The hydraulic seal is quite a soft, non-metal ring. Most hydraulic seals will be captured into grooves or set into a combination of rings. All this allows for the formation of a seal assembly. This is necessary in order to block or separate fluid into reciprocating motion applications. The use of hydraulic seals remains important to related industries in the sense that they provide solutions for fluid power to be converted into its required linear motions.
Hydraulic seals are made from a variety of materials. These will include rubber, polyurethane and what is known as PTFE. The material to be used in the construction of the hydraulic seal will be determined by specified operating conditions or set limitations as a result of fluid type, fluid chemical compatibility, pressure or temperature. Other materials under consideration, depending on the circumstances, will be those known as EPDM, NBR, Viton, as well as filled PTFE.
One of the materials, NBR, is the abbreviation or acronym of one of the most commonly used materials known as nitrile rubber.
Here are two types of hydraulic seals being manufactured. One is known as the static seal, while the other is the dynamic seal. The static hydraulic seal will be located in a groove and will experience no movement. The dynamic hydraulic seal is also known as a rod seal. This seal will be exposed to movement within, along the shaft or rod. Confined in space, the static seal acts like a gasket. The gasket needs to be placed under pressure.
This is achieved by way of tightening the attached bolts. In the case of the dynamic seal again, a piston seal will be exposed to movement outside of its diameter, alongside the tube or bore of the hydraulic cylinder.