Rosemount 5300 and 3300 Series extreme temperature and pressure probes are designed to prevent leakage and perform reliably when exposed to extreme process conditions for extended periods of time. Materials are selected to avoid stress fractures commonly induced by changes in temperature and pressure conditions. For example, aluminum oxide ceramic insulators provide electrical feedthrough for microwave signals while acting as an impermeable barrier to the temperature and pressure conditions in the tank.

The design of the probe provides multiple layers of protection. The seal includes a temperature and pressure barrier in a flexible assembly to handle forces induced by probe movement and temperature variations. A second brazed hermetic, gas-tight seal provides another layer of protection and the entire assembly is welded into a stainless steel sleeve for total robustness. The extreme range of probes handle temperatures from -320 ºF (-196 ºC) up to 752 F (400°C) and pressures up to 5000 psi (345 Bar). They are available for the single lead probes and the coaxial lead probe.

The hermetic seal is isolated from the process and temperature shocks. Pressure and outside forces on the probe will not affect the integrity of the seal.

A flexible probe load and locking system compensates for stress from thermal expansion and lateral and vertical forces. It also protects and fastens the ceramics.

The ceramic insulators and graphite gaskets on the temperature and pressure seal provide a robust thermal and mechanical barrier as well as offering chemical resistance.