Theory bites are a collection of basic hydraulic theory and will touch upon pump design and other areas of pump industry knowledge.
The allowable operating range, or AOR, is the portion of a pump curve determined by the pump manufacturer where the pump can be operated continuously without significantly affecting the performance or life of the pump.
The Allowable Operating Range is determined by the pump manufacturer through engineering analysis, testing, and experience. It is the range of operating conditions that the manufacturer considers to be acceptable. While a pump may be operated intermittently for short periods of time outside of the AOR, the large majority of operation should be maintained within the AOR.
The AOR, in contrast to the POR, is defined by the pump manufacturer and not by a standard specification such as the Hydraulic Institute or API610
Source: EKWESTREL CORP by Randal Ferman and Introduction to Centrifugal Pump Fundamentals.
Read more Theory Bites!