 1482 | 394 | 24.94 | .115 | .210 ± .005 | 2.7366 | 25 | 25-3/8 | 3/16 |
| 1483 | 395 | 25.94 | .120 | .210 ± .005 | 2.8454 | 26 | 26-3/8 | 3/16 |
MATERIALS
Silicone Rubber
RT/Dygert Stock Material
Other Designations
Silastic® (Dow Corning); MQ; VMQ; PMQ
Composition
Medium density inorganic rubber primarily consisting of polymethylsiloxane and variations
Temperature Range
-65 to 450 °F
Description
Silicone Rubber is an inorganic rubber whose ability to retain its physical properties at elevated temperatures is superior to most other materials. It is also flexible at very low temperatures however its relatively poor tensile, tear strength and abrasion resistance limits use to static applications. These weaknesses can be improved somewhat by reinforcement with fine, high surface area fillers which are compatible chemically with the silicone polymer itself. Silicone does possess extraordinary resistance to oxidation and ozone degradation due to the absence of unsaturated double bonds in the polymer backbone. Since it is fully saturated, only peroxides can be used for hot vulcanization processes. Resistance of silicone vulcanizates to gas permeation is generally considered to be poor, as much as 100 times greater than nitrile or butyl, but it is frequently specified in food and beverage applications as it does not impart any taste or odor. However, the automotive industry accounts for almost 50% of silicone usage in the U.S. annually.
Information above applies to the generic material. Specific compounds may exhibit different properties.
Physical Properties*
| Excellent | Good | Fair | Poor | |
| Abrasion resistance | • | |||
| Compression Set | • | |||
| Elongation | • | |||
| Flame resistance | • | |||
| Gas permeability | • | |||
| Low temperature flexibility | • | |||
| Tear resistance | • | |||
| Tensile strength | • |
Chemical Resistance*
| Excellent | Good | Fair | Poor | |
| Dilute acids | • | |||
| Dilute alkalis | • | |||
| Ketones | • | |||
| Ozone | • | |||
| Petroleum oils | • | |||
| Steam | • | |||
| Vegetable oils | • | |||
| Water | • | |||
| Weather | • |
*Excellent, good, fair and poor are intended to serve as general guidelines only. Actual testing in the application environment is always recommended.
Information above applies to the generic material. Specific compounds may exhibit different properties.