Clever Diaphragm Design Makes Pumping Less Stressful
Codip air-operated pumps are a good example of innovative pump design combined with robust construction using durable materials, which together ensure safe and reliable liquids transfer, even when handling the most aggressive media.
Available through Michael Smith Engineers, Codip pumps incorporate PTFE tubular diaphragms, a unique feature compared to conventional air-operated diaphragm pumps.
A key feature of the Codip pump design is that potential areas of concentrated or localized stress have been eliminated, helping to achieve the important benefits of optimum reliability and minimal maintenance.
The pump is operated by a compressed air supply via an independent automatic air distributor to one side of a flat rubber air diaphragm.
This diaphragm is deflected, resulting in displacement of the inert liquid inside the pump casing. As the inert liquid transmits pressure uniformly to the PTFE diaphragm, without any mechanical stress, extremely long tubular diaphragm life is assured. Also, the pumps are secondary contained because the PTFE diaphragm is surrounded by inert liquid which is sealed in place by the air diaphragm and this guarantees zero leakage, in the unlikely event of diaphragm failure.
The absence of mechanical seals, packing or O rings means that the pumped liquid is effectively sealed from the environment, so it's virtually impossible for the pump to leak any process fluid. As a result many Codip pumps are successfully deployed in handling ultra-pure products in the pharmaceutical and food industry where the prime considerations are no contamination, no contact with the atmosphere and ease of sterilisation with steam.
With small modification the pumps can handle liquids containing solids or particles of up to 7mm diameter, to concentrations of 50%. Also, the pumps are suitable for handling paints, polishes and glues because of the non-stick properties of PTFE.
The range covers flow rates from 0 to 300 lit/min at discharge pressures up to 10 bar. Standard pumps can handle fluids with temperatures up to 90 deg C and high temperature versions are available for liquids up to 180 deg C.
Source: Michael Smith Engineers