Elastomeric Materials

ELASTOMERIC MATERIALS

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 is such a wide variety of elastomeric materials, the application is critical to understanding the job’s best material compound.

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 material. The sponge can be processed in multiple material formulations (different compounds, densities, or 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®
1.4 Elastromeric Materials 123 Sponge and Foam

USES:

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

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

SPONGE SPECIFICATION GUIDE
Polymer NEO/EPDM/SBR EPDM/BLEND EPT BLEND
Specification
ASTM D1056-67 SCE41 SCE42 SCE43 SCE45 RE41E RE42E RE43E RE41EPT
ASTM D1056-07 2A1 2A2 2A3 2A5 2A1 2A2 2A3 2A1
MIL-R-6130 TYP + ASTM D6576 II-A II-A II-A II-A II-B II-B II-B —–
GRADE CONDITION Soft Soft-Med Medium Firm Soft Soft-Med Medium —–
MIL-C-3133C MIL STD 6708 SCE3 F2 SCE7 F2 SCE11 F2 SCE20 F2 RE3 F2 RE7 F2 RE11 F2 RE3
FLAMMABILITY SPECIFICATION
UL94 HF1 Listed Listed Listed —– —– —– —– —–
UL94 HBF Listed Listed Listed —– —– —– —– —–
MIL-R-6130C Pass Pass Pass Pass Pass Pass Pass —–
FMVSS-302 Pass Pass Pass Pass Pass Pass Pass —–
PHYSICAL PROPERTIES
25% Compression Deflection [psi] 2-5 5-9 9-13 17-25 2-5 5-9 9-13 2-5
Density Approximate [pcf] 6 +/-2 6 +/-2 9 +/-2 12 +/-2 6 +/-2 6 +/-2 9 +/-2 4 +/-1
Water Absorption Max. Weight % 5 5 5 5 5 5 5 5
Temperature Range oF -40/+200 -40/+200 -40/+200 -40/+150 -70/+220 -70/+220 -70/+220 -40/+200
Temperature High Intermittent oF 250 250 250 200 250 250 250 250
Ozone Resistance Excellent Excellent Excellent Fair Excellent Excellent Excellent Excellent
Tensile Strength [psi] 75 100 100 150 75 75 100 40
Fuel B Max. % Weight Change n/a n/a n/a n/a n/a n/a n/a n/a
Elongation Typical Properties % 125 125 125 125 125 125 125 175
Durometer Shore 00 [Approx.] 40-50 45-55 55-65 65-75 40-50 45-55 55-65 37-47
Shrinkage 7 Days @ 158o Max. 5% 5% 5% 5% 5% 5% 5% 5%
K Factor 0.30 0.30 0.38 —– 0.3 0.30 0.38 030
Polymer 100% NEOPRENE EVA PVC/NITRILE
Specification
ASTM D1056-67 SCE41NEO SCE42NEO 2#EVA 4#EVA IV1 IV2 IV3
ASTM D1056-07 2C1 2C2 2A1/2A2 2A2/2A3 2C1 2C2 2B3
MIL-R-6130 TYP + ASTM D6576 II-A II-A —– —– 11-B 11-A/B 11-A/B
GRADE CONDITION Soft Soft-Med —– —– Soft Soft-Med Medium
MIL-C-3133C MIL STD 6708 SCE3 F1 SCE7 F1 —– —– SCE3 SCE7 SCE11
FLAMMABILITY SPECIFICATION
UL94 HF1 Pass Pass —– —– Listed Listed Listed
UL94 HBF Pass Pass —– —– Pass Pass Pass
MIL-R-6130C Pass Pass —– —– Pass Pass Pass
FMVSS-302 Pass Pass Pass Pass Pass Pass Pass
PHYSICAL PROPERTIES
25% Compression Deflection [psi] 2-5 5-9 4-6 9-13 2-5 5-9 9-13
Density Approximate [pcf] 9 +/-2 9 +/-2 2 +/-5 3.0-4.0 3.0-5.0 5.5-7.5 7.0-9.5
Water Absorption Max. Weight % 5 5 10 10 7 5 5
Temperature Range oF -40/+150 -40/+150 -110/+220 -110/+220 -40/+200 -40/+200 -40/+200
Temperature High Intermittent oF 200 200 240 240 225 225 225
Ozone Resistance Fair Fair Excellent Excellent Fair Fair Fair
Tensile Strength [psi] 80 90 60 100 50 75 100
Fuel B Max. % Weight Change <250 <250 n/a n/a <250 <250 <100
Elongation Typical Properties % 150 150 275 310 100 100 100
Durometer Shore 00 [Approx.] 45-55 50-60 —– —– 30-45 50-60 60-70
Shrinkage 7 Days @ 158o Max. 5% 5% 5% 5% 3% 3% 3%
K Factor 0.38 0.38 0.25 0.30 0.25 0.23 0.30
Polymer Closed Cell Silicone Sponge
Specification
AMS 3195 3196
MIL MIL-R-46089 MIL-R-46089
DENSITY
PHYSICAL PROPERTIES Soft Medium Firm Extra-Firm
25% Compression Deflection [psi] 5-9 6-14 12-20 16-28
Density Approximate [pcf] 31 33 40 45
Water Absorption Max. Weight % <1% <1% <1% <1%
Temperature Range oF -103 / +450 -103 / +450 -103 / +450 -103 / +450
Temperature High Intermittent oF
Ozone Resistance Excellent Excellent Excellent Excellent
Tensile Strength [psi] Good Good Very Good Very Good
Elongation Typical Properties % Good Good Very Good Excellent
Thermal Conductivity BTU 0.75 0.75 0.80 0.85
in/hr/ft3/oF
Dielectric Strength [approx] 150 volts/mil 150 volts/mil 150 volts/mil 150 volts/mil

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 produced 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) of 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
  • Fluorosilicone
  • and many more.
Elastomeric Materials From The Gund Company

COMMON USES:

  • Gaskets
  • Diaphragms
  • Seals
  • Chute Lining
  • Seats
  • Extrusions
  • Door Seals
  • Molded Seals [Shapes]
  • Tubing
  • Bumpers
  • Pads
  • Grommets
  • Washers
POLYMER CHARACTERISTICS
Polymers Acrylonitrile Butadiene Rubber Ethylene Propylene Fluoroelastomer Silicone
Common Names Buna-N, Nitrile, NBR EPR, EPT, EP, EPDM Viton®, FKM VMQ
ASTM D1418 Designation NBR EPDM, EPM FKM Q, MQ, PMQ, PVMQ
ASTM D2000 Type/Class BF, BG, BK, CH AA, BA, CA, DA HK FC, FE, GE
Mil-R-3065 [Mil-Std-417 Class SB RS TB TA
General Characteristics
Durometer Range [Shore A] 20-95 30-90 50-95 10-85
Tensile Range [psi] 200-3500 500-2500 500-2000 500-2500
Elongation Range % 350-650 100-700 400-500 450-900
Compression Set Resistance Good to Excellent Good Good to Excellent Excellent
Resilience / Rebound Good to Excellent Fair to Good Poor to Fair Good
Abrasion Resistance Good to Excellent Good Fair to Good Good
Tear Strength Good to Excellent Fair to Good Fair to Good Good
Solvent Resistance Good to Excellent Poor Excellent Poor
Oil Resistance Excellent Poor Excellent Poor
Low Temperature oF -70 -60 -30 -75
High Temperature oF +250 +300 +572 +500
Ozone Resistance Fair to Good Good to Excellent Excellent Excellent
Polymers Polychloroprene Styrene Butadiene Rubber Fluorosilicone Polyisobutylene
Common Names Neoprene SBR FVMQ Butyl
ASTM D1418 Designation CR SBR FVMQ IIR, BIIR, CIIR
ASTM D200 Type/Class BA, BC AA, BA FK AA, BA
Mil-R-3065 [Mil-Std-417 Class SE RS TA RS
General Characteristics
Durometer Range [Shore A] 20-95 30-95 40-80 40-90
Tensile Range [psi] 500-3000 500-2900 500-1500 500-2900
Elongation Range % 100-800 300-450 150-600 300-850
Compression Set Resistance Poor to Good Good to Excellent Very Good Fair to Good
Resilience / Rebound Fair to Good Good Good Fair to Good
Abrasion Resistance Good to Excellent Excellent Poor Fair to Good
Tear Strength Good to Excellent Fair to Excellent Poor Good
Solvent Resistance Fair Poor Excellent Poor
Oil Resistance Fair Poor Good Poor
Low Temperature oF -70 -60 -100 -70
High Temperature oF +250 +250 +450 +300
Ozone Resistance Good to Excellent Poor to Good Excellent Excellent

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 and/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 when considering thermal resistance and degradation from fluid and gases. 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
Elastomeric pipe insulation from The Gund Company
Cross Section Cross Section Cross Section
1/16 3/32 1/8 3/16 1/16 3/32 1/8 3/16 1/4 3/32 1/8 3/16 1/4
ID (.070) (.103) (.139) (.210) ID (.070) (.103) (.139) (.210) (.275) ID (.103) (.139) (.210) (.275)
1/32 001* 2 3/16 139 7 167 262 365 441
3/64 002* 2 1/4 053 140 228 331 7 1/4 168 263 366 442
1/16 003 102 2 5/16 141 7 1/2 169 264 367 443
5/64 004 2 3/8 036 142 229 332 7 3/4 170 265 368 444
3/32 005 103 2 7/16 143 8 171 266 369 445
1/8 006 104 2 1/2 037 144 230 333 8 1/4 172 267 370
5/32 007 105 2 9/16 145 8 1/2 173 268 371 446
3/16 008 106 201 2 5/8 038 146 231 334 8 3/4 174 269 372
7/32 009 107 2 11/16 147 9 175 270 373 447
1/4 010 108 202 2 3/4 039 148 232 335 9 1/4 175 271 374
5/16 011 109 203 2 13/16 149 9 1/2 177 272 375 448
3/8 012 110 204 2 7/8 040 150 233 336 9 3/4 178 273 376
7/16 013 111 205 309 3 041 151 234 337 10 274 377 449
1/2 014 112 206 310 3 1/8 235 338 10 1/2 275 378 450
9/16 015 113 207 311 3 1/4 042 152 236 339 11 276 379 451
5/8 016 114 208 312 3 3/8 237 340 11 1/2 277 380 452
11/16 017 115 209 313 3 1/2 043 153 238 341 12 278 381 453
3/4 018 116 210 314 3 5/8 239 342 12 1/2 454
13/16 019 117 211 315 3 3/4 044 154 240 343 13 279 382 455
7/8 020 118 212 316 3 7/8 241 344 13 1/2 456
15/16 021 119 213 317 4 045 155 242 345 14 280 383 457
1 022 120 214 318 4 1/8 243 346 14 1/2 458
11/16 023 121 215 319 4 1/4 046 156 244 347 15 281 384 459
11/8 024 122 216 320 4 3/8 245 348 15 1/2 460
13/16 025 123 217 321 4 1/2 047 157 246 349 425 16 282 385 461
11/4 026 124 218 322 4 5/8 247 350 426 16 1/2 462
15/16 027 125 219 323 4 3/4 048 158 248 351 427 17 283 386 463
13/8 028 126 220 324 4 7/8 249 352 428 17 1/2 464
17/16 127 221 5 049 159 250 353 429 18 284 387 465
11/2 029 128 222 325 5 1/8 251 354 430 18 1/2 466
19/16 129 5 1/4 050 160 252 355 431 19 388 467
15/8 030 130 223 326 5 3/8 253 356 432 19 1/2 468
1 11/16 131 5 1/2 161 254 357 433 20 389 469
13/4 031 132 224 327 5 5/8 255 358 434 21 390 470
1 13/16 133 5 3/4 162 256 359 435 22 391 471
17/8 032 134 225 328 5 7/8 257 360 436 23 392 472
1 15/16 135 6 163 258 361 437 24 393 473
2 033 136 226 329 6 1/4 164 259 362 438 25 394 474
2 1/16 137 6 1/2 165 260 363 439 26 395 475
2 1/8 034 138 227 330 6 3/4 166 261 364 440

*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. 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 have proven to be 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). Because of that. EMI Shielding has become a necessity in the electronics industry. Since there is 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. And so, there is an equally wide variety of thermal management options available.

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

1.4 Elastromeric Materials 126 Shielding Thermals

CORK / RUBBER

CORK & RUBBER PRODUCTS ARE INSTRUMENTAL IN METAL-TO-METAL JOINTS.

No allowance needs to be made for the side flow if a proper firmness material is selected. The compressibility of cork/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/rubber products can contain sponged materials that conform to and compensate for minor flange irregularities more easily. 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-rubber seals are more resistant to aging than traditional rubber compounds.

Cork/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
Cork and Rubber Elastomeric Materials
Cork & Rubber Composition
Property Test Method Typical Result Typical Result Typical Result Typical Result
Polymer Neoprene Neoprene Nitrile EPDM – Sponge
Density [ibs/ft3] ASTM D3676 35.7 37.5 39.9 31.5
Tensile Strength [lbs/in2] ASTM F152 240 355 253 135
Compression @ 100 psi ASTM F36 —- —- —- 35%
Compression @ 400 psi ASTM F36 45% 29% 40% —-
Recovery 80% 80% 82% 90%
Shore A Hardness ASTM D2240 63 60 to 80 60 to 70 54
Flexibility ASTM F147 3 max 3 max 3 max 3 max
Fluid Immersion ASTM F146
Oil 1 [70 hrs @ 212oF] -5 to +15% -10 to +8% -5 to +10% -10 to +10%
Oil 3 {70 hrs @ 212oF] +5 to +50% +5 o 15% —- +15 to +50%
Fuel A [22 hrs @ 75oF] 0 to +35% 0 to +15% —- 0 to +25%
Compression Set B ASTM D395
25% deflection, 22 hrs @ 158oF 55% max 65% max 60% max 90% max
Temperature Range oF -140 to +250 -140 to +250 -140 to +250 -140 to +250
Specification ASTM F104 F227000 M1 T F226000 M2 T F227000 M2 T F226000 M1 T
Specification MIL-G-12803 P2255B P2245A P2256A P2265A
Shelf Life 5 Years 5 Years 5 Years 5 Years
Cork & Nitrile Composition
Property Test Method Typical Result Typical Result Typical Result Typical Result
Polymer Nitrile Nitrile Nitrile Nitrile
Density [ibs/ft3] ASTM D3676 40.1 45.9 52.6 30.5
Tensile Strength [lbs/in2] ASTM F152 295 325 422 120
Compression @ 100 psi ASTM F36 25% —– —– 38%
Compression @ 400 psi ASTM F36 39% 33% 24%
Recovery 81% 82% 81% 90%
Shore A Hardness ASTM D2240 60 to 75 60 to 75 60 to 80 50
Flexibility ASTM F147 3 max 3 max 3 max 3 max
Fluid Immersion ASTM F146
Oil 1 [70 hrs @ 212oF] -5 to +10% -5 to +10% -5 to +10% 0 to +15%
Oil 3 {70 hrs @ 212oF] -2 to +15% -2 to +20% -2 to +15% +10 to +30%
Fuel A [22 hrs @ 75oF] -2 to +10% -2 to +10% -2 to +10% 0 to +15%
Compression Set B ASTM D395
Cork & Neoprene Composition
Property Test Method Typical Result Typical Result Typical Result Typical Result
Polymer Neoprene Neoprene Neoprene Neoprene
Density [ibs/ft3] ASTM D3676 35.6 48.4 53.1 48.4
Tensile Strength [lbs/in2] ASTM F152 218 336 400 336
Compression @ 100 psi ASTM F36 —– —– —–
Compression @ 400 psi ASTM F36 47% 25% 26% 32%
Recovery 81% 83% 80% 83%
Shore A Hardness ASTM D2240 61 65 to 75 60 to 80 65 to 75
Flexibility ASTM F147 3 max 3 max 3 max 2 max
Fluid Immersion ASTM F146
Oil 1 [70 hrs @ 212oF] -2 to +10% -2 to +20% -2 to +20% +2 to +10%
Oil 3 {70 hrs @ 212oF] +5 to +30% +15 to +50% +15 to +50% +10 to +50%
Fuel A [22 hrs @ 75oF] 0 to +15% 0 to +15% 0 to +15% 0 to +15%
Compression Set B ASTM D395
25% deflection, 22 hrs @ 158oF 60% max 60% max 55% max 60% max
Temperature Range oF -40 to +250 -40 to +250 -40 to +250 -40 to +250
Specification ASTM F104 —– F226000 M2 T F224000 M2 T F226000 M2 T
Specification MIL-G-12803 —– P2255A P2254A P2255A
Specification AMS-C-6183 TYP 1 CL 2 GR A TYP 1 CL 2 GR B TYP 1 CL 2 GR C TYP 1 CL 2 GR B
Shelf Life 5 Tears 5 Tears 5 Tears 5 Tears
Composition Cork
Property Typical Result
Density [ibs/ft3] ASTM D3676 15.8
Tensile Strength [lbs/in2] ASTM F152 125
Compression @ 100 psi ASTM F36 36%
Recovery 83%
Flexibility ASTM F147 5 max
Specification ASTM F104 F217000RT
Specification MIL-G-12803 P2128A
Specification HH-C-576B Cl 1 TY II
To learn more about cork/rubber material from The Gund Company or request a quote for your application, Contact Us Today!

FELT / WOOL

NATURAL WOOL FELT IS ONE OF THE OLDEST MAN-MADE 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 that is 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 common. Felt has special properties that allow it to be used for a wide variety of 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 considered to be 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 stories of Saint Clement and Saint Christopher relate that the men packed their sandals with wool to prevent blisters while fleeing from persecution. At the end of their journeys, the movement and sweat had turned the wool into felt socks.

Today’s pressed wool felt is made via an intricate process often referred to as “wet processing.” Fibers are worked together 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 layers that are then steamed, wetted, pressed, and hardened.

In the wet felting process, hot water is applied to layers of animal hairs. Repeated agitation and compression cause the fibers to hook together or weave together 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

Most fiber used in pressed felt is wool. Wool fibers have small barbs on them, which aid 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 will be more machinable, have better vibration absorption, and have 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
Elastomeric Materials
US Federal Specification C-F-206G
Type 1 Roll Felt SAE No. F-1 F-2 F-3 F-5 F-7 F-10 F-11
Classification No. 16R1 16R2 16R3 12R1 12R3 9R1 9R2
Wool Content % 95 90 85 95 80 95 87
Chlorothene Solubles % 2.5 2.5 2.5 2.5 4.0 2.5 3.0
Water Solubles % 2.5 2.5 3.0 2.5 4.0 2.5 2.5
Total Solubles % 3.0 4.0 4.5 3.0 7.0 3.0 4.5
Ash Content % 1.5 2.0 2.5 2.0 3.0 2.5 3.0
Tensile Strength psi 500 500 400 250 225 200 75
Slit Resistance psi 33 28 22 18 12 8 6
Width (inch) 60 60 60/72 60 72 72 72
Color White Pink Gray White Gray White Gray
Type1 Roll Felt SAE No. F-13 F-15N F-26N F-50 F-51 F-55
Classification No. 9R4 9R5 8R5 16R1X 16R3X 12R3X
Wool Content % 75 55 45 95 92 75
Chlorothene Solubles % 4.0 4.0 8.0 2.5 2.5 4.0
Water Solubles % 4.0 5.0 6.0 2.5 2.5 4.0
Total Solubles % 8.0 9.0 14.0 3.0 4.5 8.0
Ash Content % 3.5 4.0 5.0 1.5 2.5 3.0
Tensile Strength psi 75 75 75 500 300 200
Slit Resistance psi 2 2 2 33 22 12
72 72 72 72 60 60/72 72
Color Gray Gray Gray White Gray Gray or Black

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 with thicknesses ranging from .019” to 2”.

Polyester felt is fairly inexpensive and often made in comparable density and thickness to SAE-pressed wool felt. The maximum temperature of polyester felt is 300°F, compared to 200°F for SAE-pressed felts. This material is commonly used for filtration applications, gaskets, wipers, and padding in various industries. The density of polyester felt is commonly measured in ounces per sq. yd.

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

APPLICATIONS:

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

 

Elastomeric Materials from The Gund Company

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.

Elastomeric Materials