Enormous force on an extremely small area

Piston Seals from Freudenberg Sealing Technologies stay in shape even under the greatest loads

Piston seals have the job of reliably sealing the piston against the cylinder tube while ensuring its efficient movement with minimal friction and without drift.

High functionality thanks to the right materials

Piston Seals from Freudenberg Sealing Technologies are used in a wide variety of state-of-the-art sealing systems. They are specially adapted to their particular tasks and conditions of use. Their high level of functionality is impressive.

State-of-the-art hydraulic Piston Seals can be precisely adjusted to a particular application with the selection of suitable materials. Polyurethane and PTFE materials mainly come into use. In combination with the Freudenberg Sealing Technology geometries – which have been proven a million times over – they always provide the optimal solution.

There are different ways to seal pistons in pneumatic cylinders (see illustration). In this case as well, the right products are available from the Freudenberg Sealing Technologies portfolio.

HDP 330: The piston seal for the harshest operating conditions

For applications with difficult operating conditions, the special polyamide (PA) HDP 330 piston seal from Freudenberg Sealing Technologies offers maximum functional reliability, while withstanding extreme pressures, as high as 800 bar. Thanks to the highly wear resistant sealing element material, cylinder tubes with rougher surfaces than would normally be recommended can be used for a simplified, cost-effective cylinder design.

Its extreme resistance to gap extrusion and its fast and easy installation are other advantages of this robust piston seal.

Another important feature of this two-component seal is its elastomer energizing element. It is generally produced from acrylic rubber (NBR), but a high temperature elastomer can also be used to achieve higher temperatures.

Our products in detail

FST Kolbendichtungen Piston Seals Dachmanschettensatz EK EKV Chevon Seal

Merkel Chevron Seal EK/EKV

Multi-element piston seal, consisting of thrust ring, a sleeve and a back-up ring. For robust areas of application, mainly for the supply of replacement parts for existing installations.

FST Kolbendichtungen Piston Seals Kompaktdichtung L27 Compact Seal

Merkel Compact Seal L 27

Multi-element piston seal for pistons that are pressurizable on both sides. Major gap bridging. Activated back rings offer significant protection against extrusion.

FST Kolbendichtungen Piston Seals Kompaktdichtung T42 Compact Seal

Merkel Compact Seal T 42

Multi-element piston seal for pistons that are pressurizable on both sides. Suited for use in mining (rams, advancing cylinders in progressive extension).

FST Kolbendichtungen Piston Seals Kompaktdichtung T44 Compact Seal

Merkel Compact Seal T 44

Multi-element piston seal for pistons that are pressurizable on both sides. Suited for maximum pressure loads in mining (rams, advancing cylinders in progressive extension).

FST Kolbendichtungen Piston Seals Nutring 0215 U-ring

Merkel U-ring 0215

Single-action, two-element piston seal for use in hydraulic and pneumatic applications. Fabric reinforcement on the running surface.

FST Kolbendichtungen Piston Seals Nutring 0217 U-ring 0217

Merkel U-ring 0217

Single-action, two-element piston seal for use in hydraulic and pneumatic applications. Shortened fabric reinforcement on the running surface.

FST Kolbendichtungen Piston Seals Nutring 0504 U-ring

Merkel Nutring 0504

Two-element piston seal with asymmetrical polyurethane profile ring and back ring. Among other purposes, usable as an individual seal in a pressure range up to 50 MPa and for the bridging of large seal gaps.

FST Kolbendichtungen Piston Seals Nutring TMP21 U-ring

Merkel Nutring TMP 21

Single-action piston seal made of abrasion-resistant polyurethane. For heavy pneumatic demands and high operating requirements.

FST Kolbendichtungen Piston Seals Omegat OMK-DR HB

Merkel Omegat OMK-DR HB

Merkel Omegat OMK-DR HB Three-element piston seal for combined lifting and turning movements. Protection against joint rotation in the event of turning movements, due to profile contact surface on the O-ring.

FST Kolbendichtungen Piston Seals Omegat OMK-ES

Merkel Omegat OMK-ES

Two-element piston seal for pistons that are pressurizable on one side. Especially suited to large diameters and suited to heavy-duty hydraulic applications.

FST Kolbendichtungen Piston Seals Omegat OMK-ES PR

Merkel Omegat OMK-ES PR

Two-element piston seal, consisting of one PTFE profile ring with pressure release function and skids as well as an elastomer profile ring as a pre-stress element. For heavy-duty, demanding applications.

FST Kolbendichtungen Piston Seals Omegat OMK-MR

Merkel Omegat OMK-MR

Two-element piston seal, consisting of a PTFE profile ring and an O-ring as a pre-stress element. For pistons that are pressurizable on two sides.

FST Kolbendichtungen Piston Seals Omegat OMK-QR

Merkel Omegat OMK-QR

Two-element piston seal, consisting of a PTFE profile ring and an elastomer profile ring as a pre-stress element. For pistons that are pressurizable on two sides, demanding applications and large diameters.

FST Kolbendichtungen Piston Seals Omegat OMK-S

Merkel Omegat OMK-S

Two-element piston seal, consisting of a PTFE profile ring and an elastomer profile ring as a pre-stress element. For heavy-duty hydraulic applications.