Tag Archives: specialty seals

EPDM vs. Nitrile Rubber: What’s the Difference?

Posted on by

The right rubber material is essential for applications involving specialty seals, gaskets, hoses, cables, and other components. EPDM and nitrile rubber (NBR) are two widely used synthetic elastomers. EPDM vs. Nitrile Rubber: What’s the Difference? This is an important question for manufacturers and engineers because they excel in very different properties. Understanding the differences between these materials is essential because it helps manufacturers and engineers choose the right material for an application’s operating conditions.

EPDM vs. Nitrile Rubber: What’s the Difference?

EPDM stands for ethylene propylene diene monomer. It is a synthetic rubber widely recognized for its excellent resistance to weathering, ozone, UV exposure, water, and steam. Because of these properties, EPDM is particularly well-suited to outdoor and environmental sealing applications.

EPDM is commonly used for weatherstripping, roofing materials, HVAC seals, automotive coolant hoses, water system components, and outdoor gaskets, and it generally maintains flexibility over a relatively broad temperature range. However, exact temperature limits depend on the specific compound and formulation.

EPDM’s ability to withstand prolonged exposure to ozone and sunlight is one of its biggest advantages. It can also perform well in hot water, and sometimes in steam, depending on the compound and service conditions. However, even with all its advantages, EPDM is not perfect. It has a major limitation. It is generally not suitable for petroleum-based oils, fuels, or many hydrocarbon solvents. When exposed to these substances, rubber can swell, soften, or lose its mechanical properties.

What Is Nitrile Rubber?

Nitrile rubber, also known as NBR or Buna-N, is a synthetic elastomer made primarily from acrylonitrile and butadiene. It is famous for its strong resistance to petroleum-based oils, fuels, greases, and many hydraulic fluids. Because of this, nitrile is commonly used in oil seals, O-rings, fuel system components, hydraulic seals, industrial hoses, and machinery parts that contact petroleum-based fluids.

Nitrile is also well-suited to demanding industrial environments because it offers strong mechanical properties and abrasion resistance.

However, nitrile has a weaker resistance to ozone, UV radiation, and long-term outdoor weathering than EPDM. In addition, it is also generally less suitable for steam service. Because of this, an NBR component that works well inside an oil-based system may deteriorate faster with continuous exposure to sunlight, ozone, and outdoor conditions.

The Main Differences Between EPDM and Nitrile

The biggest difference between the two is their resistance to different types of exposure.

EPDM is generally the better solution for:

  • Outdoor environments
  • Ozone and UV exposure
  • Weathering
  • Water and many water-based applications
  • Hot-water applications
  • Selected steam applications, depending on the compound
  • Automotive coolant and glycol-based systems

Nitrile is generally the better choice for:

  • Petroleum-based oils
  • Fuels
  • Greases
  • Mineral-oil-based hydraulic fluids
  • Oil seals and fuel-system components
  • Applications requiring good abrasion resistance

EPDM is designed to handle the weather, while nitrile is designed to handle oil. Ensure you don’t use one material in an environment suited to the other, as this can significantly shorten the component’s service life.

What About Temperature Resistance?

While both materials can perform across useful temperature ranges, the exact limits vary considerably by compound, curing system, hardness, and application. EPDM is generally valued for its broad temperature capability and strong aging resistance in air, water, and outdoor environments. In comparison, nitrile works well at moderate temperatures, particularly when used with compatible oils and fuels. 

Don’t choose either material based solely on a general temperature range.

Which Rubber Should You Choose?

When choosing a rubber, start by considering the application’s operating environment. If the component is expected to be exposed to sunlight, ozone, rain, water, or outdoor weather, EPDM is usually the better choice. If petroleum-based oil, fuel, grease, or compatible hydraulic fluid is the main concern, nitrile is the better option.

Also consider any substances the rubber may encounter, such as occasional oil mist, cleaning chemicals, lubricants, or other additives. Even limited exposure to an incompatible chemical can affect rubber performance over time.

Get the Right Sealing Solution

EPDM and nitrile rubber are not interchangeable materials. Each offers advantages in the right environment. If you are looking for reliable specialty seals, talk to us today so we can help you find the right material and sealing solution.

Top Causes of O-Ring Failure

Posted on by

O-rings and specialty seals may be small, but the role they play in keeping machinery, hydraulic systems, plumbing equipment, and other industrial applications running as they should is massive. These circular seals are designed to prevent leaks between two connected parts. They help maintain pressure and protect equipment from contamination. When O-rings fail, the consequences can be costly downtime, safety hazards, fluid loss, and equipment damage.

Understanding the common causes of O-ring failure is essential for preventing leaks and extending the lifespan of your systems. Here are the top causes of O-ring failure and the practical ways to avoid them.

Top Causes of O-Ring Failure and How to Prevent Leaks

Incorrect Material Selection

    The wrong material for an application is problematic, as it is one of the most common causes of O-ring failure. Different environments expose seals to varying temperatures, chemicals, pressures, and fluids. With incompatible materials, O-rings may swell, crack, harden, or deteriorate over time.

    For instance, O-rings that perform well in water applications may quickly fail when exposed to aggressive chemicals or petroleum-based fluids.

    How to Prevent It:

    Always choose an O-ring material specifically designed for the operating environment. Consider factors such as:

    • Temperature range
    • Chemical compatibility
    • Pressure levels
    • Exposure to UV or ozone
    • Type of fluid or gas involved

    Popular materials include nitrile, Viton, EPDM, and silicone, each with different strengths and limitations.

    Excessive Heat or Temperature Extremes

      Extreme temperatures can damage O-rings. The material can harden, lose elasticity, or crack at high temperatures. On the contrary, when the temperature is too low, the seal can become brittle and unable to maintain compression.

      O-rings that are no longer flexible cannot create an effective seal. This leads to leaks and equipment failure.

      How to Prevent It

      Use temperature-resistant materials that are appropriate for your operating conditions. Materials such as Viton or silicone are often better choices in high-temperature environments. Regular inspections are important because heat-related damage can develop gradually.

      Improper Installation

        Even the best O-rings fail if not properly installed. Twisting, overstretching, pinching, or cutting during installation can create weak points that eventually lead to leakage. The problem is, installation damage is not immediately visible. This means that most people realize there is a problem only when the seal fails during operation.

        How to Prevent It

        Ensure that Installation procedures are followed.

        • Lubricate the O-ring before the installation
        • Use the correct installation tools
        • Avoid sharp edges and rough surfaces
        • Ensure the groove dimensions are accurate

        Compression Set

          A compression set occurs when an O-ring remains compressed for an extended period and loses its ability to go back to its original shape. The seal will no longer maintain adequate pressure against the mating surfaces once it has lost its elasticity.

          How to Prevent It

          Choose materials with strong compression-set resistance, and ensure the seal is not exposed to excessive heat for extended periods. To prevent unexpected failures, replace O-rings in critical systems periodically.

          Chemical Degradation

            Some chemicals can attack O-rings, causing swelling, softening, or cracking. Chemical degradation weakens seals and reduces their ability to prevent leaks.

            How to Prevent It

            Remember to verify chemical compatibility before selecting an O-ring material. Manufacturers usually provide compatibility charts. This helps determine which materials work best with specific chemicals and fluids.

            Schedule routine inspections for seals that operate in harsh chemical environments.

            Abrasion and Water

              O-rings in dynamic applications experience repeated movement, friction, and pressure changes. Over time, consistent motion can cause scratches, tears, or surface flattening on the seals.

              How to Prevent It

              Use proper lubrication and choose wear-resistant materials to reduce friction. Remember that smooth surface finishes and proper equipment alignment can also minimize abrasion. If high-speed movement or heavy pressure is involved in the application, use backup rings for additional support.

              Pressure Damage and Extrusion

                Excessive pressure can cause small gaps between components. This can cause extrusion or tearing. A damaged seal will no longer maintain pressure effectively.

                How to Prevent It

                Make sure you use O-rings designed for the system’s pressure requirements. Use backup rings in high-pressure environments. Remember to maintain recommended pressure limits.

                Find the Right Sealing Solutions Today

                Looking to improve the reliability of your equipment and reduce costly leaks? Choose specialty seals that are engineered to perform in demanding environments and support effective O-ring failure prevention across a wide range of industrial applications. Contact us today, and we will help you keep your operations running smoothly with the right sealing solutions for your system.

                Mechanical Applications of Automotive Seals

                Posted on by

                Automotive seals, as the name implies, are used in vehicles. They are devices that are used to join systems together. It also prevents leakage, exclude contaminants, and contain pressure. There are different types of seals and they are used in induction sealing, heating, stuffing, and adhesion of parts. The efficacy of the seals is dependent on the adhesion of both the sealant and the gasket.

                Functions of Automotive Seals

                Unlike other seals used in different industries, automotive seals have excellent reliability, are long-lasting and extremely silent. They can survive heavy duty use and extreme vibrations attributed to a running engine. Without these seals, everything would fall apart. Seals allow the vehicle to function properly as well as to run. They are used in different applications not only in cars but also in motorcycles, ATVs, and off-road heavy machinery and equipment.

                Seals are integral parts of the automotive industry. They are used in a variety of different applications. Seals may be small but they serve an even bigger and greater purpose in the integrity of the vehicle. Below are the functions of the seals in cars.

                • They enclose the gas and liquid within the chamber. The gas tank contains seals that allow the vehicle to use up the fuel without wasting it. Hydraulic seals are also important for the movement of vehicle parts. Systems within the vehicle that uses hydraulic seals include suspensions and brakes.

                • Stave off contaminants from crucial parts of the vehicle components. Seals keep away dust and other debris away from the engine and other important components of the vehicle.

                • They keep liquids and gases separated from one another. There are many car parts that use liquids and gases to function properly. Examples include: the engine which keeps the coolant and engine oil, brakes for the brake fluid, and the reservoir to keep the power steering fluid to name a few.

                • To protect bearings. Bearings are often filled with lubricants that protect the parts from corrosion, wear, and tear. The bearings need to be spotless, thus a contamination within it may cause the housing elements to experience premature failure. The seals protect the bearing by preventing dust and powder from entering the assembly.

                Types of Automotive Seals

                There are a lot of seals that the automotive industry use but there are two types of seals that are commonly used. These seals have also found their way into other industries. Below are the different types of automotive seals that also have mechanical applications.

                O-rings seals

                O-rings are made from elastomeric materials. They function by sealing two adjacent surfaces thus keeping the liquids contained from within a particular system. They are designed to take on extreme pressure and temperature as well as corrosive gases and liquids. They are designed to have a contact with the sealing face. It is very flexible. Thus, allowing it to accommodate any imperfections on the mounting surfaces.

                It is considered as one of the most common type of seals used in machines as they are cheap and very easy to manufacture. They are also very reliable and have simple requirements, making the mounting process less complicated. Also called toric joint or packing, O-rings also have mechanical applications especially where relative motion between parts are involves. They are used to contain pressure and fluid. O-rings are used in vacuum applications to keep the pressure in check. They are also used to prevent leaks in pumps.

                Lathe-cut seals

                Lathe cut seals are used similarly with O-rings. They are made from a rubber tubing that has been inserted with a mandrel to cut the desired dimension. They provide more cost-performance benefits especially when static seal is needed. Unlike O-rings, lathe-cut seals provide wider surface for sealing thus making it more resistant against compression. They are also less expensive making them great for high volume gaskets.

                Lip seals

                This type of seal is used in rotating shafts. The lip provides a seal from a low-pressure chamber. It is installed in the pressure source and it balloons out to provide tight sealing. They are used in motors as well as reversible motors. They are also used in devices that need to maintain vacuum conditions to preclude dirt and contamination for entering.

                Packing

                Packing is a type of woven fiber that are packed between parts that needed to be sealed. This type of packing can be dynamic or static. It functions as a rotating shaft seal and gasket in different types of application. It is placed in a bore and compressed by a flange in automotive parts. It can also be used to seal a pump. In fact, industries like the paper manufacturing and milling use packing seals to prevent leaks.

                Seals are created to prevent leaks. There are different types of leaks that are used in different industries but it is important to take note that even if they are designed to cater to the automotive industry, they have profound mechanical applications.

                For more information on a variety of engineered rubber and plastic sealants, machinery devices, laboratory testing, and design engineering, contact Real Seal.

                Our organization is geared to meet the more fragmenting aspects of industry today. Industrial manufacturers are being tasked with offering consumers more choice, a wider latitude of performance criterion, and greater economic restraints. As American industry continues to evolve to meet the demands of today’s consumers and the challenges of international competition, Real Seal continues to provide solutions and create value.