Rubber seals are some of the most versatile products out there, and navigating the vast array of seals available can be daunting on your own. To help you determine which rubber seal is right for your needs, refer to these rubber seal categories conveniently outlined below:

Silicone

Silicone is a material which demonstrates high resilience, temperature stability under extreme heat, and inertness. Silicone comes in several different forms, such as solid, sponge, and foam. Each of these forms has its own special advantages.

Silicone sponge has a closed cell structure, making it ideal for environmental sealing. It can be either soft (2-5 psi) or firm (in the 14-20 psi range).

Like silicone sponge, silicone foam has a closed cell structure and remains stable under UV light.
Other advantageous properties of silicone include being waterproof, flexible (protecting it from damage at extreme temperatures), and shrink-proof.

Neoprene

Neoprene is a type of synthetic rubber made of polymerized chloroprene, which forms a permanent seal. With resilience, tear-strength, and resistance to both UV and ozone damage, neoprene can be a very useful material as long as it avoids petroleum-based fuels. It has excellent resistance to temperatures as low as -40°F and as high as 250°F. Neoprene is also resistant to water and corrosion.

Urethanes

Urethane is a flexible, waterproof, and elastic material that also demonstrates aging and abrasion resistance. It is vulnerable to high temperatures, however. Urethanes come in a variety of blends and formulations.

EPDM

EPDM is a waterproof material with compressibility and aging properties which protect it from UV light, ozone, and oxidation. It comes in varying degrees of density. EPDM combines the closed structure of silicone with the wide temperature resistance of neoprene (from -60°F to 300°F).

This is just a sample of the many materials available at Real Seal. For more industry expertise, contact us today for all of your rubber seal questions and needs.

O-rings and other gaskets are most often used in static seal applications, meaning that the seal is attached and held firmly in place on a gland. Such applications are not damaged by friction or abrasion. If, however, the gland surface moves in relation to the seal, it is a dynamic seal that may require a lubricant to improve performance.

Dynamic applications have two additional factors to consider: break-out friction and running friction. Break-out friction refers to the force that initiates a seal’s movement, while running friction refers to the force needed to keep the seal in motion. Break-out friction can be up to three times greater than the force of running friction.

Choosing the Right Rubber Compound

Some compounds are better suited for dynamic applications than others. While nitrile and EPDM are suitable for dynamic applications, they do tend to have above-average break-out or running friction when used without lubrication.

Silicone and fluorosilicone have poor tensile strength, meaning that they rupture very easily. This makes them a poor choice for high-rate dynamic applications. Reserve these materials for low movement dynamic applications with smooth gland surfaces.

Fluorocarbon is significantly costlier than most other compounds, and cannot be used with steam. It does, however, have better temperature and chemical performance, as well as better running and break-out friction than most other elastomers.

Choosing a Rubber Seal Lubricant

Once you have chosen your material, an OEM engineering team will measure the friction on the seal. This will help you decide whether you need a lubricant to improve the efficiency or longevity of the seal.

External Lubricants

Hydrocarbon lubricants, as well as silicone and barium-based greases, can be applied to lubricants in-stock. These and powder-based lubricants (such as molybdenum disulfide and graphite) are often the best choice for initial reduction of friction. They are compatible with most elastomers and meet high temperature requirements. Additionally, they can provide extra protection from oxygen or ozone damage.
However, there are some negatives to consider as well. If the elastomer and the external lubricant are not chemically compatible, it may cause parts to stick together or otherwise impede assembly operations. Moreover, external lubricants may be lost through dilution into fluids which contact the seal, or through collection away from the seal.

Chlorination

Like external lubricants, chlorination can also be applied to stock O-rings. It is a permanent process which provides a smoother seal surface, reducing running friction. Though it has little effect on break-out friction, it can be used together with an external lubricant to great effect.

Internal Lubricants

Internal lubricants are friction-reducing agents like PTFE, graphite, and molybdenum disulfide, which are mixed into an elastomer. Due to the fact that an internal lubricant is chemically incompatible with the elastomer it is applied to, the elastomer will excrete the lubricant over time. Internal lubricants reduce friction, allow for more consistent performance, and have better assembly productivity in comparison to other lubricants. As with external lubricants, make sure that the internal lubricant is chemically compatible with the fluids it contacts.

Once your elastomer and lubricant are chosen, run the final tests to ensure optimal performance. To learn more or to purchase O-rings and lubricants, contact Real Seal today.

More often than not, the process of parts material selection and/or development can get fairly involved. To sum it all up it a nutshell, it’s similar to a game of pros vs cons where so many different variables come into play. In the case of TPE, the principle is no different. Factors such as meeting the performance requirements for a specific application, economic assessments, and processing issues, should all be reviewed in order to make the optimal choice. Looking at the qualities and considerations of this material can get this quest for the best off to a great start.

What is TPE?

Thermoplastic Elastomers, or TPEs, are flexible materials that exhibit the properties of rubber, but are processed like plastics. Suddenly when they first became available commercially in the 90’s, it was a whole new ballgame for the realm of engineering. TPE’s growth rate escalated as these high-performance materials continued to be used in a plethora of applications. However, just like with other materials, TPE’s scorecard comes with its share of benefits, as well as a few setbacks penciled in.

The Good, the Bad, & the Comparison

Because TPE is processed like plastics, the process is simplified and tends to produce increasing advantages. Due to the need for fewer steps, such as little to no mixing/blending required, TPE can be lead to lower costs and therefore, increased economic advantages. Not to mention, when compared to traditional thermoset rubber, TPE typically also offers:

• Shorter fabrication /cycle time
• No finishing or post cure required
• Lower rate of energy consumption
• Recyclable parts, can be used as “filler” in many applications
• Lower density that can lead to lower part costs

Although these features can make TPE very beneficial, there are some drawbacks to explore. One being, that the tooling to produce these materials can be expensive, especially if the geometrical design of the part is complex. Also, even though TPE materials over the years, they still haven’t caught up to rubber in terms of their physical properties. When comparing the two, rubber has superior tensile strength, compression set, and elongation capability.

Real Support for Real Solutions

Undoubtedly, there’s plenty of things to consider when selecting a material. But it doesn’t stop there. Even when that’s been covered, other factors exist that can possibly influence processing and impact costs. At Real Seal, we offer engineering and design support to assist customers in their quest for the best and a real solution to their elastomeric product needs. Please contact us if you are interested in support for your engineering application, or call us at 800-542-6162 today.

Original equipment manufacturers, or OEMs, commonly have to deal with a multitude of factors and challenges. Due to the fact that the realm of engineering has become more specialized, these challenges can come at them from different angles. Many times, in order for OEM’s to stay at the forefront of technological advances, reduce engineering costs, or tackle aspects of product performance and function, they obtain some help from suppliers in the form of engineering and design support.

Creating Solutions, Achieving Results

Engineering and design support can be a fairly broad domain, and at Real Seal we cover this line of support in 4 main areas. First, is the area of Materials Engineering. Staffed with a polymer chemist, our facility has developed materials that are designed to work for specific applications and meet various criterion, such as environmental regulations and performance factors. Examples of our recently developed material options includes an EPDM rubber material with an improved tear strength and a HNBR material that is more cost effective. These enhanced material choices are available through us with not only the benefit of relevantly small cost, but usuallywe can also develop them significantly much faster than large manufacturers can.

Now onto the cutting edge territory of Design Engineering. Understanding that unique materials like rubber and plastics have the capability to act differently than expected, our facility can be instrumental in the design process by making recommendations that can have a big impact on OEM products. With innovative CAD 3D software, we create a virtual model of the specific application and underline the dynamics of it when in use. Based on those indications and our expert analyzation, many products have resulted in an overall improvement in their efficiency and endurance.

When dealing with the intricacy of tool design, things can get complex. The area of Design for Tooling offers valuable support in which the aspects of tooling, such as gate locations and parting lines, are reviewed and modified. In effect, these adjustments have the potential to save hundreds to thousands of dollars in tooling/fabrication costs that can amount to long-term savings.

The final main area of engineering and design support is Design for Assembly. Here, we review the product assembly process, consider the potential issues or problems, and then make suggestions based upon the findings. These problems may include improper part positioning, or left hand and right hand design variants. In any case, we use our knowledge and resources to recommend alterations that can have a big influence on assembly effectiveness and possibly expenses.

Offering Superior Support

Through Real Seal’s engineering and design support, many OEM’s have been able to solve specific problems presented to them, and achieve results that have benefited both their products and their bottom line. If you are interested in the possible solutions that can be discovered for your project, contact our experienced team of engineers today.