When exploring and learning about pumping systems, I was amazed at the information available online today in 2021. For a non-engineer, there are numerous sites that provide incredibly easy to read and understand information. The U.S. department of energy has done an excellent job with their tear sheets. I’ve provided the information that they teach, as it’s an incredibly reliable resource:
Most pumps operating today were selected to meet a maximum system demand, or potential future demands. This means that most pumps are oversized, rarely operating at their full design capacity. In addition, pumps are often installed in systems with multiple operating points that coincide with process requirements. A throttling valve is usually employed when the process ﬂow requirement is less than the ﬂow at the pumping system’s natural operating point.