Spiroflow Bulk Bag Discharger Described As “Terrific” By Fish Food Manufacturer

With the installation of a Type 5 ‘Spiroflow’ Bulk Bag Discharger, a leading fish food manufacturer in the United Kingdom has cut its production time to five minutes from 25 to 30 minutes in discharging each of the 11 ingredients used in the production of fish feed for its industrial fish farming operation. This is being achieved by using the Type 5 Discharger rather than simply hanging the bags from a forklift truck.

Skretting of Longridge is the largest aquaculture feeds producer in the United Kingdom and leads the market with innovative feeds and feeding expertise. Located in Lancashire, it is part of the Nutreco group of companies, which has operations in 22 countries, including the USA, and employs over 12,000 people. Global turnover for the company is 3.8 million Euros, roughly $5.4 million US dollars.

At their Longridge site, Skretting produces a variety of feed for industrial trout farming as well as some for salmon. The company’s 30 employees produce 24,000 tons of fish food annually or about 100 tons day.

The Type 5 Spiroflow Bulk Bag Discharger supplied to Skretting is specifically designed for applications with restricted headroom. At Skretting, there is a mezzanine floor area directly above the location of the bulk bag discharger, which would make it almost impossible to lift full bags into a standard discharger safely.

“There is no comparison to the previous way we operated,” said Bill Edmondson, Production Manager at Skretting of Longridge. “Our Spiroflow Discharger has enabled us to increase productivity while using the fork lift truck for other duties while the bulk bags are being emptied.”

The materials handling system at Skretting was installed over eight years ago by a specialist contractor who included a ‘simple’ bulk bag unloading arrangement that fed ingredients into a Spiroflow Aero-Mechanical Conveyor. The Aero Mechanical Conveyor lifts the products up to a horizontal screw conveyor onto the floor above. The screw conveyor has 11 outlets, each of which delivers ingredients to its appropriate storage bunkers. From there, weighed measures of the required ingredients are loaded into a mixer and, finally, the mixture is pelleted, packed and ready for dispatch.

It was the ‘simple’ bulk bag unloading arrangement that proved to be the bottleneck in the production process and the cause of constant frustration to the operators. Comprising of just a lidded hopper with a spigot to which the neck of the bulk bag was attached, the ''simple'' bulk bag unloading arrangement required the presence of a fork lift truck for the duration of discharge since there was no other means to support the bag.

In addition, an operator had to be on standby to aid the flow of poor flowing or compacted products. 


Spiroflow Type 5 Discharger Described

The Type 5 Bulk Bag Discharger installed by Skretting of Longridge was integrated into the existing ‘Spiroflow’ Aero-Mechanical Conveyor and horizontal screw conveyor set-up.

The ‘Spiroflow’ Bulk Bag Discharger supplied to Skretting is specifically designed for applications with restricted headroom. At Skretting there is a mezzanine floor area directly above the location of the bulk bag discharger, which makes it almost impossible to lift full bags into a standard discharger in safely. Spiroflow’s model T5 discharger has two sections. The upper section, which holds the bags, is lifted off at its base and lowered to ground level. Here, by way of a lifting frame, full bags can be loaded by fork lift truck whose forks only have to be raised a little higher than the height of the bag and its extended lifting loops. Once the bag is safely in place, the top section is lifted via the fork channels at its base back on to the lower section of the discharger - and locked into place. There is a dust-tight docking seal between the upper and lower sections. An access door in the discharger hopper allows the bag to be untied without emissions or spillage. Once the bag is untied, flow begins and this door is closed. Pneumatically operated bag base massagers have been fitted to the lower half of the discharger at Skretting. They are there to deal with any products that are poor flowing or which have become compacted during transit. It is these base massagers that make it essential that the 2 sections of the discharger are locked together. The model T5 discharger incorporates the same spring loaded side tension arms as all other models in the range. These raise the bulk bag as it empties helping to ensure complete discharge and prevent the neck of the bag sagging into the conveyor below.