To receive the weekly EBS newsletter
      Home            News          Advertising       Events         About us      Archive Issues     In-House Test Centres   
08.06.2020 Screw feeder ensures even flow of carbon black

Ajax Equipment, Bolton, UK, has supplied a leading custom heat transfer solution manufacturer with a horizontal screw feeder to handle carbon black powder. The stainless steel single screw feeder ensures carbon black is evenly extracted across the inlet from the hopper above, resulting in uniform flow. The manufacturer’s existing equipment provided mass flow – sufficient in most processes – but in this application any variance in residence time and therefore powder temperature could have undesirable effects.

The screw feeder transfers carbon black powder, a challenging material to handle, as part of a cooling process. Ajax managing director Eddie McGee commented: “The customer required good flow from a material that needs considered design. Ajax developed a feeder that provides the most even hopper residence time possible through progressive extraction geometry and a gentle extraction pattern.” He went on: “A further requirement was for the machine to have a maintenance friendly construction. In response Ajax designed the feeder with a profiled clean-out door under the inlet, allowing easy access to the screw.”

He explained that in most applications mass flow, where all material moves together, provides a reliable supply of material in the condition required for further processing. However, although all the material moves, it does not flow entirely evenly. Uniform flow moves completely evenly.

In the case of process applications, such as heating or cooling, the differing rates at which regions of material pass through a hopper can result in undesired differences in material condition, in this case temperature. Uniform flow offers even drawdown and equal residence time, ensuring that all of the material has the same opportunity to settle, resulting in a consistent condition. However, uniform flow is not easy to achieve and requires very careful design of the hopper and equipment to extract the contents.

The Ajax horizontal single screw feeder uniformly transfers carbon black powder

« Back