Profiles
Wiper
Guide Rings
Rod Seal
O-rings
Piston Seal
Rotary Seal
Symmetric Seal
Mining Seals
Wiper
Sealing elements intended for prevention of solid particles from entering a hydraulic or lubrication system are referred to as wipers or dirt scrapers. There are also scrapers used for preventing liquids from penetrating and sometimes both tasks have to be fulfilled simultaneously. There is usually no hydraulic pressure applied to a scraper. It is imperative to have the scraper in a stable position in the groove, which can be improved by additional axial or radial support
Rod Seal
Due to their importance in a hydraulic cylinder, rod seals should be mentioned first. A leak at this important point would lead to serious influences on the operating system and would cause damage to the environment. The rod seal must have a tight fit and make a perfect seal when in motion and motionless. For this reason, some types of seals include pre-loading elements (usually made out of NBR) to ensure a tight fit and seal even in a motionless or depressurized state. At higher operating pressures, additional support rings are used on the rod seal in order to avoid losing the seal.
Piston Seal
A single-acting piston seal operates in the same way like a rod seal, but with the difference that the dynamic sealing lip of a piston seal is located on the outside. Double acting piston seals are designed symmetrically as they are pressurized from both sides. Even piston seals are sometimes equipped with pre-loading elements in order to create an even tighter seal. At higher operating pressures, additional support rings are used in order to avoid seal extrusion.
Symmetric Seal
Symmetrical seals can be used both as a piston and rod seal due to their geometry. They are, so to speak, a universal solution without a specific design of the sealing lip.
Guide Rings
Guide rings are used to guide pistons and piston rods. This is necessary to avoid contact of metallic surfaces that are moving close to each other. Guide rings are usually cut at an angle in order to deliver sufficient hydraulic oil between both metal surfaces.
O-rings
O-rings are mainly used as static seals, but can get used for dynamic applications as well. Due to their geometry, they may be used as double-acting.
Rotary Seal
Rotary seals are generally classified for applications under pressure, and for pressure-less applications.
Mining Seals
Mining seals usually are multi-part seals with additional back-up rings and preloading elements in order to meet the increased requirements.
Pertaining to their geometry these seal types resemble the usual piston- and rod seals, but they got adapted to the comparatively high hydraulic pressure of mining applications.
