An African mine owner was in a fix because a pump which was critical in terms of the process of filling tankers with an ammonium nitrate emulsion from silos not only had too low a performance level but was also constantly breaking down: the pin joint could not withstand the torque during the system's frequent stops and starts and there was severe bending of the coupling rod.
NETZSCH technicians analysed the causes of the problems with the competitor’s pump and established that the design of the current pump was too short and this led to too great a deflection of the coupling rod. In order to increase the reliability of the filling process, a NEMO® progressing cavity pump with a greater conveying capacity and a joint with wear bushing was installed, along with a frequency inverter, which links the adjustment of the pumping volumes with the needs of the medium, without the pump having to be started and stopped again and again. To meet the customer’s special safety requirements, double-acting mechanical seals with thermosiphon vessels were also fitted into the pump.
It has since become clear that the switch has made it possible to increase both the productivity of the system and the length of the maintenance intervals. At the same time the waiting time for the tankers during filling has also been reduced, as this process can be carried out faster than in the past by the larger pump. Significant cost savings for the operator due to the avoidance of downtime are a particularly positive aspect of this.