The design of the seal ring must permit for minimizing distortion and maximizing warmth switch whereas considering the secondary sealing element, drive mechanism, spring and ease of assembly. Many seal rings contain the seal face diameters, although this is not a requirement of the first ring.

Seals with rotating seal rings are mentioned to be 'rotating' seals; seals with stationary seal rings are mentioned to be 'stationary' seals. Because the springs are all the time related to the seal rings, typically the distinction is made as 'rotating springs' versus 'stationary springs'.

In the mid-1940s pump manufacturers such as Ingersoll-Rand, Worthington, Pacific, Byron Jackson, United, Union and others started to make their very own mechanical seals. Eventually most of those corporations obtained out of the seal business however the Byron Jackson seal turned the Borg-Warner seal and the Worthington seal was bought to Chempro (now John Crane - Sealol). When classifying end-face mechanical seals by configuration, the primary consideration is whether there is just one set of sealing faces or a number of units.

In such circumstances, a secondary sealing element could be manufactured from perfluoroelastomer and formed within the form of a wedge, V or U. Secondary sealing parts are gaskets which give sealing between the seal ring and shaft and the mating ring and shaft . Typical secondary sealing components embrace O-rings, wedges or rubber diaphragms.

Stationary seals are additionally used to advantage in massive sizes or at high rotational speeds. Both the seal ring and mating should accommodate secondary sealing components. In some designs, various retainers, sleeves and different elements may include secondary sealing components. Whereas a simple O-ring might require only a groove for fitting, some secondary sealing elements might require mechanical compression. Although O-rings can be found in lots of elastomers, generally an elastomer won't be appropriate with the fluid being sealed or may be considered too expensive.

The secondary sealing parts aren't rotating relative to at least one another. The secondary sealing component for the mating ring is always static axially . Secondary sealing elements for the seal ring are described as being both pusher or non-pusher in the axial path. The time period pusher is utilized to secondary seals that should be pushed forwards and backwards by the movement of the shaft or primary ring whereas non-pusher secondary seals are static and related to bellows seal rings. By definition, the seal ring is the axially flexible member of the tip-face mechanical seal.

If a number of units are used, are the units configured to be unpressurized or pressurized. Either the seal ring or the mating ring will be the rotating component.

For convenience, rotating seals are used in most tools; nonetheless, stationary seals have some advantages over rotating seals. In small, mass-produced seals for modest providers, the entire seal may be placed in a bundle which minimizes shaft and housing necessities for the equipment.