Leaded Glass fiber is capable of operation up to 900°F (482°C). Silica fiber has a much higher heat tolerance, but the buffer used in the construction of these fibers makes the resulting heat tolerance much lower (around 400 F)
Beyond 900F the fiber slowly starts to soften and will fail in a relatively short time. However, adhesives and bonding agents used to assemble the light guide have even lower tolerance to heat. Depending on material(s) used, the limit for high temperature applications is 600°F (315°C) (constant exposure), using a typical high temperature designed epoxy.
If special assembly techniques are used, standard borosilicate fiber can be used in component parts for high temperature applications up to 900°F. These special techniques may include the use ceramic-based bonding agents or epoxy-less assembly techniques.
Because these techniques and materials are expensive and/or difficult to use, only one end is designed for high temperature operation. If your application requires protection at both ends, contact us.
If plastic (PMMA) fiber is used, maximum exposure temperature is 158°F (70°C). This is the melting point of PMMA fiber.
Temperature references relate to ambient conditions and do not factor in heat generated by light absorption. For instance, a borosilicate glass fiber component, in a 70°F ambient environment, plugged into a 150W quartz-Halogen lightsource, may still fail (melt at the input) if an IR mirror is not used. The epoxy absorbs light and IR energy, converting it to heat energy, which increases the input temperature . This temperature may increase to the point where the epoxy and/or the glass melts! So it’s very important to keep the input tip clean, free from foreign debris, which can absorb energy, converting it to heat.
Standard Fiberoptics Technology light guides are constructed for operation at 350°F. Upon request, 600°F epoxy may be substituted at no extra charge. Or, 900°F degree construction is available on special order.
Our silica fiber cannot be assembled using our 900°F degree construction and therefore is limited to 600 °F operation.
Borosilicate fiber components can withstand up to 900°F temperatures if manufactured using special assembly techniques.