Rubber Profile Extrusion is accomplished by forcing uncured rubber through a die, under heat and pressure, to form a part with a uniform cross section. This uncured rubber is then run through a heating unit to initiate the chemical cross linking reaction that causes the rubber to cure. This heating can be accomplished by anything from hot air to microwave to a salt bath. Sponge rubber can be produced by combining the raw rubber with a compound that gives off gas in the presence of heat. The expanding gas gives sponge rubber it's cellular nature. Rubber extrusions can be produced with multiple types of rubber in the same profile to vary the characteristics of the different parts of the profile.
 

Process Characteristics
Tool Costs - low Part costs - medium Production rate - high Unifrom cross section of parts Multiple materials / durometers are possible in the same part Short lead times to production
Examples
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