Smart Feeder Controls Bulk Solids at High Feedrates

At the 1999 Powder and Bulk Solids Show, (Rosemount, IL, May 10-12), K-Tron America showed its Smart Flowfeeder configured as a low-cost, low-maintenance, and compact alternative to the large loss-in-weight feeder for use in applications requiring high flowrates.

The Smart Flowfeeder offers processors superior accuracy and repeatability over conventional impact and coriolis flowmeters. It can be used as a feeder, meter or batcher. As a lower-cost alternative to loss-in-weight feeders in high rate applications, it saves considerable headroom. K-Tron showed a complete engineered package with Smart Flowfeeder, rotary valve, vacuum conveyor and controls.

The benefits to processors include no moving parts directly exposed to the material, no interruption of flow, little or no field calibration, low maintenance, superior accuracy and lower cost than a high rate loss-in-weight feeder.

The Smart Flowfeeder's operating principle is like a weigh belt feeder at a 60° angle. In a weigh belt, material is transported at constant speed over a weighing platform. With both speed and weight known, flowrate can be determined. In a similar manner, and unlike other approaches to flowmeter design, the Smart Flowfeeder employs two separate Smart Force Transducer IIs (SFT IIs) to sense the material flow's weight and speed.

A bypass flap is built into the flowmeter inlet. This allows the bulk material flow to be diverted into a separate internal channel for re-taring, without interrupting the process. During this diversion the new tare is taken to establish a new zero-compensation for any dust or material build-up without interruption to the process. Re-taring can be done manually or by programming the controller to periodically perform the operation.

The Smart Flowfeeder is available in two capacities: Model SFM275 for flows from 3,300 lb/h (1,500 kg/h) to 220,000 lb/h (100,000 kg/hr), and Model SFM350 from 11,000 lb/h (5,000 kg/h) to 660,000 lb/h (300,000 kg/h). Short and long term accuracy of <+1% can be achieved without calibration. A simple field calibration procedure is available which can increase accuracy further. Both models are rated IP65 (NEMA 4) with all stainless steel construction DIN 1.4301 (AISI 304). Two access doors are provided for easy cleaning.

Contact K-Tron America, Routes 55 and 553, Pitman, NJ 08071. Call +1 609-589-0500. Fax +1 609-589-8113.