Abstract: A secondary seal assembly is used with a process instrument including a probe assembly and an electric housing assembly. The probe assembly includes an adaptor receivable in an opening of a process vessel, a probe extending through the adaptor into the process vessel, and a primary seal between the probe and the adaptor. A probe terminal provides an electrical connection between the probe and the electric housing assembly. The secondary seal comprises an elongate extension housing adapted to be mechanically connected at one end to the adaptor and at another end to the electric housing assembly. A shaft insert is received in the extension housing having a terminal at each of opposite ends, a first terminal for providing an electrical connection to the electric housing assembly and a second terminal for providing an electrical connection to the probe terminal. A seal between the shaft insert and the extension housing provides a secondary seal to the process vessel.

Abstract: An improved mounting arrangement is shown for a magnetostrictive level sensing instrument for sensing level of a process fluid in a process vessel. The process vessel includes an opening into a storage space in the vessel. The improvement includes an elongate tube having a closed end and an opposite open end. A process fitting receives the open end of the outer tube, the process fitting being adapted to be received in the vessel opening, in use, whereby the process fitting and the elongate tube seal the vessel opening. A magnetostrictive wire assembly is removably received in the elongate tube through the open end for operatively sensing position of a magnetic float captured on the elongate tube and floating atop the fluid in the vessel. A housing is mounted to the adaptor fitting and supports the wire assembly when the wire assembly is received in the tube.