Optimising your productivity
4 April 2018, News release from Middleton Engineering Ltd
Conveyor choices across the waste and recycling sector, according to machinery specialist Middleton Engineering, are frequently poorly specified for the job they are meant to do. Cost cutting in favour of standard solutions might be tempting but costly breakdown and performance issues are all too common. Rethinking conveyor procurement in favour of quality and performance is overdue.
While feed conveyors are ubiquitous across the waste and recycling industry, they are rarely given a great deal of thought especially if the investment has already been made in major plant and machinery. This is hardly surprising given the cost pressures faced by the industry, however the temptation to use standard, off-the-shelf solutions, often inappropriately specified for the rigours of the waste sector, seldom makes financial sense long term, especially once breakdown, maintenance and downtime are accounted for.
Reliability is a key factor for the industry yet poor design and prematurely worn out, or over loaded conveyors continually spilling material, are typical. Belt speed, over-stressed motors, poor synchronisation with other machinery and maintenance issues all play their part. As a consequence some organisations are dealing with almost daily breakdowns.
Matching the conveyor to other processes such as a baling press or sorting station is also crucial with a direct bearing on productivity. The ability to deliver uniform, well compacted bales of paper, card or plastics, for example, will depend in part on whether the feed conveyor is up to the job.
As an engineering solutions company focussed on the waste and recycling sector we recommend beginning with a complete understanding of a customer’s requirements together with a site visit, before the specification, design and fabrication process gets underway. That way solutions that are both robust enough for the environment they are designed to operate in and the weight of the materials to be handled can be designed and implemented.
Understanding current and future material volumes and throughput is crucial and there is a huge range of options to consider. These include slider-bed, steel slat, rubber or steel belt, chain driven, inclined, swan neck, fully enclosed, in-floor or on-floor designs.
Generally a chain conveyor is specified where larger volumes of material are being handled. A slider-bed solution is more appropriate for lighter materials and smaller volumes and will generally cost less as it doesn’t need to be as rugged. Products like RDF which can be much denser in volume than card and plastics require higher specification parts for chains, belts, motors and gearboxes. The corrosive nature of the material can also mean higher wear and maintenance considerations.
Achieving a continuous and even flow of material will also depend on factors like belt width, cleat height, levelling gates, motor sizes and SCADA control systems. And on top of that there are operator safety systems as well as features to improve maintenance and cleaning.
Customer experience covers a range of solutions from one off conveyor solutions to complete MRF installations. This includes a chain conveyor to support increased capacity at Viridor’s Priorswood materials recycling facility in Taunton. A series of feed conveyors as part of a turnkey MRF facility for Merthyr Tydfil County Borough Council. Bespoke conveyors to enhance processing requirements at Biffa Polymers, the world’s first food grade High Density Polyethylene (rHDPE) recycling plant and a new sorting line for Amey’s Gloucester City Council waste and recycling depot, comprising a series of five chain and slider bed conveyors. All of these are bespoke solutions, built to last, often with design features to suit individual customer requirements.
The temptation to fit a low cost standard option might provide initial savings, but it’s unlikely to deliver the overall performance you expect and is more likely to result in frustration and downtime. Bespoke solutions designed and tuned for your specific environment are superior, and in the long run guaranteed to be more cost effective and safer to use.
With the right design, a conveyor feeds material at the optimal rate for your process, and at a volume and speed that matches other machines or processes. Generally control systems and telemetry should link each piece of machinery so that they work smoothly and harmoniously as one. It is important, therefore, that your supplier is equally competent with both the mechanical and software aspects of your chosen solution, and able to provide the service and maintenance you need if something does go wrong.