Information on the pump test bench in general:

With the help of a throttle on the suction side, it is NOT possible to measure according to standards. The following explanation: A throttle characteristic is always related to a pump speed, i.e. a change in speed causes a shift in the throttle characteristic.

A throttle device (gate valve) creates an additional pressure loss, which causes a loss of specific pumping energy and thus a steeper system characteristic curve.

This shift cannot be recorded with suction-side throttling because these preset throttling losses are not constant, they change depending on the flow rate and add up with the friction losses to a total loss (pe) for which the size of the individual sums is not known. Due to the throttling of the suction cross-section, the pump characteristic curve cannot be completely absorbed, the system characteristic curve shifts and cavitation is favoured. The reproducibility of measured values will hardly be possible. This method can in no way be seen as an alternative to systems with suction shafts or vacuum tanks and is therefore not offered. In addition, there is an increased risk of cavitation!

However, it is possible to convert existing plants. This will usually be much cheaper than a new plant.

We will be happy to advise you specifically on your system or local conditions.