BFF Series Bulk Bag Unloader for Pneumatic Conveyors

Eliminates dust during untying, discharging, collapse, retying, and removal of bulk bags while increasing safety and promoting complete discharge of bag contents

Flexicon's BFF Series Bulk Bag Unloader 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.

The lower section is comprised of a small surge hopper that directs material into a pneumatic pick-up adapter with four conveying line connections. The hopper can also be equipped with a variable speed rotary air lock feeder for volumetric or gravimetric metering into pneumatic conveyor lines, or with a Flexicon flexible screw conveyor, or a universal flanged hopper outlet for connection to other conveyors or process equipment.

Based on advances that are patented or patent pending, the unloader design features a revolutionary bag-to-conveyor interface comprised of two sections, the uppermost of which contains a 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 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.

The dust-tight system can be vented to an optional BAG-VAC® dust collector that collapses empty bags dust-free prior to retying and disconnection, eliminating dust caused by manual flattening.

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 unloader 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.

BFF Series unloaders (shown) are characterized by top-mounted receiving cups and removable bag-lifting frames for forklift loading of bulk bags at low cost. Also offered are BFC Series unloaders having a cantilevered I-beam with electric hoist and trolley to raise and position bulk bags without the aid of a forklift. Both Series of unloaders are fitted as standard with patented Z-CLIP™ 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.

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.
BFF Series Bulk Bag Unloader for Pneumatic Conveyors
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A bag-lifting frame allows placement and removal of bulk bags using a forklift. Bulk material is discharged from the bag into a small surge hopper configured with a pneumatic pick-up adapter having four conveying line connections.