Test of giant pumps in real conditions

As a worldwide manufacturer of centrifugal pumps and Iris® control valves, our products are tailor-made according to customer specifications.
A few years ago, we analyzed our customer’s requirements and began further development of our RPP/RPG elbow pumps to optimize them for higher flow rates and lower relative differential heads. We have therefore dimensioned a new 3-blade propeller by increasing the relative radius of the elbow. (Ratio radius: pipe diameter)

Performing water tests on pumps of such dimensions (diameter DN 800 to 1400), which transport a heavy liquid in operation, is a real challenge (example: saturated brine with a specific weight of 1.4 kg/dm3 – a power at the point of service greater than 300 kW – a flow rate above 4m3/s and a height of more than 3 m).

For such tests, we have been collaborating for many years with Cetim in Nantes (Technical Center of Mechanical Industries). Last year, a test was carried out upon an RPP 1105 elbow propeller pump at nominal speed (speed, flow and height) in order to validate the dimensioning and thus proceed to trouble-free commissioning.
The Cetim of Nantes is a neutral and certified organization that can test large-sized pumps with frequency driven motors up to 1 megawatt. The pressure measurements carried out downstream and upstream of the pump at a distance of 1 to 2 diameters as well as the flow and torque measurements according to ISO 9906 class 2, are certified and guaranteed.
The basis of the required performance is the specifications of the customer and an engineering office in the Basque Country. The request was to validate the operation of this propeller pump developed for an ultramodern paper mill plant in Indonesia. The system is designed to optimize the recovery process in the hardwood cellulose conversion industry for textile fibers and fine paper manufacturing, by treating 500 tons per day of precipitator separated ashes with Enhanced Chloride Removal Process (ECRP).
Our standard RPP pumps had previously achieved a maximum efficiency of under 75%. With the introduction of the new impeller and casing, our goal was to improve and approach the point of maximum efficiency in the 80% range. We achieved this maximum efficiency of 80% at the CETIM test bench in Nantes during February 2020. We also met the conditions requested by the customer since the operating point is not necessarily at the point of maximum efficiency.

These various tests allowed us to obtain a characteristic with certified values over a given flow range, in compliance with specifications and tolerances.