Engineering for good
Bennett Engineering have successfully designed and supplied a cutting tool to resolve an engineering challenge for Aquabox, the charity that provides safe drinking water and humanitarian aid to people affected by natural disasters, extreme weather and conflicts.
The issues Aquabox were facing
Aquabox provide two solutions, a family filter, capable of filtering water at the rate of one litre per minute, and designed to meet the needs of a typical family group and a community filter – exactly the same technology, but scaled up to process up to six litres per minute, and designed for schools, clinics and community centres.
The magic of the Aquabox filter system is the central core of sub-micron filter membranes which are impenetrable to bacteria and most viruses, and which instantly produce safe, clean water for drinking. The problem is that sometimes the plastic pipe containing the straws has not met the strict tolerances that Aquabox requires.
Dominic Wish, Trustee of Aquabox, approached Bennett Engineering at the East Midlands Chamber’s Manufacturing Event at Loughborough University to see if they could help.
The solution created by Bennett Engineering
The short version is that Bennett Engineering designed and manufactured, with our partner S.T. Engineering in Ilkeston, a pencil sharpener!
There’s more to it than that; designing a cutting tool involved seeing the pipes to understand the dimensions supplied as well as having the tolerances for the filter products Aquabox manufacture. Once the information was collected and a concept created which made sense to Dominic, Craig Harbron (Director and Senior Design Engineer) went on to create a CAD design and manufacturing pack with parts list. S.T. Engineering then made the outer parts of the cutting tool which had smart features like the ability to use in a clamp or on a tabletop. Bennett Engineering purchased some standard parts like the cutting blades and the bolts then assembled the cutting tool (aka pencil sharpener!) at their industrial unit.
The cutting tool is designed to shave off some of the external plastic from the pipe without affecting the internal filter. The clever part of the design is that the pipe can not be shaved too much as the limit has been set against the exact tolerance Aquabox require.
Craig said “Even though this might look simple to design and manufacture a lot of thought has gone into this tool. From the people using it, we knew the volunteer age range to the way the plastic would cut when against the blades were all considered as I put the design together. I am really pleased with the outcome.”
The test results
With the day’s construction in full flow during the hand over, a few pipes that were out of the tolerance specification were identified and the tool was put to work straight away.
It’s a simple action of turning the pipe against the angled cutting blade to shave the pipe to get it perfect. The volunteers on the day found the cutting device easy to use and handle when testing during their tea break.
Richard, a volunteer fitter assembler at Aquabox, commented “The handheld unit is great – it’s safe and easy to use.”
Over the weeks since the team have had the pipe cutting tool it’s been used multiple times with everyone being pleased with the results, which ensures the final filter products are perfect to send out to the areas in need of safe drinking water.
Dominic says “The very slightly out-of-tolerance filter components have caused us significant assembly problems resulting in additional scrap. This simple, but effective, tool allows us to shave a small amount from the outside of the filter membrane component prior to gluing into the assembly. Scrap rates are down, and assembly is much easier – thank you to Bennet Engineering.”
Seleena Creedon (Director) said “It’s been our pleasure to help Aquabox with something that might seem small but is clearly crucial to make sure the final filter product is perfect. Aquabox are doing amazing work, we’re proud to have supported them in this small way to carry on getting their life-saving filters out to people who need them.”
Aquabox can continue to manufacture their fantastic filters that bring safe drinking water to places that are in desperate need of it with a little more confidence that everything fits perfectly and so will work for a family or community for years to come.
