Obtain news and background information about sealing technology, get in touch with innovative products – subscribe to the free e-mail newsletter.
Radial Shaft Seals
- Home
- Products
- Back to Dynamic Seals
- Radial Shaft Seals
Back to
Radial Shaft Seals: Precision in Motion
Radial shaft seals (also called oil seals, radial lip seals, or rotary lip seals) are critical components in mechanical systems, designed to prevent lubricant leakage and block contaminants from entering rotating assemblies. At the heart of this technology is the Simmerring® – a trusted name in sealing innovation. Developed through decades of engineering expertise, Simmerring radial shaft seals are used in millions of applications across industries, from gearboxes and pumps to electric motors and industrial machinery.
Each seal features a finely engineered lip that maintains contact with the rotating shaft, supported by a spring-loaded housing that ensures consistent pressure and sealing performance. This design not only protects internal components but also enhances system longevity and efficiency by reducing friction, heat generation, and oil degradation. In short, the right shaft seal choice improves reliability and lowers total cost of ownership.
Our rotary lip seals deliver consistent performance in high-speed and high-temperature environments. As a core type of shaft seal, these radial lip seals – often specified as oil seals in drawings – protect rotating equipment from ingress and lubricant loss.
Material Expertise That Drives Performance
Radial shaft seals are crafted from advanced proprietary materials that provide outstanding thermal resistance, robust wear durability, and minimal friction. Developed through extensive research and rigorous dynamic testing, these materials are designed to ensure compatibility with a wide variety of lubricants, shaft surfaces, and challenging operating conditions.
Whether it’s high-speed rotation, aggressive media, or extreme temperatures, our materials are formulated to meet the demands of modern powertrain and industrial applications. This material science foundation is what enables our radial shaft seals and oil seals to outperform in both standard and customized configurations.
Our oil seal compounds and PTFE-based radial lip seal designs minimize wear at the lip–shaft interface, maintaining stable contact pressure across varying speeds and temperatures.
Find a suitable Simmerring quickly with the Simmerring® Selector.
Radial Shaft Seals – Our Most Important Products Sorted by Application
Services / Added Value
Solutions that combine sealing with additional functionality to enhance system reliability and simplify assembly.
Lube & Seal:
Integrates sealing and lubrication in one unit, improving performance and extending warranty coverage.
Modular Seals and Combi Seals for Industrial Applications
These modular and combination seals offer flexible integration and multi-fluid compatibility for complex industrial systems.
MSS1 (Modular Sealing Solution 1):
Customizable elastomer-metal hybrid seal for modular powertrain configurations.
CASSETTE Seals:
Multi-lip seals with integrated dirt barriers, ideal for commercial vehicles, off-highway and heavy-duty environments.
COMBI Seal:
COMBI is a high-performance seal ideal for off-road axles, combining a duo-lip and polyurethane wiper for enhanced durability and dirt protection during axial movement and rotation.
CASCO® Seal:
Advanced cassette seal with axial lip and metal sleeve, delivering low friction and long service life in diesel and hybrid engines.
CTIS:
CTIS is a robust radial shaft seal designed for central tire inflation systems, enabling reliable pressure regulation in demanding off-road and on-road conditions.
Industrial Applications
These seals are engineered for demanding industrial environments, offering high performance in pressure, temperature, and chemical resistance. Across gearboxes, pumps, and electric motors, these oil seals and shaft seals are selected for reliability in contaminated environments and tolerance to misalignment.
Premium Sine Seal (PSS):
Features a sine wave lip geometry for reduced friction and enhanced sealing stability under dynamic conditions.
Premium Pressure Seal (PPS):
Built for hydraulic and pressurized systems, maintaining integrity under extreme pressure and temperature.
Gerromatic:
PTFE-based seal designed for chemically aggressive environments such as pumps and compressors.
Standard program BAUM:
A reliable and versatile sealing solution for general industrial applications.
Discover the new Technical Manual
Become a sealing expert! Our new edition offers an in-depth guide to materials and product expertise, offering a holistic view of sealing technology.
Read now!
Elevate Your Radial Shaft Sealing Systems with Precision Engineering
Discover precision engineering with Freudenberg Sealing Technologies. Our specialized Simmerring® engineering services go beyond selecting top-tier components. We analyze everything to unlock optimal sealing performance. Trust our expertise and commitment to excellence in sealing systems. Harness precision and innovation for peak performance.
Related Topics
Gearbox Innovations
Dive into this captivating on-demand webinar and explore the revolutionary world of Simmerring® seals.
Watch webinarRelated Products of the Dichtomatik Brand
Premium Freudenberg brand products meet the highest quality requirements and are suitable for all segments and applications. Complementing this, Dichtomatik brand products are a good solution for moderately demanding, non-safety-critical applications.
Dichtomatik Radial Shaft Seals open_in_new
-
E-Mobility
From the electrification of the power train to boosting charging speed, safety, and comfort, we can shape the technological change together.
Sealing Solutions for Drive Shafts in the Process Industry
Due to the many different and often unique features of the systems and processes in the pharmaceutical, food and chemical industries, a sealing system with drive shafts can be challenging.
-
Simmerring® BAUM RF – an Efficient Sealing Solution For High Speeds
The new Simmerring® BAUM RF (RF = Reduced Friction) is a targeted modification of the classic BAUM design and features a spring with reduced radial force. This adjustment minimizes friction at the sealing lip and reduces the thermal load on both the elastomer and the lubricant – particularly at high circumferential shaft speeds. The result: improved energy efficiency and an extended seal service life.
Simmerring® – the original oil seal
For more than 90 years, the traditional Freudenberg brand CFW® has represented innovation, high-quality and technical excellence of sealing technologies. Best proof is the original Simmerring®, a radial shaft seal developed by Walther Simmer at Freudenberg in 1932, branded CFW® ever since. The Simmerring® has gained worldwide recognition and is used in a wide range of applications.
Overview radial shaft seals
With the "easy to find" radial shaft seal poster, it only takes a second to pre-select the right seal for your application.
Premium Sine Seal (PSS)
Thanks to its unique design and sealing behavior, the Premium Sine Seal from Freudenberg Sealing Technologies can more than double the service life of the sealing system.
Spring-Energized PTFE Seals for Air Conditioning Compressors
Specialized spring-loaded PTFE (polytetrafluoroethylene) seal designed for dynamic scroll-type air conditioning compressor applications for sealing the seal plate to the fixed scroll. Seal design allows for high angles of misalignment without reducing sealing performance. Designed for easy assembly into the housing.
Simmerring® Radial Shaft Seal Standard program Design A/AS
The original Simmerring® is a premium quality radial shaft seal conforming to DIN 3760 and ISO 6194-1 with an elastomeric outer diameter. The Simmerring® can be used in numerous original equipment applications across a broad spectrum of market segments (e.g., gearboxes, transmissions, axles, engines, and pumps).
Simmerring® Standardization
Since 1929, the Simmerring® has stood for outstanding quality and today is known worldwide as a synonym for radial shaft seal rings.
Imperial Standard Range (ISR) Simmerring® Shaft Seals
The Freudenberg Sealing Technologies Imperial Standard Range (ISR) Simmerring® shaft seal is a premium quality seal typically used in applications such as gearboxes, axles, transmissions, and engines.
BABSL Classic Medium Pressure Seal
Medium pressure seals, such as the BABSL, can be used in many applications including pumps and motors in hydro-units, mechanical power transmission gearboxes, and 2-stroke engines.
Premium Pressure Seal (PPS)
Typically, with medium pressure seals, high friction and hollow wear occur due to pressure deformation at the elastomeric flex section of the seal—resulting in an enlarged contact band width.
BlueSeal
The BlueSeal is one design suited for future engine dynamic sealing. This patented radial shaft seal technology offers weight savings of 40 percent compared to a conventional seal, and it requires only half as much installation space.
Radial Shaft Energy Saving Seals, ESS™
Freudenberg Sealing Technologies radial shaft Energy Saving Seals (ESS™), demonstrate significant reduction of power loss in drive assemblies as opposed to standard sealing elements. By combining a special elastomer and a revolutionary new design, this shaft seal is able to maintain the pressure force at a consistently low level over a wide range of RPM, even at a higher sealing operating temperature. The low radial force of the main lip ensures the optimization of sealing function, abrasion resistance, and friction.
High/Low Pressure Seal (HLPS)
The High/Low Pressure Seal (HLPS) from Freudenberg Sealing Technologies is a field-proven, specialty-designed high pressure radial shaft seal. The HLPS is a severe duty pressure seal and has a unique design with several features that greatly improve its overall performance.
The Simmerring® Imperial Standard Range (ISR) Oil Seals
The Freudenberg Sealing Technologies Imperial Standard Range (ISR) Oil Seal is a premium quality seal typically used in applications such as gearboxes, axles, transmissions, and engines.
Low Friction Simmerring®
Values to the customer. ACM 380DF: better relaxation characteristics and bigger temperature range (–40°C to 175°C) compared to classic ACM. Lower friction compared to conventional sealing lip profile: 15 to 20%.
MileMaker
MileMaker is engineered for superior performance. The new MileMaker heavy duty wheel seals deliver significant energy savings and increase the reliability and durability performance expectations for wheel seals in the heavy duty truck and trailer industry.
POP® Seals
The Freudenberg Sealing Technologies PTFE POP Seal is designed for reduced friction in automotive drive assemblies as opposed to standard sealing elements.
Track Roller Seals
Freudenberg Sealing Technologies Track Roller Seals (Floating Seals) commonly used in heavy equipment and construction machinery are noted for their reliable seal endurance characteristics. These durable seals are resistant to moisture, natural contaminants such as sand and fiber, and harsh weather including radical temperature fluctuation, ozone, and extended UV radiation.
Cassette-S4 Seals
The Freudenberg CASSETTE-S4 is the most advanced Freudenberg solution for construction and agriculture mobile machinery wheel hubs and undercarriage applications.
Modification of Simmerrings
Simmerring® features – flexible & application-oriented The Freudenberg Sealing Technologies (FST) catalog program for Simmerrings covers a wide range of sealing applications and we make it possible to optimize existing Simmerrings from our extensive catalog range by making modifications to them.
The Simmerring® MSS 1
The MSS 1 Simmerring® is a unique, patented sealing system with proven functionality in different gearbox and pump applications and with a service life time up to 20,000 hours.
Related Documents
Related Videos
Join Us!
Experience Freudenberg Sealing Technologies, its products and service offerings in text and videos, network with colleagues and stakeholders, and make valuable business contacts.
Connect on LinkedIn! open_in_new
Back to Top