Replacing Metal with Plastics

Material challenges are always interesting and when Viridian Systems approached us to replace a metal component with a plastic injection moulded alternative there were many considerations. Viridian provides environmental solutions for the landfill industry. They are renowned for their range of automatic self-regulating VP pumps which assist in the management of landfill leachate. The company was keen to reduce the part weight, but at the same time, it had to be considered that the pumps are manufactured to tight tolerances, high specifications and technical accuracy. Is it possible to replace metal with plastics?

The Rutland Plastics Design Team recognised that the plastic material would need to be very strong as the pumps are continually under immense stress. Additionally, it would need to be able to withstand high temperatures and because of chemicals encountered in the leachate, be corrosion resistant. After selecting the most suitable material, it became clear that an exact copy of the original metal design would not offer the strength required. Our team worked on a series of modifications to gain greater strength and the final result totally fulfilled the customers’ requirements. Furthermore, the success of this part prompted Viridian to explore the replacement of a further component from the same product. We were able to design a plastic replacement for the float used in the pump, the manufacture of which had previously produced a large amount of scrap. Rutland Plastics created a highly unusual solution for the material to facilitate the perfect density for the part to function efficiently. We were delighted when Viridian reported that the new plastic parts were more than a match on performance and additionally outperformed the originals quite significantly on cost.  This result proves that replacement of metals with plastics can be highly successful.