November 10, 2014 - Axiom Analytical announced FPT-850LT Cryogenic Near-Infrared Transmission Probe. The probe is for long-term service at extremely low temperatures, in such applications as Liquefied Natural Gas (LNG) processing. The low temperature probe has been developed to provide maximum long term reliability under the extreme conditions of thermal shock and aggressive chemistries encountered in many on-line process applications. The probe design has two key elements. The first is a sealing technique involving a direct sapphire to metal welded pressure seal.
A high degree of chemical resistance is assured by the fact that the only materials in contact with the process are sapphire, high nickel alloys, and a thin layer of PTFE. The compliance required to withstand extreme temperatures is provided by the high nickel alloy seal which is compressed at high pressure prior to welding. This approach eliminates fatigue and stress failures common with brazed seals as well as the limited lifetime characteristic of elastomeric seals. The second key element of the FPT-850 design is the elimination of optical fibers within the probe. This insures optical stability and long term reliability.
The elimination of both internal optical fibers and elastomeric seals provides for reliable long term operation at temperatures as high as to 400ºC.