An insertion magmeter from George Fischer solved a problem that Crown City Plating Co was experiencing in its chrome effluent neutralization waste line. The El Monte, CA company manufactures electroless and electroplate on metal and plastic, injection molding, painting, decorating, and subassembly.

Chrome must be neutralized with various reagents before discharge to city sewers. The flow measurement in the neutralization process dictates the proper amount of neutralizing reagents to be injected; using more chemicals than required would cost the company excess in neutralizing chemicals and sewage discharge fees. (Shown left, the 2536 paddlewheel sensor with particles on pin and rotor.)

The flow measuring device that had been used in this application, a Signet Model 2536 paddlewheel sensor, was being cleaned weekly because it was getting clogged with metal shavings and coated from the process liquid. Initially, the 2536 output would be okay after each cleaning, but it would soon become sluggish, and within a week would output erroneous readings. Maintenance time to shut the line down, pull the sensor out of the line, clean it, and reinstall was approximately 30 minutes per week.

To solve the issue of the continuously dirty paddlewheel, Crown City installed the new Signet Model 2551 magmeter. Installation was simple and easy because the magmeter went directly into the existing paddlewheel fitting. The 2551 performed exceptionally well and was not cleaned for at least one month. After a month, the sensor was removed and a coating could be seen on the metal electrodes, grounding ring, and plastic body. Following cleaning, the sensor was reinstalled and continued to provide excellent performance. Crown City Plating has been pleased with the reduced maintenance time and costs it has experienced with the 2551. (Shown right, the Signet 2551 Magmeter after one month installed in effluent line; note dirty brown color of sensor tip compared to sensor color below the o-ring.)