Hydraulic Cylinder Rod Seals & Pneumatic Rod Seals

The sealing of piston rods poses challenges that are difficult to resolve. To reliably retain the hydraulic fluid, the seal material must be relatively soft and resistant to abrasion, while at the same time, the material must have the hardness needed to prevent gap extrusion at high operating pressures and temperatures. Freudenberg Sealing Technologies combines these contradictory requirement profiles in a single component, the HDR-2C.

This rod seal consists of two high-performance polyurethane compounds with different hardnesses, which Freudenberg chemically combines into a single seal. This removes the need for a back ring and so facilitates easier installation.

The HDR-2C is thus the ideal solution for harsh operating conditions. It stays dynamically sealed under low and high pressure loads in a broad range of temperatures, from -50 to + 110°C. When compared to conventional one-component rod seals, extrusion gaps that are twice the normal allowable size are possible.

• The LF300 rod seal exhibits especially low friction in pressure applications with a range up to 160 bar.
• It is used for cylinder pressures of up to 320 bar and can withstand temperatures between -30°C and 110°C.
• A high degree of static and dynamic leak tightness is achieved due to its pierced seal edges.
• An asymmetric profile with a recessed interior lip is characteristic of its structure.
• The seal features a protected design with a grooved contact surface on its inner diameter, which enables jerk-free movement even at very low slide speeds.
• Along with its optimized stick-slip behavior, the product features an outstanding dynamic oil return feed.
• Its external diameter provides a tight, secure fit that is used as a primary and secondary seal in the rod seal systems at permissible slide speeds up to 0.6 m/sec (for primary seals) or 0.8 m/sec (for secondary seals).
• Highly wear-resistant polyurethane is used to create this amazing seal and it can be produced in a low temperature version that can withstand temperatures as low as -50°C.

• The T20 rod seal is available in standard sizes and is used for cylinder pressure up to 400 bar at temperatures between -30°C and 110°C
• This product can be delivered on short notice in dimensions between 8mm to 320mm.
• T20 seals have pierced edges that are used to achieve a high degree of static and dynamic leak tightness.
• The T20 is used as the primary seal for slide speeds up to 0.5m/sec.
• At speeds between 0.5 and 0.8m/sec, it functions superbly as a secondary seal in rod seal systems.
• The geometric design of the seal accommodates oil feedback into the pressure chamber.
• The T20 rod seal is manufactured using highly pressure-resistant polyurethane.
• Special versions, such as variations for a diameter range >320mm or low temperature applications as low as -50°C, are possible upon request.
• Given the totality of its positive characteristics, the T20 provides very good value for the cost.