Back-up rings are anti-extrusion elements designed to prevent the migration of sealing material into the extrusion gap under the system pressure. They are open or closed shapes for snap assembly made of a broad range of compounds which are highly resistant to thermal or mechanical stress.
In pneumatic cylinders, cushioning seals are part of a design that provides for controlled final position retardation. Up on approaching the final position, a tapered sleeve, firmly located on the piston rod, progressively closes off the open passage toward the line connection of the cylinder. In this phase of motion, the defluent medium is led via a, usually adjustable, needle valve, the adjustment of which controls the degree of stroke movement retardation. During reverse operation, the cushioning seal designs provide a non-return valve functionality and ensure free flow.
Custom seals are individual and exclusive designs for a specific application profile.
Fastener seals are composite sealing washers, consisting of a metallic
carrier and a vulcanised elastomer sealing lip. They provide a static sealing function on flanges or threaded connections. They consistently assure ideal compression
conditions between the housing components and thus prevent the destruction of the sealing lip.
Flange seals provide the front-face static sealing function within flange connections. There are two major design principles available, either for internal or external pressure. Various designs in a broad range of compounds provide individual features.
Guiding elements provide the bearing function between the metallic components of the unit during the stroke movement and in static conditions. They prevent metallic contact between pistons and cylinders or rods and glands where forces act perpendicular to the direction of movement.
Rod and buffer seals for fluidpower cylinders and actuators seal the applied system pressure against the atmosphere side. Rod seals have a sensible functionality, because if leakage occures externally, it may contaminate the ambient environment. They are available as single-acting and double-acting seals, however preferably used as single-acting seals. A wide range of compound and profile configurations is available to meet the user´s specific application profile. They usually interact with wiper elements in the cylinder head sealing system.
Rotary seals separate system pressures and media against the atmosphere under rotating movements of the opposing surface. There are two generic categories of rotary seals: high-pressure/low-velocity (rotor seals) and low-pressure/high-velocity (rotary shaft seals). Both symmetrical and unsymmetrical designs are available.
Static seals provide the sealing function in all applications in which no movement of the sealing element versus the sealing surface relative to one another occurs.
Valve seals are dynamic piston or rod seals which perform sealing functionality on valve spools. The designs are usually extremely slim and small in diameter due to the valve requirements. The designs are usually individual and exlusive to a specific application profile.
Wipers are designed to prevent any contamination of the system by external particles or other environmental impacts during translatoric movements in cylinders and actuators. They also provide the static sealing function on the cylinder head versus the atmosphere. Some double-acting designs also reduce the drag oil film during outstroke.
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