BULK HANDLING EQUIPMENT & SYSTEMS

CASE HISTORIES

CASE HISTORIES

 
 

Transferring Multiple Bulk Materials Without Cross Contamination

By David Boger, Vice President - Global Business Development

To increase sales, food processors often broaden their product lines, increasing the frequency of changeovers. Toll processors and contract packagers are also faced with increased changeovers as the number and diversity of food products they handle expands. This places greater responsibility on plant management to prevent cross contamination, while minimizing the non-productive downtime that cleaning and sanitizing incurs.

Conveying multiple runs of food materials calls for equipment that prevents build-up during operation, and allows potential contaminants to be removed rapidly afterwards.

A Flexicon® flexible screw conveyor excels in this regard because the smooth inner screw is the only moving part contacting material; its lower end has no bearing or seal, and its upper end is driven beyond the point of discharge, preventing material contact with the motor bearing or seal.

It also lacks internal seals, crevices or joints that can trap particles or breed contamination. Reversing the screw rotation will evacuate residual material and allow the smooth interior surfaces to be flushed with air, water, steam or cleaning solution.

Transferring Multiple Bulk Materials Without Cross Contamination
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The screw of this Flexicon conveyor is driven beyond the point of material discharge, preventing material contact with seals and bearings, minimizing associated cleaning time during changeovers.

Transferring Multiple Bulk Materials Without Cross Contamination
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The intake end of this Flexicon flexible screw conveyor lacks seals or bearings that would otherwise collect material and increase cleaning difficulty.

Transferring Multiple Bulk Materials Without Cross Contamination
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Flexicon flexible screws are readily disconnected from the motor drive and removed through the lower end cap of the conveyor tube, allowing inspection and sanitizing of the screw and flushing of the tube with cleaning solution or steam.

Transferring Multiple Bulk Materials Without Cross Contamination
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Depending on material flow characteristics, this Flexicon High Flow Hopper eliminates or reduces residual material at the conclusion of production runs, reducing changeover times.


As with Flexicon flexible screw conveyors, FLEXI-DISC® tubular cable conveying systems are driven beyond the point of final discharge, preventing material contact with seals or bearings. By evacuating material at the end of a production run, these conveying systems can eliminate waste and residual material, minimizing downtime for cleaning and sanitizing.

Transferring Multiple Bulk Materials Without Cross Contamination
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In its most basic form, this FLEXI-DISC® conveyor illustrates how the cable-disc assembly is driven beyond the point of discharge, preventing material contact with seals and bearings at both the upper motor drive and the lower cable tensioner.

Transferring Multiple Bulk Materials Without Cross Contamination
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Tubular cable conveying systems can be configured with multiple (shown) or single discharges. In either case, the cable-disc assembly is driven beyond the point of final discharge, which in this case is an intermediate discharge.


FLEXI-DISC cable is offered in stainless steel, and is available polymer-coated. Straight tubing, elbows and couplings are offered in 304 or 316 stainless steel finished to sanitary standards, while material inlets, outlets and ancillary metallic components are of 304 or 316 stainless steel with continuous welds ground and polished.

Transferring Multiple Bulk Materials Without Cross Contamination
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Discs of high-strength polymers on 304/316 stainless steel cable glide within smooth stainless steel tubing, evacuating material and allowing thorough cleaning.


Wet or dry cleaning accessories can be attached to the FLEXI-DISC cable to minimize downtime between changeovers, while Clean-In-Place (CIP) accessories allow rapid, automated and thorough sanitizing of the system.

Transferring Multiple Bulk Materials Without Cross Contamination
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Wet or dry cleaning accessories (shown) can be readily attached to the cable during changeovers.


With bulk bag unloaders, the most critical aspects relating to ease of changeover are the ability of the unloader to evacuate material and dust from the bag, and the cleanliness of the bag-to-equipment interface.

Transferring Multiple Bulk Materials Without Cross Contamination
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BULK-OUT® Sanitary Bulk Bag Weigh Batch Unloading System with integral flexible screw conveyor, manual dumping station and BAG-VAC® dust collector.


The interface should be designed to connect the clean side of the bag spout to the clean side of the equipment and allow rapid connections/disconnections. It should also provide unobstructed access to internal surfaces, which should be smooth and devoid of seams, allowing rapid cleaning, sanitizing and visual inspection of all material contact surfaces.

Transferring Multiple Bulk Materials Without Cross Contamination
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It is also critical to evacuate bags of residual material — especially non-free-flowing ingredients trapped in corners or dead spots of the bag — by employing flow promotion devices. In the case of BULK-OUT® dischargers, FLOW-FLEXER® bag activation devices raise and lower opposite bottom edges of the bag on timed cycles, ultimately raising the bottom of the bag into a steep V-shape, as the top of the bag is stretched upwards, minimizing waste and the amount of material that must be cleaned.

Transferring Multiple Bulk Materials Without Cross Contamination
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Empty bag has been raised into a steep V-shape by FLOW-FLEXER® bag activators, and stretched upwards by POP-TOP™ bag extension devices (BFF forklift load models) or raised by a hoist that travels on a cantilevered I-beam (BFC models).


Because flattening of empty bags can send clouds of dust into the plant, endanger workers and require clean-up, the discharging system should be air-tight and vented to a dust collector that collapses empty bags prior to tie-off of the spout and removal of the bag from the unloader.

Transferring Multiple Bulk Materials Without Cross Contamination
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Transferring Multiple Bulk Materials Without Cross Contamination
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BAG-VAC® dust collector draws displaced air and dust from sealed unloading system during discharge, and flattens empty bags prior to tie-off and disconnection, eliminating dust generated by manual flattening of empty bags.

Transferring Multiple Bulk Materials Without Cross Contamination
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If the unloader is equipped with a surge hopper, its design should promote evacuation of the specific material being unloaded, minimizing the need to clean it during changeovers.

Transferring Multiple Bulk Materials Without Cross Contamination
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High flow hopper designs with continuous, polished weld seams eliminate dead spots, reducing changeover times.


With regard to conveying technologies offered by Flexicon, flexible screw conveyors and FLEXI-DISC® tubular cable conveyors allow the most rapid and thorough changeovers.

Flexicon 3-A Certified and USDA Accepted models are especially suited to operations that require frequent changeovers because they are not only finished to sanitary standards, but engineered for rapid changeovers from the onset. Mobile sanitary models offer the added benefit of handling multiple tasks within the plant, and can be rolled to wash-down stations.

Transferring Multiple Bulk Materials Without Cross Contamination
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In-plant mobility enables 3-A Dairy certified flexible screw conveyor to be rolled to wash-down stations for sanitizing during changeovers.

Transferring Multiple Bulk Materials Without Cross Contamination
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Sanitary, mobile flexible screw conveyor from Flexicon tilts down for maneuvering through tight spots, and allows easy removal of the screw for sanitizing.

Transferring Multiple Bulk Materials Without Cross Contamination
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Mobile sanitary Tilt-Down Conveyors can be maneuvered through narrow isles to serve multiple functions, and be rolled to dedicated wash-down stations. Tubular frame members (shown) dry faster than square members that allow water to puddle following wash-down.


For the addition of minor ingredients, using a Bag Dumping System with a glove box, bag compactor and enclosed flexible screw conveyor isolates the added bulk material from the operator and the plant environment throughout the opening, dumping, compaction of bags, and the conveying of the added material downstream.

Bags are staged on a stainless steel tabletop and then transferred through a plastic strip curtain into the dumping enclosure. The dust collector maintains negative pressure within the enclosure, preventing the escape of dust through the curtain during bag opening and dumping activities.

A bag infeed chute through the sidewall of the enclosure allows the operator to pass empty bags directly into the bag compactor, causing dust generated from compaction as well as dumping activities to be drawn onto the system's two filter cartridges.

An automatic reverse-pulse filter cleaning system releases short blasts of compressed air inside the filters at timed intervals causing dust build-up on the outer surfaces to fall into the hopper, conserving useable product. Filters are readily accessed by removing the interior baffle, and replaced rapidly using quick-disconnect fittings.

The compactor employs a large pneumatic air cylinder to compress bags into a removable bin that accommodates 50 to 80 bags, substantially reducing the volume of waste, containing dust and minimizing the time for operators to empty the compactor.

The main waste access door, and a flapper door within the bag infeed chute, are equipped with safety interlocks that prevent operation of the compactor unless both doors are closed.

The hopper discharges into an enclosed Flexicon flexible screw conveyor for dust-free transfer of the material to downstream processing.

Transferring Multiple Bulk Materials Without Cross Contamination
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Dust generated from bag opening, dumping and compaction is isolated from the operator and plant environment by means of a glove box, dust collector and integral bag compactor with sealed infeed chute. An enclosed Flexicon flexible screw conveyor transfers material downstream at any angle, dust-free.


All-stainless-steel bag dump stations for pneumatic conveying systems collect dust created during manual dumping of added ingredients from bags, boxes, drums or other containers and allow rapid, tool-free wash-down.

Optional rocker arms support the hood assembly above the hopper rim, eliminating the need for operators to lift and remove the hood during cleaning and inspection.

A stainless rotary airlock valve at the hopper discharge is equipped with integral support rails that allow the rotor assembly to separate from the valve body for sanitizing of all material contact surfaces, and to close securely in seconds, also without tools.

Here again, a high velocity vacuum fan draws airborne dust from the operator's atmosphere onto two cartridge filters. Automatic reverse-pulse filter cleaning allows continuous, efficient operation; timer activated solenoid valves release short blasts of compressed plant air inside cartridge filters causing dust build-up on the outer filter surfaces to fall into the hopper.

Filters are accessed easily by removing the interior baffle, and replaced rapidly using quick-disconnect fittings.

The all-stainless unit is also offered with an integral flexible screw conveyor, or with universal hopper discharge flange for connection to downstream process equipment, and is available mounted on frames with casters for in-plant mobility.

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Optional rocker arms allow the hood assembly to separate from the hopper rim, allowing thorough, rapid wash down.


For processes that require the addition of materials arriving in boxes, containers, or drums, TIP-TITE® dumpers are engineered to lift and discharge the contents dust-free, protecting the plant environment and avoiding contamination.

Sanitary models are available for boxes, drums and other containers. In each case the container is loaded onto a platform that raises it and seats it against a discharge hood. Hydraulic cylinders then pivot the platform-hood assembly and tip to a 45, 60, or 90 degree angle with a motion-dampening feature. A slide gate allows controlled material discharge.

Enclosed receiving hoppers can be configured for mechanical or pneumatic conveying or for connection to other downstream equipment. Optional vibration enhancements are available for non-free-flowing materials.

Transferring Multiple Bulk Materials Without Cross Contamination
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Transferring Multiple Bulk Materials Without Cross Contamination
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TIP-TITE® Drum Dumper, with sanitary all-stainless contact elements, seals drum rim against a discharge cone, tips the drum, mates the cone against a gasketed connection, and discharges bulk material dust-free through a slide gate valve.

Transferring Multiple Bulk Materials Without Cross Contamination
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TIP-TITE® Box-Container Dumper creates dust-tight seal between boxes and containment hood, pivots the container to 45, 60 or 90 degrees beyond horizontal, and discharges bulk material through a chute at controlled rates. Accommodates boxes from 36 in. to 48 in. (915 mm to 1220 mm) on a side and 39 in. to 44 in. (990 mm to 1117 mm) high.

Transferring Multiple Bulk Materials Without Cross Contamination
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TIP-TITE® High Lift Drum Dumper seals drum rim against a discharge cone, raises and tips the drum, mates the cone against a gasketed connection that is 5 to 10 ft (1525 to 3050 mm) above the plant floor, and discharges bulk material dust-free through a slide gate valve.

Transferring Multiple Bulk Materials Without Cross Contamination
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TIP-TITE® Sanitary Drum Dumper with explosion-proof motor from Flexicon transfers bulk materials from drums to downstream equipment dust-free.

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