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Dynamic Seals

Dynamic seals are used in applications with motion between the hardware component and the sealing solution. The motion can be rotary, translatory, reciprocating or oscillating. Effective dynamic seals need to maintain a balance between the sealing force, minimize the friction and furthermore prevent leakage.

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Rod Seals From Freudenberg Sealing Technologies Perform Multiple Tasks

Rod Seals are primarily used in pneumatic and hydraulic cylinders and have the task of sealing the incoming and outgoing cylinder rod. The goal is to prevent the escape of the pressurized operating medium from the cylinder. At the same time, it must be protected against external contaminants. Freudenberg Sealing Technologies offers the right Rod Seal for every kind of cylinder and application.

Maximum Efficiency From the Best Possible Combination

Rod Seals from Freudenberg Sealing Technologies are used in state-of-the-art sealing systems for cylinders of all kinds. They are specially adapted to the respective conditions of use and tasks while meeting customers’ high expectations for maximum reliability, service life and functionality. State-of-the-art hydraulic rod sealing systems generally consist of several individual seals (see example in Fig. 1). The so-called primary seal faces the cylinder’s working space and reliably seals against the high operating pressure within the cylinder.

The secondary Rod Seal fitted behind it takes over the main sealing function. It is above all designed to reduce the residual oil film on the rod to a minimum during its extension. Seals constructed of polyurethane are preferably used for this task. With their defined sealing lip, they ensure the finely tuned wiping of the medium, guaranteeing the leak tightness of the cylinder toward the exterior.

So-called wipers are used as a third element in the rod sealing system, in addition to the guide elements that prevent the contact of the incoming and outgoing rod with the housing. Their task is to protect the systems’s primary and secondary seals from external contamination and influences. In addition, Static Seals are needed for the cover/cylinder housing intersection.

Freudenberg Sealing Technologies has continued to develop its rod sealing systems and to equip them with additional functions. For example, in addition to storage modules to take in drag oil, pressure discharge functions are used when special requirements arise, including long strokes or great differences in a rod’s incoming and outgoing speed. They effectively prevent an excessive system-related buildup of pressure within the sealing system and protect against the premature failure of the primary and secondary seals.

State-of-the-art pneumatic rod sealing systems use combined wiping/sealing elements as their operating pressures are lower than those of hydraulic systems. In combination with special materials, these sealing systems are high-performing and an outstanding value for the money.

Whatever the conditions, sealing systems from Freudenberg Sealing Technologies stand for excellent long-term performance.

Our Products in Detail

FST Stangendichtungen Rod Seals Merkel Dachmanschettensatz Chevron seal set DMS-0180

Merkel Chevron Seal Set DMS-0180

Multi-piece rod seal, consisting of a polyethylene thrust ring, polyethylene sleeves and an elastomer back-up ring. Suited to harsh operating conditions and ceramic counter surfaces.

FST Stangendichtungen Rod Seals Merkel Dachmanschettensatz Chevron seal set ES 61

Merkel Chevron Seal Set ES61

Multi-piece rod seal, consisting of a thrust ring made of a PTFE-bronze compound, fabric sleeves and a rubber-sprung backup ring. For harsh operating conditions and large seal gaps.

FST Stangendichtungen Rod Seals Merkel Dachmanschettensatz Chevron seal set ES-81

Merkel Chevron Seal Set ES81

Multi-piece rod seal made of a rilled thrust ring made of polyurethane, fabric sleeves and a rubber-sprung back-up ring. Suited to existing designs and short-term underpressure.

FST Stangendichtungen Rod Seals Merkel Dachmanschettensatz Chevron seal set ES ESV

Merkel Chevron Seal Set ES/ESV

Steering seals for rotational and reciprocating applications including hydraulic pump and valve seals and dust seals for electric steering systems.

FST Stangendichtungen Rod Seals Merkel Kompaktdcihtung Compact Seal 58

Merkel Compact Seal S8

Single-piece rod seal with an elastomer head set in the fabric part for light and medium requirements.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring 0214

Merkel U-ring 0214

Single-acting, two-piece rod seal suited for use in hydraulic and pneumatic applications. With fabric reinforcement on the running surface.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring 0216

Merkel U-ring 0216

Single-acting, two-piece rod seal suited for use in hydraulic and pneumatic applications. Shortened fabric reinforcement on the running surface.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring 0503

Merkel U-ring 0503

Two-piece rod seal with asymmetric polyurethane profile ring and back-up ring. Among other purposes, usable as a single seal in pressures up to 50 MPa and for bridging major seal gaps.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring L 20

Merkel U-ring L20

One-piece rod seal with asymmetrical elastomer U-ring and shortened interior lip. Preferably to be used as a secondary seal in a seal system with water and water emulsion operating media.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring NRSF 8009

Merkel U-ring NRSF-8009

Special single-acting U-ring for sealing severely soiled slewing bearings with a press-fit at the outer diameter. For pivoting motions or slow rotating movements at low to medium pressures.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring T 20

Merkel U-ring T20

Tried-and-tested, one-piece rod seal for use as secondary seal in a seal system or as a single seal in pressures up to 40 MPa, among other purposes.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring TM 20

Merkel U-ring TM20

Turned version of the Merkel T 20 rod seal with a press-fit at the outer diameter. Among other purposes, suited for use as a secondary seal in a sealing system or as a single seal for pressures up to 40 MPa.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring TM 23

Merkel U-ring TM23

Two-piece rod seal with a polyurethane profile ring and a backup ring. Especially designed for the sealing of piston rods in rams, advancing cylinders, and secondary cylinders in progressive extension.

FST Stangendichtungen Rod Seals Merkel Nutring U-ring TMP 20

Merkel U-ring TMP20

Single-acting rod seal made of abrasion-resistant polyurethane. For heavy-duty, pneumatic demands and high operating requirements.

FST Stangendichtungen Rod Seals Merkel Omegat OMS-DR HB

Merkel Omegat OMS-DR HB

Two-piece rod seal, consisting of a PTFE profile ring with retaining flange to secure against co-rotation and an O-ring as a pre-tensioning element. Suited for rotary and swivel movements.

FST Stangendichtungen Rod Seals Merkel Omegat OMS-MR

Merkel Omegat OMS-MR

Two-piece rod seal, consisting of a PTFE profile ring as well as an O-ring as a pre-tensioning element. Among other purposes, for use as the primary seal in a sealing system.

FST Stangendichtungen Rod Seals Merkel Omegat OMS-MR PR

Merkel Omegat OMS-MR PR

Two-piece rod seal, consisting of a PTFE profile ring with a pressure relief function as well as an O-ring as a pre-tensioning element. For use as the primary seal for long strokes or major speed differences in the incoming and outgoing rod.

FST Stangendichtungen Rod Seals Merkel Omegat OMS-S

Merkel Omegat OMS-S

Two-piece rod seal, consisting of a PTFE profile ring and an elastomer profile ring as a pre-tensioning element. Especially for large diameters and heavy hydraulic applications.

FST Stangendichtungen Rod Seals Merkel Omegat OMS-S PR

Merkel Omegat OMS-S PR

Two-piece rod seal, consisting of a PTFE profile ring with a pressure relief function and a support runner as well as an elastomer profile ring as a pre-tensioning element. For use in heavy hydraulic applications as a primary seal for long strokes and major speed differences in the incoming and outgoing rod.

FST Stangendichtungen Rod Seals Merkel Omegat OMS-S SR

Merkel Omegat OMS-S SR

Two-piece rod seal, consisting of a profile ring made of PTFE or PE, a support runner, and an elastomer profile ring as a pre-tensioning element. Usable a single seal in combination with a double wiper. For short strokes up to 10 mm.

FST Stangendichtungen Rod Seals Merkel Omegat OMSU-MR PR

Merkel Omegat OMSU-MR PR

Two-piece rod seal, consisting of a polyurethane profile ring with a pressure relief function and an O-ring as a pre-tensioning element. Usable as a single seal in combination with a double wiper.

FST Stangendichtungen Rod Seals Merkel Syprim SM

Merkel Syprim SM

Two-piece primary rod seal that is basically used within a seal system in combination with a U-ring (e.g. Merkel U-ring T 20).

FST Stangendichtungen Rod Seals Merkel V-Pack Seal V-packing set V 1000

Merkel V-Packing Set V1000

For the sealing of piston rods and plungers – in special cases for pistons as well. Thanks to its robust design, it is extremely well suited to highly demanding, heavy and even lying presses.

Related Documents

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