Flexible screw conveyor and bulk bag discharger feeds flour directly into a mixer at United Biscuits.


In 1851, brothers William and Robert Jacobs founded W & R Jacob’s Ltd. The first ‘Cream Cookie’ was produced in 1885 and the first now famous Club brand cream chocolate-coated cookie in 1919.  In 2004, United Kingdom-based United Biscuits (UB) purchased Jacob’s, including its brands Club, Iced Gems, Fig Rolls, Cheddars and Twiglets, which combined with United Brand’s existing brands such as Carr’s, makes it the UK’s No. 1 cookie producer.

The Jacob’s Bakeries plant of United Brands is situated on 50 acres at Aintree near Liverpool with more than 800 employees. Current production output is 50,000 tons of cookies a year.

For 14 trouble-free years, Jacob’s Bakeries has been using a Type 6 bulk bag discharger (BBD) from Spiroflow Ltd. with an integral flexible screw conveyor (FSC). Spiroflow’s partner company for North and South America, Spiroflow Systems, Inc., is located in Monroe, N.C. The Type 6 BBD has an integral hoist that enables delivery of the 2,200 lb. bulk bags to the discharger by an electrically powered pallet truck. Since the Bulk Bag Discharger is on an upper floor, a passenger/freight elevator is used to transport the bulk bags and the pallet truck from the ground level. Transfer from the BBD to the mixer is through the Flexible Screw Conveyor, which loads brown oat flour into the mixer through a storage silo.

The Type 6 BBD with optional 304 stainless steel contact parts was tailored to suit the exact specifications of Jacob’s Bakeries. The unit has a 1-ton hoist controlled by one operator that positions the bulk bag into the discharger. The hoist runs along a fully load tested integral “I” lifting beam. 

To compensate for the capacity/weight of the bag, innovative bag tensioning supports stretch it to ensure total discharge. Each discharger has a dust tight material collection hopper with an integral locking access door and viewing port. The door is amply sized to enable the operator to untie/re-tie the bag spout and liner.

In order to produce other products in the same mixer, Jacob’s needed a way to by-pass the storage silo and load alternative flours directly into the mixer. To achieve this, Jacob’s installed a second Spiroflow FSC directly adjacent to the existing Type 6 Spiroflow BBD, which went into operation June 2009.

The second FSC directly feeds bags of brown flour through an existing bag dump hopper into the mixer that produces the base of Jacob’s world famous Club brand sandwich-layered cookies, Gold brand cookies and some cookies for the company’s Cheese brand label.

Operating 14 hours a day, seven days a week, the mixer now produces a new batch of cookie dough every 30 minutes. That’s a challenge for the two Spiroflow FSC’s since they have to continuously keep the mixer fed.

The newly installed FSC is 36 ft. long and is used to lift the brown flour 16 ft. at approximately a 45o angle. An agitator prevents any bridging of the coarse blown flour above the inlet of the FSC.   A magnet also is supplied to prevent tramp metal from getting into the mixer. Both the conveyor and controls are designed to operate in a European CE ATEX Zone 22 Equipment Directorate for hazardous areas.

Nine different models of FSC’s from Spiroflow are available with throughputs from 10 to 88,000 lb. per hour depending on the material being conveyed and the angle of operation.

The new FSC at Jacob’s Bakeries has a simplified direct electric motor-driven spiral screw that rotates the conveyor at high speeds. With few parts to wear, the Spiroflow FSC is lower in cost since there are no unnecessary components resulting in a more sanitary modular design for greater flexibility.

In addition, maintenance is simple since the only moving part is the spiral screw that rotates material within a sealed tube and moves it along by its revolutionary homogenizing conveying action.

With its sanitary design, the FSC meets most hygienic conveying needs since spiral screws that are available in ultra-high grade and heat-tempered stainless steel or heat-treated spring steel for longer life.

Three types of spiral screws are available: a standard round screw that handles most applications, a flat screw for certain light or aerated products and a beveled screw for conveying difficult materials such as iron oxide or products that smear such as chocolate.

About Spiroflow Systems
Spiroflow is a worldwide supplier of a wide range of both standard and custom powder handling equipment, specializing in mechanical and pneumatic conveyors, bulk bag dischargers and fillers, a range of 50-lb. bag packing and unloading equipment and flexible storage silos. The company offers a wide range of innovative designs and design options.

Spiroflow Systems recently purchased Dynamet Systems of Kalamazoo, Mich., a leading supplier of tubular drag chain conveyors and flexible screw conveyors.

For more information, visit www.spiroflowsystems.com, call 704-291-9595 or email info@spiroflowsystems.com.