Information

The Problem

On many design applications the discharge head pressure that the pump is actually subjected to most of the time is far less than the Peak Flow High Head condition that the pump was designed for. The pump is then forced to operate at a condition that it was not designed for which often causes a number of serious problems. The first problem is often motor overloading , overheating or electrical shutoff by the motor overload protectors. This can quickly cause a pump station overflow if not immediately detected. Premature failure of the motor can occur from excessive operation temperatures. The results can be PUMP STATION OVERFLOWS and EXCESSIVE WEAR. The second problem caused by operation of a pump at a head condition that it was not designed for is lack of pump efficiency. This causes the power costs to operate the pump to be higher than needed which results in INEFFICIENT OPERATION. The third problem caused by this low pressure condition is pump cavitation. This is often identified by a rattling noise from inside the pump or a vibration. It also causes air entrainment and vortexing due to excessive flow rates. This can destroy a pump and impeller in less than a year. This causes EXCESSIVE WEAR and INEFFICIENT OPERATION.

The fourth problem caused by this variation in pressures at the pump discharge is lack of pump capacity, which often results in PUMP STATION OVERFLOWS. This typically occurs when a pump is downsized by trimming it's impeller from the design capacity to allow it to operate without cavitating or overloading at the low head conditions that it is most often subjected to. When the Peak Condition occurs, the pump does not have sufficient capacity to prevent a PUMP STATION OVERFLOW.

Flow Control Systems, LLC