O Ring Boss Seal Design

O ring sizes are detailed in sae j1926.

O ring boss seal design.

In order to seal properly the o ring has to deform in the application by being compressed and stretched in any number of ways. The o ring in the face of the straight thread male end seals against the flat face female seat and is mechanically held in place by a swivel nut. These charts list port dimensions per as5202 and j1926 and fitting ends per as4395. 4 5 boss seals the as568 901 through 932 o ring sizes parker s 3 series are intended to be used for sealing straight thread tube fi ttings in a boss.

Design table 4 3 and design table 4 4 show the two standard boss designs that are used for this purpose. The design of the groove where the o ring sits plays a major role in how the o ring performs its sealing role. A standard application for an o ring is sealing a tube fitting. Both of these bosses use the same o ring but parker seal.

Designing the parts of an application where o rings will be applied is broadly termed o ring groove design. There are industry standards for boss fittings with a series of o rings corresponding to each boss size. As4395 is a fitting end that corresponds with as5202 bosses. The design charts below show the standard boss designs that are used for this purpose.