Dust-free Bulk Bag Discharger for Pneumatic Conveyors

BETHLEHEM, PA — A new Bulk Bag Discharger for operation in-line with pneumatic conveyor systems eliminates dust during untying, discharging, collapse, retying, and removal of bulk bags while increasing safety and promoting complete discharge of bag contents, according to Flexicon president, David Gill.

The design features a new bag-to-conveyor interface comprised of two sections, the uppermost of which contains a manual SPOUT-LOCK® clamp ring positioned atop a pneumatically actuated TELE-TUBE® telescoping tube, allowing dust-tight connections between the bag spout and hopper, as well as automatic tensioning of the bag as it empties to promote flow and evacuation.

The lower section is comprised of a small surge hopper that directs material into the throat of a variable speed rotary air lock feeder for volumetric or gravimetric metering into positive- or negative-pressure pneumatic conveyor lines.

The telescoping tube raises the clamp ring assembly that seals the clean side of the bag spout to the clean side of the telescoping tube, then lowers until the bag spout is pulled taut. Once the spout is untied, the telescoping assembly exerts continual downward tension on the spout, elongating the bag as it empties.

The high-integrity, dust-tight seal between bag spout and clamp ring allows full-open discharge from bag spouts of all popular diameters, eliminating the need for iris valves commonly employed to lessen dust escape inherent with bag spouts hanging loosely in hopper intake chutes.

A BAG-VAC® dust collector integral to the dust-tight system creates negative pressure to collapse empty bags prior to retying and disconnection, eliminating dust emitted during manual flattening of empty bags.

An optional POWER-CINCHER® pneumatically actuated flow control valve allows retying of partially empty bags. Unlike devices using opposing bars to pinch the spout from two sides, the
Flexicon design employs a series of curved, articulated stainless steel rods to cinch the spout concentrically on a horizontal axis for easy tie offs, and vertically in a tight zigzag pattern to prevent leakage of fine powders.

The discharger is also equipped with optional FLOW-FLEXER® bag activators that raise and lower opposite bottom edges of the bag at timed intervals, loosening compacted materials and promoting material flow into the bag discharge spout. As the bag lightens, the stroke of the bag activators increases, raising the bag into a steep "V" shape,

eliminating dead spots for total evacuation of material with no manual intervention.

BFC Series dischargers are characterized by a cantilevered I-beam with electric hoist and trolley to raise and position bulk bags without the aid of a forklift. Also offered are BFF Series dischargers equipped with top-mounted receiving cups and removable bag-lifting frames for forklift loading of bulk bags at low cost.

All are fitted as standard with new Z-CLIPTM strap holders* for rapid, secure insertion and removal of bag straps, and are available with integrated scale systems for loss-of-weight batching directly from bulk bags.

"This new generation discharger overcomes limitations inherent with conventional designs, and unlike Flexicon's previous discharger, it is based on advances that are patented or patent pending," says Gill.

Construction is of carbon steel with durable industrial finish, or stainless steel finished to industrial food, dairy or pharmaceutical standards.

*Patent(s) granted and/or pending.