Elastomeric Material Products

An elastomeric material is any material exhibiting elastic or rubber-like properties. Elastomeric materials are measured in material type, compound, and durometer (the material’s hardness). Since there are such a wide variety of elastomeric materials, the application is critical to understanding the job’s best material compound.

Elastomeric Material Comparison Data Sheet

Foam / Sponge

Foam and sponge are generally grouped and regarded as in the same elastomeric/plastic materials family because they exhibit the same cellular structure. Additionally, they are commonly listed under similar industry specifications (ASTM, MIL, UL, FMVSS, and others).

Foam is a lightweight, open-cell product that is typically used for insulation, filtration, and cushioning. These low density cellular materials allow air movement through the cell structure. In addition to traditional foam’s legacy applications, high-density foams have been developed for fluid sealing applications. In contrast, higher-density foam products will have a higher concentration of cells. Medium and low-density foams will have a lower concentration of cells.

The sponge is an expanded, rubber-based elastomeric material. The sponge can be processed in multiple material formulations (different compounds, densities, and open and closed cellular structures). The cells are not connected, which keeps the material from absorbing and retaining liquid. Compared to foams, sponges are considered to have superior mechanical properties.

Sponge and Foam are available in sheets, rolls, and molded or extruded shapes. As needed, they can be ordered with or without ‘skin’ and PSAs (pressure-sensitive adhesive).

COMMON BRANDS: Rogers, Monmouth, Armacel, K-Flex, Rubatex, Griswold
COMMON TRADE NAMES: Poron, Bisco, EnsoLite®

COMMON USES:

• Filtration
• Thermal Insulation
• Cushioning
• Padding
• Gaskets
• Weather Stripping
• Sound Barrier

To learn more about foam and sponge elastomeric material from The Gund Company or request a quote for your application, Contact Us Today!

Rubber

Rubber is often referred to as a “solid elastomeric.” Generally speaking, the two most common types of rubber are natural and synthetic. Natural (gum) rubbers are derived from the rubber tree. Conversely, rubber-like materials from sources other than the rubber tree are commonly referred to as synthetic rubber.

Though there are currently more than 36 synthetic rubber compounds available, not all are commonly used. Rubber compounds have been researched, developed, and engineered to meet many application requirements, including fluid, temperature, and pressure resistance. Many synthetic rubber materials are also available with different degrees of reinforcement, such as cloth inserted (CI) or fabric reinforced (diaphragm). These materials are designed specifically to meet a variety of customer applications.

COMMON TRADE NAMES: Nitrile [Buna-N], Neoprene, Silicone, FKM [Viton®], EPDM, SBR, and many more.

COMMON USES:

• Gaskets
• Diaphragms
• Seals
• Chute Lining
• Seats
• Extrusions
• Door Seals
• Molded Seals [Shapes]
• Tubing
• Bumpers
• Pads
• Grommets
• Washers

To learn more about rubber elastomeric materials from The Gund Company or request a quote for your application, Contact Us Today!

O-Rings

O-rings’ primary functions are to create a barrier between two items where air or fluid may escape. They are typically installed in a groove to hold them in place while squeezed between two opposite surfaces. In most cases, O-rings are sized using the inside diameter (ID) by Cross Section (CS). O-rings are particularly effective because they have memory and want to expand to their original size and shape. So, compressing them between two opposing surfaces creates an air or fluid-tight seal. O-rings are available in a variety of natural and synthetic rubber compounds. Depending on the application, the material chosen can significantly impact the functionality of the O-ring.

Though they are a common commodity, choosing the proper O-ring for the application can be challenging considering thermal resistance and degradation from fluid and gasses. Additionally, there are several standards for O-rings worldwide. The most common standard for North America is AS568. We understand the various mechanical properties of O-ring materials. Contact one of our material specialists today to review your applications or request a quote.

O-rings are available in most polymer compounds and sizes, including AS568B [chart below], Metric sizes, both molded and vulcanized endless from the O-ring cord. REQUEST A QUOTE

APPLICATIONS:

• Hydraulics
• Faucets
• Gaskets
• Setting Tools
• Frac Plugs
• Carburetors
• Gas Valves
• Helicopters

• Section Diameter of AS568-001 is 1/32                * Sectional diameter of AS568-002 is 3/64

To learn more about O-Ring materials from The Gund Company or request a quote for your application, Contact Us Today!

Visit our material datasheets Section for more information.

EMI Shielding / Thermal Management

EMI Shielding and Thermal Management are generally grouped together. They are commonly listed under similar industry specifications.

EMI Shielding: Electromagnetic Interference has become far more significant in recent years as the use of electronic devices continues to increase. As the utilization of these devices continues to grow, so does the exposure to a wide range of frequencies. Through years of research and development, manufacturers have determined that electrical insulation, enclosures, and cables are effective ways to contain these frequencies.

Organizations such as the CE & FCC have provided guidelines in the form of legal requirements to prevent electromagnetic interference (noise). As such, EMI Shielding has become a necessity in the electronics industry. Since there are a wide variety of application designs and frequency requirements, various materials have been developed to provide adequate shielding.

Thermal Management: Historically, thermal grease was used to create continuity between power sources and heat sinks. Unfortunately, this grease was not ideal in applications where ease of installation and cleanliness were paramount. These days, many applications utilize thermally conductive materials or thermal management in place of this grease.

Thermally conductive compounds contain fillers that maintain flexibility in service while providing continuity between the mating surfaces. In electronic equipment, air acts as an insulator and must be eliminated for optimum performance. Manufacturers of electronic devices want to establish an anaerobic environment to allow continuity between the power source and heat sink for proper performance. Such thermal management products create continuity within the component to optimize the heat dissipation from the power source.

Thermal management products are used in an expansive list of applications. As such, there are an equally wide variety of thermal management options available.

The Gund Company is well versed in EMI Shielding and Thermal Management Contact one of our material specialists today to review your applications or request a quote.

Cork/Rubber

Cork and rubber products are instrumental in metal-to-metal joints. If a proper firmness material is selected, no allowance for the side flow needs to be made. The compressibility of cork and rubber can be used in place of more expensive non-compressible rubber seals. Some of the friction of cork is retained in these products and helps to reduce extrusion and slippage.

Cork and rubber products can easily contain sponged materials that conform to and compensate for minor flange irregularities. This characteristic is especially useful in stamped or other lightweight assemblies where the available bolt spacing and bolt load are usually low.

Cork/rubber products have an unusual resilience which helps resist compression set and other effects of fatigue. Cork and rubber seals are more resistant to aging than traditional rubber compounds.

Cork and rubber compounds are used to establish and maintain intimate contact between the flanges. The most common synthetic rubber compounds are Neoprene® and Nitrile. However, special applications may use cork material blended with Hypalon®, Silicone, Fluoroelastomer, SBR, or Vamac.

COMMON BRANDS: ECORE Intl, Amorim Cork Solutions
COMMON TYPES: Composition Cork, Cork & Neoprene, Cork & Nitrile, Cork & Sponged Rubber

COMMON USES:

• Air Compressors
• Air Pumps
• Carburetors
• Electric Motors
• Fuel & Oil Pumps
• Fire Hydrant Valves
• Gear Boxes
• Heat Exchangers
• Meters
• Pipe Flanges
• Pumps
• Transformers
• Transmissions

To learn more about cork/rubber material from The Gund Company or request a quote for your application, Contact Us Today!

Visit our material datasheets Section for more information.

Felt & Wool

Natural wool felt is one of the oldest manufactured textiles. Many cultures have legends as to how the felting process was discovered. One of the earliest accounts of felting details how nomads fleeing persecution packed their sandals with wool to prevent blisters while crossing the desert. At the end of their journey, the movement and sweat had turned the wool into felt socks.

Felt is a textile material produced by matting, condensing, and pressing fibers together. Felt can be made of natural fibers such as wool or animal fur or synthetic fibers such as petroleum-based acrylic or acrylonitrile, or wood-based rayon. Blended fibers are also standard. Felt has unique properties that allow it to be used for various purposes. “It is fire-retardant and self-extinguishing; it dampens vibration and absorbs sound, and it can hold large amounts of fluid without feeling wet.

Felt from wool is the oldest known textile. Many cultures have legends as to the origins of felt making. Sumerian legend claims that Urnamman of Lagash discovered the secret of felt making. The story of Saint Clement and Saint Christopher relates that the men packed their sandals with wool to prevent blisters while fleeing persecution. At the end of their journey, the movement and sweat had turned the wool into felt socks.

Today’s pressed wool felt is made via an intricate process called “wet processing.” Fibers are combined by applying pressure, moisture, and vibration, then carded and cross-lapped to make multiple material layers. The material’s ultimate thickness and density determine the number of steamed, wetted, pressed, and hardened layers.

In the wet felting process, hot water is applied to layers of animal hairs. Repeated agitation and compression cause the fibers to hook or weave into a single fabric piece. Wrapping the properly arranged fiber in sturdy, textured material, such as a bamboo mat or burlap, will speed up the felting process. The felted material may be finished by fulling.

Specifications: SAE/C-F-206G

The majority of fiber used in pressed felt is wool. Wool fibers have small barbs on them, which aids in the natural locking or felting process. The manufacturing of pressed wool felt is primarily mandated by SAE standards. These standards determine the wool content, density, and other physical and mechanical properties of the felt. Pressed wool felt is identified by the SAE standards F-1 thru F-26.

The lower the SAE numbers, the more machinable, have better vibration absorption, and better abrasion resistance. Wool felt has excellent wicking properties. It can absorb its weight in oil several times, and when used as a lubrication wick, it will supply small amounts of oil at a uniform rate. Pressed wool felt has excellent solvent resistance and stability in oil. SAE wool felt is unaffected by sunlight and maintains its original form after long periods of stress.

COMMON TYPES: Wool, Polyester, High Temperature
COMMON TRADE NAMES: NOMEX

APPLICATIONS:

• Gaskets
• Wicking
• Dust Shields
• Grease Retainer
• Sound Reduction
• Wipers
• Weather Stripping
• Pads

US Federal Specification C-F-206G

Felt & Polyester

Polyester felt is a synthetic needle-punched felt made from polyester fibers. Material is normally supplied in either black or white. This general-purpose felt is made in various densities, ranging from .019” to 2”. Polyester felt is inexpensive and often made in comparable density and thickness to SAE pressed wool felt. The maximum temperature of polyester felt is 300oF, compared to 200oF for SAE pressed felts. This material can be used for filtration applications, gaskets, wipers, and padding in various industries. The density of polyester felt is commonly measured in ounces/sqyd.

Polyester felt is usually supplied in either black or white, in various densities and thicknesses ranging from .019” to 2.0” thickness.

APPLICATIONS:

• Filtration
• Gaskets
• Weatherstripping
• Wipers
• Crate lining
• Padding

To learn more about felt in wool or polyester material from The Gund Company or request a quote for your application, Contact Us Today!

Visit our material datasheets Section for more information.