Impeller Trim For Pump
Impeller Trim For Pump
Impeller Trim For Pump
This means that the power draw decreases by the third power of the
impeller outer diameter reduction. So a 10% diameter reduction (19%
head reduction) would result in a 27% reduction in the power draw, plus
any reduction from the lower percent flow rate. This is the same impact
as pump speed, which can, however, be varied during operation.
The issue then becomes, how much should the impeller diameter be
trimmed for a given application, for maximum energy savings, without
jeopardizing the pump's ability to meet the maximum system flow
objective. A pump can only have one impeller diameter at a time.
However, a replacement impeller with the necessary reduced diameter
may always be ordered from the pump manufacturer, while the original
impeller is then stored for future use if system friction losses are
ultimately increased over time, or if greater capacities are ever required.
The specific steps that should be followed in determining the proper
impeller trim selection are: