Building Adhesives Ltd, manufacturers of ‘BAL’ and ‘Dunlop’ construction adhesives, needed a new production line that would generally meet their production targets through single shift working. The new line was designed to replace 3 aging lines that all had to work through a double shift to keep up with demand.

As part of the new production line, two dedicated conveyors were required to transfer the two minor additives from their respective sack-tip stations to weigh hoppers above the main mixer. The conveyors needed to fit into the tight space available and work reliably day in day out.

When asked why they chose to use flexible screw conveyors, Project Engineer, Dave Smith, advised that he knew of their space saving, flexible routing capabilities and their reliability from previous experience elsewhere, “Given that we were tight for space and reliability was a key issue, they were the obvious choice.”

Asked why he chose a ‘Spiroflow’ conveyor rather than a competitor’s; he confirms, “Because your representative took samples of product away for tests and came back with a good offer that included a performance guarantee”.

The 2 conveyors deliver minor additives from sack tip stations to weigh hoppers above a mixing station. Each conveyor is fed from 25kg bags that are slit open on a grill above a buffer hopper. Several sacks are tipped at a time into the buffer hoppers, which sit above the conveyor inlets. The buffer hoppers are furnished with dust containment cabinets that are connected to the factory’s central dust extraction system.

The ‘Spiroflow’ conveyors operate in response to a signal at the start of each new batch of product. They run until the respective load cell mounted minor-additive weigh hoppers, that they serve, reach their target weights.

Given that the conveyors are dedicated to their individual products, they do not have to be cleaned between batches. They have been in operation since they were installed in November 2004 without requiring any attention. As Engineering Co-ordinator, Kevin Beech confirms, “They have been very reliable”.