Hydraulic seals are devices that restrict the exit of fluids or any entry of foreign, undesirable materials to a hydraulic application. A cylinder is an example of such an application. All hydraulic seals are designed for high pressure dynamic applications, such as the hydraulic cylinder applications. The presence of hydraulic seals is critical in all kinds of machinery. They are necessary in helping produce ways for fluid power to convert to linear motion. Hydraulic seals can be utilized for rotary and reciprocating motions.
Both hydraulic and pneumatic seals include your rod seals, piston seals and symmetrical seals. They also include wipers, rotary shaft seals, static seals, and oil and grease seals. And then there are the rings. There’s something called the V-ring. Then there’s also the O-ring. Amongst others, there’s your buffer rings, and your cast iron piston rings. Gaskets and u-cups too. Not D cups, u-cups. Seals for hydraulic purposes can act in motion in one axial direction.
But they can still be utilized for both directions to produce reciprocating motions, acting as double acting hydraulic seals. The seals are manufactured from a variety of materials. These include fluorocarbon rubber, bronze filled PTFE, glass filled PTFE, EPDM, nylon, nitrile, polyurethane and silicone. The seals can be molded from leather or fabric reinforced rubber. And that just about covers the material that serves as your worthwhile but brief introduction to the purposes of sealing mechanisms.
And in this case, the talk has been around sealing the hydraulics. Coherently answering the question; just what are seals doing in hydraulics, and for hydraulics will always be complex in the sense that its technologies and materials are being prepared for and implemented to a multitude of commercial or industrial processing and manufacturing and distribution areas.