We are all aware the importance of rubber as an indispensable material that has use in virtually every kind of industrial application. Rubber's unique property of resilience makes it extremely suitable for critical applications involving sealing, shock absorption and fluid transportation. Out of various rubber processing methods, extrusion takes its place as a popular choice. One of the reasons being the neat and uniform way through which extruded rubber profiles are produced. Typical examples of rubber extruded profiles include continuous sheet, tubing, seals, gasket profiles and weathering stripping.

Rubber Extrusions can be of three types Sponge rubber extrusion, solid rubber extrusion and cellular rubber extrusion. Features of the rubber extruded profiles that makes them very popular include:

• Resistance to ozone
• Heat and cold resistance
• Flex-crack resistance

Important Considerations in Rubber Extrusions
When thinking of rubber extrusion, consideration is to be given regarding the physical and mechanical properties of the material. Question is to be asked is regarding its appropriateness for the environment where it will be used. Typical Properties like permeability, aging, tensile strength, hardness, flexibility and speed of recovery from deflection tends to vary with different materials and this needs to be carefully weighed against the respective benefits or weaknesses.

Applications of Extruded Rubber Products
Extruded rubber products are used in numerous industries. Some of the major industries are shown here.

• Building Industry
  Profiles in sponge and solid forms are a favourite with the building industries. Other applications include Rubber seals for doors and windows.
  
  
• Construction Industry
  Applications include expansion joints for roads, bridges and runways.
  
  
• Automotive Industry
  A wide range of rubber extruded profiles are used in automotive applications. Typical shapes like continuous length or jointed frames for use in weather strips and underhood applications. Some of the most popular uses include :-
  • Sponge Door Weather Strips
  • PU Coated or Flocked Run-Channels
  • Solid Windscreen Rubbers
  • Tubing and Protectors
  
  
  
  
  
• Railways
  Profiles for doors, windows and gates.
  
  
• Medical Industry
  Rubber thread as in catheters.
  
  
• Specialised Application
  A very special application of extruded products is in providing intumescent solutions for positive pressure code requirements.

Materials for Extruded Rubber Profiles
There are many types of rubber that are suitable for extrusion process some of them are listed here:

• EPDM Profile
• Silicone Extruded Profiles
• Thermoplastic Elastomer
• Acrylonitrile-butadiene (nitrile) (NBR)
• Styro-Butadiene( SBR)
• Neoprene
• Nitrile
• Natural rubber
• Butyl
• Hypalon
• Timprene

Comparing the properties of Rubber extrusion material
The following table takes a hard look at physical and chemical properties of rubber material used in the extrusion process.

Material	EPDM	Neoprene	SBR	SBR	Silicone
Durometer Range (Shore A)	45-90	45-90	45-95	50-80	45-90
Tensile Range (P.S.I)	500-2500	400-4000	500-3000	500-3000	200-1500
Elongation (max.%)	600	75-600	600	600	700
Compression Set	Good	Good	Good	Good	Good
Resistance to abrasion	Good	Good-Excellent	Excellent	Excellent	Poor-Fair
Tear Resistance	Fair	Good	Excellent	Fair	Poor
Solvent Resistance	Poor	Poor	Good	Poor	Poor
Oil Resistance	Poor	Fair	Fair	Poor	Poor-Fair
Aging Weather - Sunlight	Excellent	Good	Good	Poor	Excellent
Adhesion to Metals	Fair-Good	Fair-Good	Good-Excellent	Excellent	Good
Resilience - Rebound	Good	Good	Good	Good	Good

Buyers Zone As a smart buyer dealing in rubber extruded profiles you need to ask the following important questions before venturing to procure extruded profiles. Whether the properties both physical and mechanical of the desired material are conducive to the environment, where it will be put to use. Properties like aging, tensile strength, hardness, flexibility, permeability and speed of recovery from the deflection shows a tendency to vary in different materials, so there is a need, that they be weighed against the respective benefits/weaknesses that will result from using such materials.

Shapes of Rubber Extruded Products
Coming to the shapes of rubber extruded profiles a variety of shapes are possible with distinctive features. Some of the popular shapes are described here:

Applications include Wiper, Seal, Filler Strip, or even as Edging. Profiles can be in cut pieces, coil form, long straight lengths, form-cured lengths etc.	Angle Extrusion Applications include Wiper, Seal, Filler Strip, or even as Edging. Profiles can be in cut pieces, coil form, long straight lengths, form-cured lengths etc. Bumper Strip Profiles can be available in the form of coil, long straight lengths, form-cured lengths, to cut pieces also.	Generally used as a Filler Strip, Seal, or even as a Glazing Seal. Profiles are easily available in the form of coil, long straight lengths, cut pieces to even form-cured lengths.