With pH measurements in chemical processes, a combined pH/Reference electrode is usually mounted in a by-pass flow fitting, a flanged immersion fitting or an on-line retractable fitting. Applications for the PR20 retractable fitting can be found in all processes where the pH sensor should be removed without interrupting its continuity (e.g. pulp slurries, pressurised systems).

The Yokogawa design ensures the safe retraction of the electrode from the process without a shut-down. The optional adapters make selection of a suitable constructioneasy.

Both flanged and tapered connections are available in DIN or ANSI versions. The standardised connection (11/4 inch BSPP) is used for weld-in sockets as well. When inserted, the probe can be locked at any position (between the minimum and maximum) with a locking ring. In addition tothat optional flush ports make cleaning without complete disassembly possible.
The choice between stainless steel and titanium as construction materials, make use in many applications possible.

Yokogawa recommends to use the combined electrodes:
SC21-AAP26, SC21-AGP26, SC21-ALP26, SC29-PTP29

For safety reasons Yokogawa recommends to use a flanged ball-valve