How is silicone rubber used for sealing and insulation? Silicones have valuable properties, but engineers need rubber that meets specific requirements. If you’re wondering whether silicone seals, gaskets, or insulation are the right choice for your application, consider some of the uses for this versatile polymer. The examples you’ll read about aren’t the only uses for silicone, but they’re representative. Continue reading
Elasto Proxy custom-fabricates silicone gaskets with high flex-fatigue resistance. These specialty gaskets are made of materials that meet the A-A-59588 3B specification for 50, 60, and 70-durometer silicones.
Silicone gaskets have many desirable properties. They’re chemically inert, resistant to ozone and ultraviolet light, offer thermal stability over a wide temperature range, and can repel water and form watertight seals. Silicone rubber is used in a variety of sealing and insulation applications, but some silicones have inadequate flex-fatigue resistance – a measure of a material’s ability to withstand repeated flexing or bending without cracking.
In some industries, however, flex-fatigue resistance is required. For example, aerospace engineers need silicones with high flex-fatigue resistance for door seals, window seals, and vibration-isolating mounts used with alternators, compressors, and assembly bolts. Members of the mobile equipment industry need crack-resistant silicones for engine mounts and exhaust hangers. Designers of aerospace and defense electronics need silicones that can flex without cracking in high-performance keypads. Continue reading
Technical buyers and design engineers need to evaluate all of their application requirements when specifying acoustic insulation. Sound dampening and sound absorption aren’t the same, and some acoustic materials may not be suitable for specific environments or frequencies.
Noisy equipment can cause hearing loss and result in violations that carry fines and other penalties. In North America, regulatory agencies such as OSHA, NIOSH and the Canadian Center for Occupational Health and Safety (OHS) establish workplace limits for noise exposure. Yet the fact remains that noise and hearing loss are the second most prevalent self-reported work-related injury, according to the Hearing Research Laboratory at the University of Ottawa.
Noise can also affect perceptions of product quality. That’s why some potential car buyers listen to how a vehicle’s door sounds when it closes. In a sports car, engine noise suggests speed and power. In a tractor, dump track, or military vehicle, loud engine sounds within the cab are unwanted. For technical buyers and design engineers then, noise mitigation can be about enhancing worker safety, ensuring regulatory compliance, improving the customer experience – or all of the above.
Acoustic insulation is essential, but what are some design considerations? In other words, what do buyers and designers need to know? Continue reading
Acoustical foams absorb and dampen sounds. Some of these foam rubber materials also provide flame resistance. Product designers need more than just an acoustic foam, however. They need a custom fabricator who can convert stock materials into a custom insulation solution.
Acoustic foams are used for sound absorption and sound dampening in applications such as military vehicles, commercial trucking, and equipment enclosures. They’re usually made of silicone, urethane, or foam-based melamine. Some acoustical foams offer additional properties, such as thermal resistance or fire resistance. For specialized applications, acoustical foams can be added as layers within “insulation sandwiches” that also contain fillers, adhesives, and barrier materials. Continue reading
Doug Sharpe President of Elasto Proxy
Learn why the aerospace industry sources seals, gaskets, and insulation from Elasto Proxy, a custom fabrication specialist with offices in Canda, the United States, and China.
Did you know that aerospace manufacturing is flying high in North America? As reported recently in Industry Week, aerospace investment in the U.S. has increased by over $25 billion since 2012. Here in Quebec, Canada, where Elasto Proxy is headquartered, analysts are also optimistic. Maybe you knew that Boeing and Airbus are expanding production in the continental United States, but did you know that Montreal is one of the world’s top three aeronautics hubs?
Here in Boisbriand, just a short drive from Montreal, Elasto Proxy has grown alongside the aerospace industry. Today, Quebec is home to over 200 aerospace companies, research centers, and associations. Our aeronautics industry employs over 40,000 highly-skilled workers, and Quebec’s universities and technical schools train nearly 5,000 students each year. Bell Helicopter Textron, Bombardier Aerospace, CAE, and Pratty & Whitney Canada all call this part of Canada home.
Sealing Solutions That Last
As a growing, global company, Elasto Proxy monitors trends in both the civilian aircraft industry and in military markets. For over 25 years, we’ve used our technical design and custom fabrication expertise to solve sealing and insulation challenges in a variety of industries. Recently, a major defense contractor accepted our advice about hatch seals. Maintenance personnel don’t always have the rubber parts that they need in the field, and taped parts adhere reliably so that frequent replacements aren’t required.
By listening to the aerospace company’s needs and applying our application experience, Elasto Proxy won an award for taped parts. Using our compact taping machine, our Boisbriand facility can supply gaskets with either a heat-activated adhesive taping system (HATS) or a pressure-sensitive adhesive (PSA). Developed by 3M, HATS features strong stress-handling and weatherstripping capabilities, making it a sound choice for permanent sealing and outdoor applications. HATS high-bond tape takes 24 hours to fully-cure, but provides the kind of adhesion and holding strength that aerospace companies require.
Aerospace Seals That Won’t Go Up in Smoke
Tier 1 and Tier 2 suppliers to aircraft manufacturers can also benefit from our industry knowledge. For example, aerospace engineers may need to source materials that meet ABD 031, the Airbus standard for fire testing, flammability, smoke, and toxicity (FST). Boeing also maintains its own fire testing standards: BSS 7238 for smoke density, and BSS 7239 for toxicity. Elasto Proxy can help with compound selection, and then design and custom-fabricate fireproof rubber products such as seals, gaskets, and insulation.
Our solutions providers can also help technical buyers source elastomers that meet Bombardier SMP 800-C and ASTM’s Aerospace Material Standards (AMS). The AMS specifications cover a variety of areas, including transparent enclosures and materials. AMS standards apply to passenger aircraft, of course, but did you know that they apply to unmanned aerial vehicles (UAVs), too? If you need EMI RFI shielding for UAV power sources and guidance systems, ask Elasto Proxy about its gasket fabrication capabilities.
Like the aerospace industry, Elasto Proxy is growing globally. Since our founding in 1989, we’ve expanded to Ontario, Canada; Simpsonville, South Carolina; and Shanghai, China. Today, Ontario’s aerospace industry is the second largest in Canada, and 14 of the top 25 firms are located in Canada’s most populous province. From aircraft integration and assembly to helicopters, engine systems, and aircraft component manufacturing, our warehouse near Toronto can supply the rubber parts you need.
In the southern United States, Elasto Proxy’s sales office and warehouse isn’t far from Boeing in South Carolina, Airbus in Alabama, Gulfstream Aerospace in Georgia, and GE Aviation in North Carolina. China is flying high in terms of aerospace manufacturing, too. From our office in Shanghai, we’re ready to work with civilian aircraft manufacturers, domestic companies, and foreign subsidiaries. Shanghai itself is an aerospace center, and home to the Shanghai Aircraft Design and Research Institute (SADRI).
How Can We Help You?
How can we help you? To learn more about Elasto Proxy’s aerospace capabilities, watch this short video. Then, when you’re ready to strengthen your supply chain, contact us for high-quality seals, gaskets, and insulation.
Doug Sharpe President of Elasto Proxy
Electromagnetic interference (EMI) can disrupt military electronics and endanger the lives of the war-fighters who depend on them. The causes of EMI are numerous, and include everything from electric motors and radio transmitters to computer circuits and power lines. Electronic jamming or intentional EMI (IEMI) also concerns military planners. Military radios, cameras, sensors, and telecommunications systems can experience interruptions during battlefield conditions, or suffer permanent damage.
Several global incidents underscore these concerns. In May 2012, over 500 airplanes in South Korea experienced global positioning system (GPS) failure from electromagnetic fields that were traced to the North Korean city of Kaesong. Two years earlier, North Korea reportedly purchased truck-based systems that could jam GPS signals. IEMI weapons were used in Chechnya against the Russian military, and in Moscow against a standard telephone system.
Environmental Sealing and EMI Shielding
Military environments are especially challenging, so technical buyers and electronic designers need to select materials with the right balance of properties. Particle-filled silicones are elastomeric compounds that combine the advantages of silicone with the electrical characteristics of metals. An inert, synthetic rubber, silicone offers thermal stability over a wide temperature range and resists ozone and ultraviolet (UV) light. Silicone rubber also resists water, and can be formulated to impart electrical conductivity.
When filled with metal particles, silicone compounds can be used to fabricate gaskets that provide both environmental sealing and EMI shielding. Metal fillers include particles made of pure silver, silver-plated aluminum, or silver-plated copper. Conductive silicones that are filled with silver-plated glass, nickel-plated graphite, and carbon black are also available. Before choosing a compound, however, buyers and designers need to understand application requirements and applicable military standards.
MIL-DTL-83528C is a general specification from the U.S. Department of Defense (DOD) for electrically-conductive elastomeric shielding gaskets. Released in January 2001, it supercedes the MIL-G-83528B standard that is sometimes still referenced in data sheets. MIL-DTL-83528C sets requirements for part identifying numbers (PIN) and contains a Material Type section with lettered designations for both silicone and fluorosilicone compounds.
For example, Type B materials are silver-plated, aluminum-filled silicones that are capable of 100 dB of plane wave shielding effectiveness at 10 GHz with a continuous use temperature range from -55°C to +160°C. Conductive fluorosilicone shielding materials also carry shielding effectiveness and temperature specifications, and offer resistance to solvents and jet fuels. By understanding your sealing and shielding requirements, an EMI gasket fabricator can recommend the right material.
How Can We Help You?
Does your project require a Type B silver-plated, aluminum-filled silicone with a Qualified Products List (QPL) acknowledgement from the Defense Logistics Agency (DLA)? Elasto Proxy can source cost-effective conductive compounds for you, and them custom fabricate high-quality EMI gaskets. Our solutions providers can also source EMI shielding materials that are designed to meet the requirements of other parts of the MIL-DTL-83528C specification
For over 25 years, Elasto Proxy has custom-fabricated specialty seals and custom insulation for military and defense. How can we help you with EMI gasketing? Contact us today, or join the conversation about this blog entry on LinkedIn, Facebook, Google+, and Twitter. Elasto Proxy has a YouTube channel, too. There, you’ll find our Capabilities video, as well as other informative content. Finally, please subscribe to our free e-newsletters.
Philippe Grenier Production Coordinator at Elasto Proxy
Subway, bus, and railcar designers prefer lightweight rubber materials, but some combustion reactions can produce dangerous toxins. Reducing a vehicle’s weight can help cut fuel consumption, but material selection shouldn’t come at the expense of passenger safety. Technical buyers and part designers in the marine and aerospace industries share these concerns. Boats, ships, helicopters, and airplanes also need fireproof rubber parts such as seals, mats, gaskets, hose, flooring, and insulation.
Rubber Parts and the Right Partner
Fireproof rubber isn’t something that most passengers notice, but it’s all around them. Specialty elastomers are used in door and window seals, floor coverings and ceiling liners, and interior vehicle components such as wall panels, seat pads, and mattress frames. Fireproof rubber is also used in the cellular foams for armrests, acoustic insulation for passenger cars, and thermal insulation for engine bays. Outside the vehicle, rubbers parts such as end caps and roof housings must resist fire, too.
For designers and buyers in the mass transit, marine, and aerospace industries then, choosing the right rubber is critical. Standard, off-the-shelf profiles are available, but custom-fabrication may be required. By partnering with a supplier who listens to your needs and analyzes your safety requirements, you can strengthen your supply chain. Yet it’s also important to pick a partner who understands how fireproof rubber products are specified, and what different fire safety standards mean.
Flammability, Toxic Gases, Heat Release, and Smoke Development
The UL 94 flame rating from Underwriters Laboratories (UL) classifies rubber materials according to how they burn when vertical or horizontal, and in different thicknesses. For example, UL 94-HB is a horizontal burn test for specimens thicker than 76 mm. UL VTM-0 is a vertical burn test, but for materials that are too thin for flame tests such as UL V-0. For technical buyers then, choosing UL listed gasket materials may require an analysis of application requirements for material thickness and part orientation.
In the mass transit industry, meeting the Bombardier SMP 800-C standard for toxic gas sampling and analytical procedures is also critical. Using a calibrated chamber for smoke generation testing, this test measures the concentration of various gases (such as carbon monoxide) in both flaming combustion and non-flaming thermal decomposition modes. Fire, smoke, and toxicity (FST) tests for buses, subways, and railcars may also include ASTM E1354, which measures heat release and smoke development.
Tests, Standards, and Industry Requirements
UL 94, Bombardier SMP 800-C, and ASTM E1354 are important, but they’re not the only standards for fireproof materials. Depending on your industry, location, and customer, other tests and standards may apply. For example, aerospace engineers may need to source materials that meet ABD 0031, the Airbus standard for fire testing, flammability, smoke, and toxicity. Boeing also maintains its own fire testing standards: BSS 7238 for smoke density, and BSS 7239 for toxicity.
For marine buyers, the International Maritime Organization (IMO) provides a nine-part fire testing standard with a special focus on normal flammability, smoke density, and smoke toxicity. NFPA 130:2010 from the National Fire Protection Agency (NFPA) is designed for fixed guideway transit and passenger rail systems, but incorporates ASTM standards as well as Bombardier SMP 800-C, BSS 7238, and BSS 7239.
For both the automotive and mass transit industries, FMVSS 302 from the U.S. National Highway Safety Traffic Administration (NHTSA) specifies burn resistance requirements for materials used in occupant compartments. Technically equivalent to ISO 3795 and ASTM D5132-04, FMVSS 302 applies to buses, trucks, passenger cars, and multi-purpose passenger vehicles. The purpose of FMVSS 302 is to reduce deaths and injuries caused by vehicle fires, especially those originating in a vehicle’s interior.
How Can We Help You?
As a growing global company with partners in a wide variety of industries, Elasto Proxy can help you to source fireproof rubber products for mass transit, marine, and aerospace applications. Ask how we’ve helped retrofit railcars with neoprene door seals, and can supply custom composite insulation and self-extinguishing firestocks. Our solutions providers can also source specialty silicones, fireproof foams and extrusions, and hard-to-find fire-rated bulb trims.
So how can we help you? For more information, please contact us or request a quote. Join the conversation on our social media sites, too. Look for a post with a link to this blog entry on LinkedIn, Facebook, Google+, and Twitter. Elasto Proxy also has a YouTube channel, too. Finally, please subscribe to our free e-newsletters. They’re a great source of information delivered right to your email inbox, and they provide links to blog entries like this one.
Doug Sharpe President of Elasto Proxy
Have you ever wondered why you’re not allowed to use your cell phone on an airplane or in a hospital? It’s because cell phones produce electromagnetic fields that can interfere with avionics and medical equipment. If electromagnetic interference (EMI) disrupts in-flight communications, a pilot may not be able to receive radio transmissions from an air traffic control tower. EMI can also endanger patients in hospitals, where it can cause medical devices such as ventilators or heart monitors to malfunction.
EMI can be so powerful that defense and security experts worry about its intentional use by criminals, hackers, and terrorists. Electronic jamming isn’t new, but the proliferation of wireless devices and electronic communications increases our vulnerability. Preventing inadvertent or intentional EMI from disrupting electronic communications can’t be an afterthought in the design process. After all, ensuring electromagnetic compatibility (EMC) could mean the difference between life and death.
Metal Enclosures and More
When designing electronic devices, manufacturers must follow regulations for preventing EMI and RFI, a form of EMI in the radio frequency (RF) part of the electromagnetic spectrum. By using EMI shielding, electronic designers can reduce – or attenuate – this interference. Through a combination of reflection and absorption, EMI shielding opposes the invisible waves of electromagnetic energy that can cause communication failures. EMI shields were once almost exclusively metal, but have evolved over time.
Back in the days of Bell Telephone, technicians maintained grounded cabinets made with beryllium fingers. These metal enclosures protected sensitive components from outside interference while containing electronic emissions. Buyers of EMI shielding also opted for wire mesh made of different metals, and that included elastomeric cores made of tubing or sponge-like materials. These cores supported the metal mesh during installation and helped it to retain its shape.
During the 1980s, product designers began to use loaded materials – silicones with metal inside. EMI shielding also evolved as more applications required lower-cost, lighter-weight, and easier-to-produce solutions. Metal enclosures made of aluminum, steel, nickel, and nickel-iron alloys are highly effective against EMI, but cost more than lighter-weight thermoplastics that are produced with injection molding rather than metal stamping.
Thermoplastic Enclosures and Conductive Coatings
Plastic products alone cannot provide adequate EMI protection, however. Because plastic materials are electrically insulating, internal electric charges do not flow freely. To overcome this inherent condition, conductive coatings are applied, often through electroless plating. This labor-intensive chemical process deposits a thin layer of metal onto the plastic after the substrate is exposed to solvent, etched with acid and rinsed, and a catalyst is applied.
Although electroless plating remains popular, concerns about production costs, worker safety, and the environment are causing some companies to choose other coatings instead. Made with a thermoplastic or thermosetting resin, these alternative coatings are loaded with metallic particles like silver, copper, or nickel. Instead of filling or loading the plastic part with metal then, conductive material is applied to the part’s surface (as with electroless plating).
Highly-conductive epoxy coatings for thermoplastic enclosures are another choice for EMI shielding. Lightweight and self-assembling, these polymeric coatings provide resistance to high temperatures, humidity, and marine environments. Unlike traditional coatings, they are available as adhesives and films. Highly-conductive epoxy coatings can be sprayed onto plastic parts with consistent coverage, but without the cost, safety, and environmental drawbacks associated with electroless plating.
How Can We Help You?
For over 20 years, Elasto Proxy has supplied sealing solutions to a wide variety of industries, including military, medical, and marine applications. To outfit our partners with an environmental seal that provides EMI shielding, we’ve custom-fabricated high-quality silicone profiles with wire mesh. Our experience with EMI shielding also includes working with defense contractors on sealing solutions for mobile military communications centers that must resist electronic jamming.
How can we help you? Let’s talk about EMI shielding. Join the conversation. Look for my post with a link to this blog entry on LinkedIn, Facebook, Google+, and Twitter. Elasto Proxy has pages on all of these social media websites, so all that’s missing is you! I also hope you’ll subscribe to our free e-newsletters, too. They’re a great source of information delivered right to your email inbox.
Clyde Sharpe President of International Sales
Is aluminum the best choice for building the bodies of space vehicles? Pure aluminum lacks the tensile strength needed for airplanes and helicopters, but aluminum alloys with magnesium and silicon are materials of choice in spacecraft. Pound for pound, alloys such as aluminum 6061 with T6 temper are stronger than some steel alloys. Aluminum aerospace alloys offer flame and chemical resistance, too.
So why would scientists and engineers consider plastic parts instead? Although aluminum alloys are lightweight – a key consideration in applications where every pound or kilogram counts – they provide relatively little protection against the high-energy cosmic rays that would harm humans on a mission to Mars. High-performance aerospace plastics offer additional benefits as well.
Tissue-Equivalent Plastics (TEP)
Spaceflight exposes travelers to several forms of radiation. Radiation belts around Earth trap charged particles from the Sun, which also erupts in solar flares that release intense radiation. Cosmic rays from objects outside our solar system also bombard spacecraft with high-energy particles. Like solar flares, these cosmic rays can also cause electromagnetic interference (EMI) with spacecraft instruments.
Astronauts with the Apollo program were subjected to only minor doses of radiation because they were outside of Earth’s orbit for just a few days. A manned mission to Mars, or even a long-term stay on the Moon, would require scientists and engineers to develop space vehicles with much more shielding. At the same time, any such “space age” material must all meet all other mission requirements.
According to researchers from the University of New Hampshire and Southwest Research Institute, tissue-equivalent plastics (TEP) have promise. Using observations made by the Cosmic Ray Telescope for the Effects of Radiation (CRaTER), the researchers determined that TEP, which simulates human muscle, provides better shielding than aluminum against radiation in space.
High-Performance Aerospace Plastics
The advantages of high-performance plastics are well-known in the aviation and aerospace industries. Plastics are approximately 50% lighter than aluminum and, unlike other metals, do not corrode. Modern polymers also provide a high degree of design freedom and can be fabricated into custom components. Fiber-reinforced plastics (FRP) offer increased strength and resistance to deformation.
Aerospace manufacturers also use transparent plastics, a lightweight, impact-resistant alternative to glass. Plastics with modified sliding properties are recommended for dry applications under extreme conditions because of their lubrication properties. High-performance aerospace plastics also offer high thermal and mechanical stability, inherent flame resistance, and a low degree of thermal expansion.
Join the Conversation
Would you fly on a spacecraft made of plastic parts? To join the conversation, look for my post with a link to this blog entry on LinkedIn, Facebook, Google+, and Twitter. Elasto Proxy has pages on all of these social media websites, so all that’s missing is you! We also hope you’ll subscribe to our free e-newsletters. They’re a great source of information delivered right to your email inbox.
The global aerospace market is growing, and Elasto Proxy will continue to bring you insights about the role of high-quality rubber and plastic components. As a supplier of sealing solutions to the aerospace industry, our custom fabrication capabilities include hatch seals, door and window seals, interior sealing products, and thermal and acoustic insulation for airframes aircraft engines. Keep in touch!