Probe Properties

All our fibre optic cables and probes can be modified to customers request. Most materials we use in our fibre optic assemblies can be replaced with others to improve specific chemical or thermal resistance, to enhance vacuum or pressure properties.

Please contact our fibre design engineers with your specific request.

In the following information, some of the most essential technical parameters are listed for our standard materials.

 

Thermal resistance

The thermal resistance of a fibre optic assembly depends on the following components:

1. Fibre, the standard fibre design is a silica/silica fibre and has a polyimide buffer, covering a wide thermal range -190 - 400 °C. For higher temperatures aluminum coated (upto 500°C) or gold coated (upto 750°C) fibers are recommended.
2. Sleeving, the standard sleeving is PVC based and has a small temperature range (-20°C - 65°C). For higher temperatures, a flexible metal sleeving (-ME) with silicone inner tubing is recommended (upto 250°C) or stainless steel tubing (not flexible, upto 750°C).
3. Probe tips, connectors and ferrules are as standard made of metal and have a wide temperature range. For special plastics such as PVC, PEEK and Teflon, a limited temperature range is applicable.
4. Bonding epoxy, the standard epoxy used is a heat curing bonding epoxy with a temperature range of -60°C - 175°C. The curing temperature is standard 100 °C, for high temperature ranges (order code -HT), the curing temperature is 200°C. Sometimes UV curing epoxies are used.

Technical Details

Temperature Range	Fibre	Sleeving	Probe End	Epoxy
-20 - 65°C	Standard Polymide	Standard PVC	Standard Metal/PVC/ PEEK/PTFE	Standard
-30 - 100°C	Standard Polymide	Metal (ME) or Silicon (MS)	Standard Metal/PEEK/PTFE	Standard
-60 - 200°C (HT)	Standard Polymide	Metal (ME) or Silicon (MS)	Standard Metal/PEEK/PTFE	High temperature curing epoxy
-60 - 400°C	Standard Polymide	Metal (ME) or SS tubing	Metal	Special Polimide epoxy or ceramic
-60 - 500°C	Aluminium Coated	SS tubing or none	Metal	Direct bonding
-60 - 750°C	Gold Coated	SS tubing or none	Metal	Direct bonding

Chemical resistance

The chemical resistance of a fibre optic assembly depends on the following components:

1. Fibre, the standard fibre design is a silica/silica fibre and has a polyimide buffer, which normally will not be in contact with the sample; the quartz core provides good resistance against most solvents.
2. Sleeving, the standard sleeving is PVC based and has a relatively good chemical resistance. The ME chrome plated brass sleeving also has a good chemical resistance, but is not waterproof. The Silicone metal sleeving (MS) is recommended for waterproof environments, biomedical applications, etc. The PEEK and PTFE sleeving have the best chemical resistance.
3. Probe tips, connectors and ferrules are as standard made of stainless steel and are not very well suited to corrosive environments. For most corrosive environments, PEEK, PTFE or Hastelloy® are recommended.
4. Bonding epoxy, the standard epoxy is resistant to water, inorganic acids, salts, alkalis, many aggressive organic solvents, most petrochemical products and an extended range of organic and inorganic environments.

The table below gives a good summary for the chemical resistance for our standard materials.

The table has been drawn up on the basis of relevant sources in accordance with the state of the art; no claim to completeness.

The data constitutes recommendations only, for which no liability can be accepted.

Please contact us if you have any doubt about the materials to use for your application.

Technical Details

Chemical Environment	Fibre		Sleeving		Probe End		Epoxy
Acids weak	Silica/Silica	+	ME MS PEEK PTFE	± + + +	SS PEEK PTFE Hastelloy®	- + + +	+
Acids strong	Silica/Silica	+	ME MS PEEK PTFE	- ± + ±	SS PEEK PTFE Hastelloy®	- + + +	±
Bases weak	Silica/Silica	+	ME MS PEEK PTFE	+ + + +	SS PEEK PTFE Hastelloy®	+ + + +	+
Bases strong	Silica/Silica	+	ME MS PEEK PTFE	+ + + +	SS PEEK PTFE Hastelloy®	+ + + +	+
Aromatic carbons	Silica/Silica	+	ME MS PEEK PTFE	+ + + +	SS PEEK PTFE Hastelloy®	+ + + +	+
Alcohols	Silica/Silica	+	ME MS PEEK PTFE	+ ± + +	SS PEEK PTFE Hastelloy®	+ + + +	+
Ketons/Ethers	Silica/Silica	+	ME MS PEEK PTFE	+ - + -	SS PEEK PTFE Hastelloy®	+ + + ±	±