MATERIALS HANDLING
Series of pump pairings
doubt that if the current duty pump fails, the standby will work – its functionality is regularly demonstrated at every other changeover. As both pumps run regularly, engineers can gather monitoring data on each and therefore predict failure and maintenance needs if deviation from the norm is identified. For this reason, a 50/50 split in operating has become popular. Looking at the disadvantages of an alternating
method, it’s clear that both can be mitigated by utilising the duty/standby configuration. Although the alternating model offers operational benefits in terms of proven reliability, it’s possible to replicate these advantages with a slight modification to a duty/ standby system – with the implementation of test and monitoring procedures, the duty/standby model can provide all these benefits without the disadvantages associated with frequent start-ups. One argument for alternating pumps is that the
standby is known to be ready to operate. Test starts of standby pumps should therefore be implemented to ensure it is available, with the frequency of such
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‘Changeover of duty pumps can be easily aligned to shift changeovers, while there is no doubt that if the current duty pump fails, the standby will work – its functionality is regularly demonstrated at every other changeover.’
starts determined by the pump and the operating fluid. These test starts can be combined with a full test run to mitigate fears of another failure mode – that the standby pump will not be able to maintain the required flow under the operating pressure. By treating a duty/ standby system as a 90/10 or 80/20 system, rather than the 50/50 alternating method, useful condition monitoring data can be collected to provide the same
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