Proper Material Choices Essential to Application Success
There are countless material compounds available for use in sealing applications. But when you need near-universal chemical and thermal performance, perfluoroelastomer seals have proven to be in a class of their own.
If you want to learn more, please visit our website.
Perfluoroelastomer compounds, also known as FFKM for short, are elastomeric forms of polytetrafluoroethylene (PTFE) — itself a versatile and popular material. Due to a fluorinated backbone (and higher fluorine content over fluoroelastomer or FKM compounds), perfluoroelastomers gain additional elasticity, which helps earn usage in a number of demanding applications.
The world has taken note. With a projected compound annual growth rate of 2.4%, the world market for FFKM is expected to grow from $377.3 million to $446.3 million in the next five years. The material’s unique characteristics make it a favorite in chemical processing industry (CPI) applications, particularly in North America, and it’s this market that is expected to be a major driver in that projected growth.
Why Choose Perfluoroelastomer Seals?
Let’s take a look at why this premium material is experiencing a growing demand. FFKM compounds are valued for their ability to handle the harshest conditions and most demanding environments. If you need strong chemical compatibility attributes, thermal resistance in high (or low) temperature environments — or both — perfluoroelastomers provide the best coverage available. Combined with versatility and durability, these have made FFKM compounds a go-to choice across many industries.
Here’s a breakdown of those aforementioned strengths.
Chemical Resistance
Perfluoroelastomers are the most chemically resistant elastomers available and — depending on the specific formulation — can provide strong resistance to a specific element or a broad array of potential chemicals. For example, FFKM can resist more than 1,800 different chemicals, including hydrocarbons, oils, and fuels. Additionally, a perfluoroelastomer o-ring will have high resistance to steam, various solvents, ozone, and weathering.
Because of all this, FFKM has become the desired material for many CPI applications and has been tested and proven to be the best choice when engineering sealing solutions for applications dealing with steam environments.
Thermal Stability
No other compound can offer the protection for extended periods and at the highest temperatures that FFKM provides. While the ranges vary depending on the specific formulation used, perfluoroelastomer compounds can be used to provide thermal resistance to temperatures ranging from 335 degrees Celsius (635 Fahrenheit) at the upper end of the spectrum, to -46 C (-51 F) on the colder end.
Seals operating in lower temperatures will suffer a loss in flexibility; those working in high temperatures will see material alterations, potentially leading to issues like gas absorption and rapid decompression. But by using FFKM compounds, designed and formulated for those extreme conditions, you can ensure greater stability, performance, and dependability as the materials will better adhere to their original properties.
Versatility and Reliability
PTFE itself, one of the building blocks of FFKM compounds, lends beneficial attributes as well. PTFE is known for its high flexural strength, even in low temperatures, and provides a low coefficient of friction. This means perfluoroelastomer compounds will also have excellent mechanical wear-and-tear resistance or resilience. Combined with the chemical resistance and thermal stability characteristics, FFKM compounds will give the most durability and performance in the most demanding applications. This will help avoid failures and downtime, which save money in operating costs and alleviate dangerous risks to workers, equipment, and the environment.
All of these characteristics have helped make FFKM the preferred choice for essential seals in a host of industries, including (but not limited to):
- Automotive and Aerospace
- Oil and gas exploration
- Paint and Ink production
- Water and Irrigation
- Food manufacturing and processing
- Medical and life science
We Are Your Perfluoroelastomer Experts
For more than 40 years, Marco Rubber & Plastics has collaborated with those facing demanding applications to execute engineer-assisted custom sealing solutions. Our experience has given us the expertise to help you find or formulate the ideal solution no matter the circumstances.
With access to more than one billion sealing solutions throughout our expansive production network, we offer a wide range of FFKM materials and compounds, including major brands such as DuPont’s Kalrez® and Greene Tweed’s Chemraz® with a wide selection of specific formulations as well.
In addition, we also offer our own proprietary FFKM material — Markez® — which delivers the same high-temperature, chemically-resistant performance that is on par with any other brand but comes with greater availability and shorter lead times.
You will get efficient and thoughtful service from NFJ.
Ultimately, the performance of a perfluoroelastomer o-ring or seal will depend on how it matches the application itself, as the material formulations can vary widely. It’s important to discuss all aspects of your application with an application engineer to find and consider all the right potential solutions. With more than 14,000 repeat customers worldwide, Marco Rubber has proven it can be counted on to find the ideal match between application and sealing solution.
Seal Your Success with Perfluoroelastomer O-Rings from Marco Rubber & Plastics
Speak to an Expert | Buy O-Rings Online | Request a Custom Quote
The utilization of elastomers is extremely common in our modern environment. Elastomers are used in a variety of applications, including sealing fluid applications, tires, chemical plants, semiconductor manufacturing equipment, dust and moisture seals on cell phones, and aircraft engine seals, among others. Elastomer applications can range from something as simple as a rainwater barrier to more complex applications like essential sealing applications on the International Space Station (ISS). Even though there are many different elastomers available on the market today, there was a time when material scientists needed to develop something new to meet increasingly demanding environments and applications.
By the 1960s, there was a growing demand for a polymer that was more chemically resistant and could withstand greater temperatures. Perfluoroelastomers compounds, abbreviated as FFKM, which combine the chemical resistance of PTFE[1] with the flexibility and elasticity of traditional FKMs[2], provided an effective solution to the challenge.
The Demand for a Stronger Elastomer
FFKMs receive greater elasticity due to their fluorinated backbone (and higher fluorine content than fluoroelastomer or FKM compounds), which makes them an excellent choice in a variety of demanding applications. When first introduced, they were considered the next stage of elastomer technology and were almost entirely the domain of space programs and chemical operations. However, once their positive features were fully recognized by the material science world, it was quickly adopted by the larger industrial community. Nowadays, FFKM is a common sight in numerous industries.
Selection of the appropriate elastomer for a given application is critical for the successful and long-term operation of the equipment. FFKM is well-suited for usage in highly aggressive chemical processing, semiconductor wafer production, pharmaceutical processing, oil and gas recovery, and aerospace applications. Although the polymer structure has essentially remained unaltered since the debut of perfluoroelastomers, the polymerization method has been refined over the decades, and FFKM materials can now be manufactured as part of a safer, greener manufacturing process.
Why FFKM is better than FKM
FFKM and FKM, like all elastomers, are typically compounded with fillers, processing aids, and other additives. Examples of common fillers include carbon black, mineral fillers such as silica, talc, clay, and polymeric fillers. Mechanical characteristics, chemical resistance, plasma resistance, and thermal stability of the finished material are highly influenced not only by the polymer but also by the other elements in the compound formulation.
For applications requiring harsh chemicals at temperatures up to 620°F (325°C), FFKM elastomers fill a critical gap. They are the most chemically resistant elastomers on the market, with exceptional temperature and chemical resistance. It is resistant to over 1,800 chemical compounds, including hydrocarbons, lubricants, and fuels. They are also resistant to steam, ozone, and weathering, and have a low gas permeability. They also offer a high level of static and dynamic load dependability due to their low compression set.
Advantages of FFKM
- Wide temperature range (-55°C – 330°C).
- Universal chemical resistance (best in class, similar to PTFE).
- Excellent gas and liquid permeation resistance.
- Excellent weather ability and ozone resistance.
- Self-extinguishing and non-flammable in air.
- High Density.
- Good mechanical properties, improving sealing performance.
- Compatible to ultra-pure manufacturing.
- Resistant to explosive decompression.
- Resistant to compression set.
Manufacturing Methods Using FFKM
Manufacturing of high performance FFKM-based products begins with the use of specialized molding presses. The injection molding technique forces raw material into a mold, which molds it to the desired shape. On the other hand, when the compression method is used, molding is preceded by raw material preparation via an extrusion system. Once extruded, the elastomer is ready to be put into the press, where it is formed into the desired formation using high pressures and high temperatures. All gaskets eventually undergo a process that distinguishes them from the burr found on newly molded items. Some FFKM applications, like those used in semiconductor fabrication and pharmaceutical processing, require sealing products that are of a superior purity level (ultra-pure). The ultra-pure manufacturing process is carried out in a separate manufacturing cell, using equipment dedicated to the production of premium fluoroelastomers. This cutting-edge cell protects products from contamination caused by dust, mold sprays, foreign materials, handling, and other common causes. Each stage in the ultra-pure manufacturing process, from material formulation through final product packaging, is subject to measurement, assessment, and statistical process control. As a result, the product has unrivaled purity and consistency.
Why FFKM Is Preferred
Despite some limitations, FFKM’s can be a smart material selection because of the efficiency and operational gains. Long-term, proven performance of FFKM parts can mean fewer seal replacements, repairs, and inspections, resulting in increased process and equipment uptime and yield.
[1] Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. Polytetrafluoroethylene is a fluorocarbon solid (at room temperature), as it is a high-molecular-weight polymer consisting wholly of carbon and fluorine.
[2] Fluoroelastomers or Fluorocarbons (FKM) are highly fluorinated polymers that are suitable for continuous use at elevated temperatures. Various grades are available, including copolymer and terpolymers. Fluoroelastomers have excellent heat and flame resistance, and outstanding resistance to aging, ozone, oxidizers, oils and many chemicals.
Are you interested in learning more about Friction Sealing Materials News? Contact us today to secure an expert consultation!