Red Arrow dumps capacitance for radar level technology 10 December 2012

Red Arrow Products has replaced what it sees as unreliable capacitance-based level measurement devices with guided wave radar transmitters from Emerson Process Management.

Barry Schardt, equipment manager and electrical engineer at the smoke condensates and flavourings processing plant in Manitowoc, Wisconsin, USA, says that, as a result, the firm has been able to schedule its maintenance around probe cleaning – so reducing costs and increasing throughput by avoiding unplanned shutdowns.

"In the past, occasional unplanned shutdowns, due to probe failures or coating issues, would upset our process – reducing product throughput and increasing energy use," states Schardt.

"Since we installed Emerson's guided wave radar transmitters, about one year ago, we have not had premature shutdowns during a production run due to level probe failure."

Schardt explains that Red Arrow's wood oil is held in a 1.5-meter tall collection tank that must maintain a constant level in an evaporation process. Although this technology usually performs well in applications that operate at high temperatures and with viscous/sticky products, coatings were causing unreliable level problems.

He makes the point that this is a particularly challenging level application, as the tank operates under vacuum and the measurement device is subject to vapours and mist.

Red Arrow also had concerns about the problem of build-up of a sticky tar-like substance on the probe in the tank, which could cause signal degradation.

Hence the upgrade to a Rosemount 5300 GWR with a single rigid probe and signal quality metrics (SQM). GWR devices are unaffected by changes in pressure and vapour space conditions, and SQM provides diagnostic information that relates directly to the coating on the probe and to changing surface conditions.

Brian Tinham

Related Companies
Emerson Process Management

This material is protected by MA Business copyright
See Terms and Conditions.
One-off usage is permitted but bulk copying is not.
For multiple copies contact the sales team.